Re: [Fwd: Re: proposal: new long psql parameter --on-error-stop]

commit 4d8a267870f15a22818da226f72223db86944636
Author: Pavel Stehule <pavel.stehule@gooddata.com>
Date:   Mon Jun 23 19:38:41 2014 +0200

    without comments

diff --git a/src/bin/psql/help.c b/src/bin/psql/help.c
index 3aa3c16..e960f34 100644
--- a/src/bin/psql/help.c
+++ b/src/bin/psql/help.c
@@ -78,12 +78,13 @@ usage(void)
 	printf(_("  -f, --file=FILENAME      execute commands from file, then exit\n"));
 	printf(_("  -l, --list               list available databases, then exit\n"));
 	printf(_("  -v, --set=, --variable=NAME=VALUE\n"
-			 "                           set psql variable NAME to VALUE\n"));
+			 "                           set psql variable NAME to VALUE e.g.: -v ON_ERROR_STOP=1\n"));
 	printf(_("  -V, --version            output version information, then exit\n"));
 	printf(_("  -X, --no-psqlrc          do not read startup file (~/.psqlrc)\n"));
 	printf(_("  -1 (\"one\"), --single-transaction\n"
 			 "                           execute as a single transaction (if non-interactive)\n"));
 	printf(_("  -?, --help               show this help, then exit\n"));
+	printf(_("  --help-variables         list of available configuration variables (options), then exit\n"));
 
 	printf(_("\nInput and output options:\n"));
 	printf(_("  -a, --echo-all           echo all input from script\n"));
@@ -279,6 +280,84 @@ slashUsage(unsigned short int pager)
 }
 
 
+/*
+ * show list of available variables (options) from command line
+ */
+void
+help_variables(void)
+{
+	printf(_("List of variables (options) for use from command line.\n"));
+
+	printf(_("psql variables:\n"));
+	printf(_("Usage:\n"));
+	printf(_("  psql --set=NAME=VALUE\n  or \\set NAME VALUE in interactive mode\n\n"));
+
+	printf(_("  AUTOCOMMIT         successful SQL commands are automatically committed\n"));
+	printf(_("  COMP_KEYWORD_CASE  determines which letter case to use when completing an SQL key word\n"));
+	printf(_("  DBNAME             name of currently connected database\n"));
+	printf(_("  ECHO               controls what input can be writtent to standard output [all, queries]\n"));
+	printf(_("  ECHO_HIDDEN        display internal queries (same as -E option)\n"));
+	printf(_("  ENCODING           current client character set encoding\n"));
+	printf(_("  FETCH_COUNT        fetch many rows at a time (use less memory) (default 0 unlimited)\n"));
+	printf(_("  HISTCONTROL        when set, controls history list [ignorespace, ignoredups, ignoreboth]\n"));
+	printf(_("  HISTFILE           file name used to store the history list\n"));
+	printf(_("  HISTSIZE           the number of commands to store in the command history\n"));
+	printf(_("  HOST               the currently connected database server\n"));
+	printf(_("  IGNOREEOF          if unset, sending an EOF to interactive session terminates application\n"));
+	printf(_("  LASTOID            the value of last affected OID\n"));
+	printf(_("  ON_ERROR_ROLLBACK  when on, the error doesn't break transaction (due implicit SAVEPOINs)\n"));
+	printf(_("  ON_ERROR_STOP      stop batch execution after error\n"));
+	printf(_("  PORT               the database server port\n"));
+	printf(_("  PROMPT1, PROMPT2, PROMPT3\n"
+					 "                     specify the psql prompt\n"));
+	printf(_("  QUIET              run quietly (same as -q option)\n"));
+	printf(_("  SINGLELINE         end of line terminates SQL command mode (same as -S option)\n"));
+	printf(_("  SINGLESTEP         confirm each query mode (same as -s option)\n"));
+	printf(_("  USER               the database user currently connected\n"));
+	printf(_("  VERBOSITY          control verbosity of error reports [default, verbose, terse]\n"));
+
+	printf(_("\nPrinting options:\n"));
+	printf(_("Usage:\n"));
+	printf(_("  psql --pset=NAME[=VALUE]\n  or \\pset NAME [VALUE] in interactive mode\n\n"));
+
+	printf(_("  border             border style (number)\n"));
+	printf(_("  fieldsep           field separator for unaligned output (default '|')\n"));
+	printf(_("  fieldsep_zero      set field separator in unaligned mode to zero\n"));
+	printf(_("  format             set output format [unaligned, aligned, wrapped, html, latex, ..]\n"));
+	printf(_("  linestyle          sets the border line drawing style [ascii, old-ascii, unicode]\n"));
+	printf(_("  null               sets the string to be printed in place of a null value\n"));
+	printf(_("  pager              when the pager option is off, the pager program is not used\n"));
+	printf(_("  recordsep          specifies the record (line) separator to use in unaligned output format\n"));
+	printf(_("  recordsep_zero     record separator be in unaligned output format a zero byte\n"));
+	printf(_("  title              sets the table title for any subsequently printed tables\n"));
+	printf(_("  tuples_only        in tuples-only mode, only actual table data is shown\n"));
+
+	printf(_("\nEnvironment options:\n"));
+	printf(_("Usage:\n"));
+	printf(_("  NAME=VALUE [NAME=VALUE] psql ...\n  or \\setenv NAME [VALUE] in interactive mode\n\n"));
+
+	printf(_("  COLUMNS            number of columns for wrapped format\n"));
+	printf(_("  PAGER              used pager\n"));
+	printf(_("  PGDATABASE         same as the dbname connection parameter\n"));
+	printf(_("  PGHOST             same as the host connection parameter\n"));
+	printf(_("  PGPORT             same as the port connection parameter\n"));
+	printf(_("  PGUSER             same as the user connection parameter\n"));
+	printf(_("  PGPASSWORD         possibility to set password (not recommended)\n"));
+	printf(_("  PGPASSFILE         password file (default ~/.pgpass)\n"));
+	printf(_("  PSQL_EDITOR, EDITOR, VISUAL\n"
+					 "                     editor used by \\e \\ef commands\n"));
+	printf(_("  PSQL_EDITOR_LINE_NUMBER_ARG\n"
+					 "                     style how line number is used in editor\n"));
+	printf(_("  PSQL_HISTORY       alternative location for the command history file\n"));
+	printf(_("  PSQLRC             alternative location of the user's .psqlrc file\n"));
+	printf(_("  SHELL              command executed by the \\! command\n"));
+	printf(_("  TMPDIR             directory for storing temporary files\n"));
+
+	printf(_("\nFor more information consult the psql section in the PostgreSQL\n"
+			 "documentation.\n\n"));
+	printf(_("Report bugs to <pgsql-bugs@postgresql.org>.\n"));
+}
+
 
 /*
  * helpSQL -- help with SQL commands
diff --git a/src/bin/psql/help.h b/src/bin/psql/help.h
index 054d5a4..e7affff 100644
--- a/src/bin/psql/help.h
+++ b/src/bin/psql/help.h
@@ -12,6 +12,8 @@ void		usage(void);
 
 void		slashUsage(unsigned short int pager);
 
+void		help_variables(void);
+
 void		helpSQL(const char *topic, unsigned short int pager);
 
 void		print_copyright(void);
diff --git a/src/bin/psql/startup.c b/src/bin/psql/startup.c
index 45653a1..d911159 100644
--- a/src/bin/psql/startup.c
+++ b/src/bin/psql/startup.c
@@ -383,6 +383,7 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 		{"expanded", no_argument, NULL, 'x'},
 		{"no-psqlrc", no_argument, NULL, 'X'},
 		{"help", no_argument, NULL, '?'},
+		{"help-variables", no_argument, NULL, 1},
 		{NULL, 0, NULL, 0}
 	};
 
@@ -566,6 +567,9 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 					exit(EXIT_FAILURE);
 				}
 				break;
+			case 1:
+				help_variables();
+				exit(EXIT_SUCCESS);
 			default:
 				fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
 						pset.progname);

commit 4d77ccf19ac77dc0f43a58f4d2b74d4aebed871d
Author: Pavel Stehule <pavel.stehule@gooddata.com>
Date:   Mon Jun 23 19:38:41 2014 +0200

    without comments

diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml
index ee6ec3a..6a172dc 100644
--- a/doc/src/sgml/ref/psql-ref.sgml
+++ b/doc/src/sgml/ref/psql-ref.sgml
@@ -556,6 +556,15 @@ EOF
       </listitem>
     </varlistentry>
 
+    <varlistentry>
+      <term><option>--help-variables</></term>
+      <listitem>
+      <para>
+      Show help about <application>psql</application> variables,
+      and exit.
+      </para>
+      </listitem>
+    </varlistentry>
   </variablelist>
  </refsect1>
 
diff --git a/src/bin/psql/help.c b/src/bin/psql/help.c
index 3aa3c16..1304e1a 100644
--- a/src/bin/psql/help.c
+++ b/src/bin/psql/help.c
@@ -78,12 +78,13 @@ usage(void)
 	printf(_("  -f, --file=FILENAME      execute commands from file, then exit\n"));
 	printf(_("  -l, --list               list available databases, then exit\n"));
 	printf(_("  -v, --set=, --variable=NAME=VALUE\n"
-			 "                           set psql variable NAME to VALUE\n"));
+			 "                           set psql variable NAME to VALUE e.g.: -v ON_ERROR_STOP=1\n"));
 	printf(_("  -V, --version            output version information, then exit\n"));
 	printf(_("  -X, --no-psqlrc          do not read startup file (~/.psqlrc)\n"));
 	printf(_("  -1 (\"one\"), --single-transaction\n"
 			 "                           execute as a single transaction (if non-interactive)\n"));
 	printf(_("  -?, --help               show this help, then exit\n"));
+	printf(_("  --help-variables         show a list of all specially treated variables, then exit\n"));
 
 	printf(_("\nInput and output options:\n"));
 	printf(_("  -a, --echo-all           echo all input from script\n"));
@@ -279,6 +280,92 @@ slashUsage(unsigned short int pager)
 }
 
 
+/*
+ * show list of available variables (options) from command line
+ */
+void
+help_variables(void)
+{
+	printf(_("List of specially treated variables.\n"));
+
+	printf(_("psql variables:\n"));
+	printf(_("Usage:\n"));
+	printf(_("  psql --set=NAME=VALUE\n  or \\set NAME VALUE in interactive mode\n\n"));
+
+	printf(_("  AUTOCOMMIT         successful SQL commands are automatically committed\n"));
+	printf(_("  COMP_KEYWORD_CASE  determines which letter case to use when completing an SQL key word\n"));
+	printf(_("  DBNAME             name of currently connected database\n"));
+	printf(_("  ECHO               control what input can be written to standard output [all, queries]\n"));
+	printf(_("  ECHO_HIDDEN        display internal queries executed by backslash commands\n"));
+	printf(_("  ENCODING           current client character set encoding\n"));
+	printf(_("  FETCH_COUNT        the number of result rows to fetch and display at a time\n"
+					 "                     (default: 0=unlimited)\n"));
+	printf(_("  HISTCONTROL        control history list [ignorespace, ignoredups, ignoreboth]\n"));
+	printf(_("  HISTFILE           file name used to store the history list\n"));
+	printf(_("  HISTSIZE           the number of commands to store in the command history\n"));
+	printf(_("  HOST               the currently connected database server\n"));
+	printf(_("  IGNOREEOF          if unset, sending an EOF to interactive session terminates application\n"));
+	printf(_("  LASTOID            the value of last affected OID\n"));
+	printf(_("  ON_ERROR_ROLLBACK  when on, the error doesn't break transaction (due implicit SAVEPOINs)\n"));
+	printf(_("  ON_ERROR_STOP      stop batch execution after error\n"));
+	printf(_("  PORT               the database server port\n"));
+	printf(_("  PROMPT1, PROMPT2, PROMPT3\n"
+					 "                     specify the psql prompt\n"));
+	printf(_("  QUIET              run quietly (same as -q option)\n"));
+	printf(_("  SINGLELINE         end of line terminates SQL command mode (same as -S option)\n"));
+	printf(_("  SINGLESTEP         confirm each query mode (same as -s option)\n"));
+	printf(_("  USER               the database user currently connected as\n"));
+	printf(_("  VERBOSITY          control verbosity of error reports [default, verbose, terse]\n"));
+
+	printf(_("\nPrinting options:\n"));
+	printf(_("Usage:\n"));
+	printf(_("  psql --pset=NAME[=VALUE]\n  or \\pset NAME [VALUE] in interactive mode\n\n"));
+
+	printf(_("  border             border style (number)\n"));
+	printf(_("  columns            sets the target width for the wrapped format\n"));
+	printf(_("  expanded (or x)    toggle expanded output\n"));
+	printf(_("  fieldsep           field separator for unaligned output (default '|')\n"));
+	printf(_("  fieldsep_zero      set field separator in unaligned mode to zero\n"));
+	printf(_("  format             set output format [unaligned, aligned, wrapped, html, latex, ..]\n"));
+	printf(_("  footer             enable or disable display of the table foote [on, off]\n"));
+	printf(_("  linestyle          sets the border line drawing style [ascii, old-ascii, unicode]\n"));
+	printf(_("  null               sets the string to be printed in place of a null value\n"));
+	printf(_("  numericlocale      enable or disable display of a locale-specific character to separate\n"
+					 "                     groups digits [on, off]\n"));
+	printf(_("  pager              when the pager option is off, the pager program is not used\n"));
+	printf(_("  recordsep          specifies the record (line) separator to use in unaligned output format\n"));
+	printf(_("  recordsep_zero     record separator be in unaligned output format a zero byte\n"));
+	printf(_("  tableattr (or T)   specifies attributies for table tag in html format or proportional\n"
+					 "                     column width of left aligned data type in latex format\n"));
+	printf(_("  title              sets the table title for any subsequently printed tables\n"));
+	printf(_("  tuples_only        in tuples-only mode, only actual table data is shown\n"));
+
+	printf(_("\nEnvironment variables:\n"));
+	printf(_("Usage:\n"));
+	printf(_("  NAME=VALUE [NAME=VALUE] psql ...\n  or \\setenv NAME [VALUE] in interactive mode\n\n"));
+
+	printf(_("  COLUMNS            number of columns for wrapped format\n"));
+	printf(_("  PAGER              used pager\n"));
+	printf(_("  PGDATABASE         same as the dbname connection parameter\n"));
+	printf(_("  PGHOST             same as the host connection parameter\n"));
+	printf(_("  PGPORT             same as the port connection parameter\n"));
+	printf(_("  PGUSER             same as the user connection parameter\n"));
+	printf(_("  PGPASSWORD         possibility to set password (not recommended)\n"));
+	printf(_("  PGPASSFILE         password file (default ~/.pgpass)\n"));
+	printf(_("  PSQL_EDITOR, EDITOR, VISUAL\n"
+					 "                     editor used by \\e \\ef commands\n"));
+	printf(_("  PSQL_EDITOR_LINE_NUMBER_ARG\n"
+					 "                     style how line number is used in editor\n"));
+	printf(_("  PSQL_HISTORY       alternative location for the command history file\n"));
+	printf(_("  PSQLRC             alternative location of the user's .psqlrc file\n"));
+	printf(_("  SHELL              command executed by the \\! command\n"));
+	printf(_("  TMPDIR             directory for storing temporary files\n"));
+
+	printf(_("\nFor more information consult the psql section in the PostgreSQL\n"
+			 "documentation.\n\n"));
+	printf(_("Report bugs to <pgsql-bugs@postgresql.org>.\n"));
+}
+
 
 /*
  * helpSQL -- help with SQL commands
diff --git a/src/bin/psql/help.h b/src/bin/psql/help.h
index 054d5a4..e7affff 100644
--- a/src/bin/psql/help.h
+++ b/src/bin/psql/help.h
@@ -12,6 +12,8 @@ void		usage(void);
 
 void		slashUsage(unsigned short int pager);
 
+void		help_variables(void);
+
 void		helpSQL(const char *topic, unsigned short int pager);
 
 void		print_copyright(void);
diff --git a/src/bin/psql/startup.c b/src/bin/psql/startup.c
index 45653a1..d911159 100644
--- a/src/bin/psql/startup.c
+++ b/src/bin/psql/startup.c
@@ -383,6 +383,7 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 		{"expanded", no_argument, NULL, 'x'},
 		{"no-psqlrc", no_argument, NULL, 'X'},
 		{"help", no_argument, NULL, '?'},
+		{"help-variables", no_argument, NULL, 1},
 		{NULL, 0, NULL, 0}
 	};
 
@@ -566,6 +567,9 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 					exit(EXIT_FAILURE);
 				}
 				break;
+			case 1:
+				help_variables();
+				exit(EXIT_SUCCESS);
 			default:
 				fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
 						pset.progname);

commit 4d77ccf19ac77dc0f43a58f4d2b74d4aebed871d
Author: Pavel Stehule <pavel.stehule@gooddata.com>
Date:   Mon Jun 23 19:38:41 2014 +0200

    without comments

diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml
index ee6ec3a..6a172dc 100644
--- a/doc/src/sgml/ref/psql-ref.sgml
+++ b/doc/src/sgml/ref/psql-ref.sgml
@@ -556,6 +556,15 @@ EOF
       </listitem>
     </varlistentry>
 
+    <varlistentry>
+      <term><option>--help-variables</></term>
+      <listitem>
+      <para>
+      Show help about <application>psql</application> variables,
+      and exit.
+      </para>
+      </listitem>
+    </varlistentry>
   </variablelist>
  </refsect1>
 
diff --git a/src/bin/psql/help.c b/src/bin/psql/help.c
index 3aa3c16..1304e1a 100644
--- a/src/bin/psql/help.c
+++ b/src/bin/psql/help.c
@@ -78,12 +78,13 @@ usage(void)
 	printf(_("  -f, --file=FILENAME      execute commands from file, then exit\n"));
 	printf(_("  -l, --list               list available databases, then exit\n"));
 	printf(_("  -v, --set=, --variable=NAME=VALUE\n"
-			 "                           set psql variable NAME to VALUE\n"));
+			 "                           set psql variable NAME to VALUE e.g.: -v ON_ERROR_STOP=1\n"));
 	printf(_("  -V, --version            output version information, then exit\n"));
 	printf(_("  -X, --no-psqlrc          do not read startup file (~/.psqlrc)\n"));
 	printf(_("  -1 (\"one\"), --single-transaction\n"
 			 "                           execute as a single transaction (if non-interactive)\n"));
 	printf(_("  -?, --help               show this help, then exit\n"));
+	printf(_("  --help-variables         show a list of all specially treated variables, then exit\n"));
 
 	printf(_("\nInput and output options:\n"));
 	printf(_("  -a, --echo-all           echo all input from script\n"));
@@ -279,6 +280,92 @@ slashUsage(unsigned short int pager)
 }
 
 
+/*
+ * show list of available variables (options) from command line
+ */
+void
+help_variables(void)
+{
+	printf(_("List of specially treated variables.\n"));
+
+	printf(_("psql variables:\n"));
+	printf(_("Usage:\n"));
+	printf(_("  psql --set=NAME=VALUE\n  or \\set NAME VALUE in interactive mode\n\n"));
+
+	printf(_("  AUTOCOMMIT         successful SQL commands are automatically committed\n"));
+	printf(_("  COMP_KEYWORD_CASE  determines which letter case to use when completing an SQL key word\n"));
+	printf(_("  DBNAME             name of currently connected database\n"));
+	printf(_("  ECHO               control what input can be written to standard output [all, queries]\n"));
+	printf(_("  ECHO_HIDDEN        display internal queries executed by backslash commands\n"));
+	printf(_("  ENCODING           current client character set encoding\n"));
+	printf(_("  FETCH_COUNT        the number of result rows to fetch and display at a time\n"
+					 "                     (default: 0=unlimited)\n"));
+	printf(_("  HISTCONTROL        control history list [ignorespace, ignoredups, ignoreboth]\n"));
+	printf(_("  HISTFILE           file name used to store the history list\n"));
+	printf(_("  HISTSIZE           the number of commands to store in the command history\n"));
+	printf(_("  HOST               the currently connected database server\n"));
+	printf(_("  IGNOREEOF          if unset, sending an EOF to interactive session terminates application\n"));
+	printf(_("  LASTOID            the value of last affected OID\n"));
+	printf(_("  ON_ERROR_ROLLBACK  when on, the error doesn't stop transaction (uses implicit SAVEPOINTs)\n"));
+	printf(_("  ON_ERROR_STOP      stop batch execution after error\n"));
+	printf(_("  PORT               server port of the current connection\n"));
+	printf(_("  PROMPT1, PROMPT2, PROMPT3\n"
+					 "                     specify the psql prompt\n"));
+	printf(_("  QUIET              run quietly (same as -q option)\n"));
+	printf(_("  SINGLELINE         end of line terminates SQL command mode (same as -S option)\n"));
+	printf(_("  SINGLESTEP         single-step mode (same as -s option)\n"));
+	printf(_("  USER               the database user currently connected as\n"));
+	printf(_("  VERBOSITY          control verbosity of error reports [default, verbose, terse]\n"));
+
+	printf(_("\nPrinting options:\n"));
+	printf(_("Usage:\n"));
+	printf(_("  psql --pset=NAME[=VALUE]\n  or \\pset NAME [VALUE] in interactive mode\n\n"));
+
+	printf(_("  border             border style (number)\n"));
+	printf(_("  columns            set the target width for the wrapped format\n"));
+	printf(_("  expanded (or x)    toggle expanded output\n"));
+	printf(_("  fieldsep           field separator for unaligned output (default '|')\n"));
+	printf(_("  fieldsep_zero      set field separator in unaligned mode to zero\n"));
+	printf(_("  format             set output format [unaligned, aligned, wrapped, html, latex, ..]\n"));
+	printf(_("  footer             enable or disable display of the table foote [on, off]\n"));
+	printf(_("  linestyle          set the border line drawing style [ascii, old-ascii, unicode]\n"));
+	printf(_("  null               set the string to be printed in place of a null value\n"));
+	printf(_("  numericlocale      enable or disable display of a locale-specific character to separate\n"
+					 "                     groups digits [on, off]\n"));
+	printf(_("  pager              control the use of pager program of query and help output\n"));
+	printf(_("  recordsep          specify the record (line) separator to use in unaligned output format\n"));
+	printf(_("  recordsep_zero     set the record separator to use in unaligned output format to a zero byte.\n"));
+	printf(_("  tableattr (or T)   specify attributies for table tag in html format or proportional\n"
+					 "                     column width of left aligned data type in latex format\n"));
+	printf(_("  title              set the table title for any subsequently printed tables\n"));
+	printf(_("  tuples_only        when on, only actual table data is shown\n"));
+
+	printf(_("\nEnvironment variables:\n"));
+	printf(_("Usage:\n"));
+	printf(_("  NAME=VALUE [NAME=VALUE] psql ...\n  or \\setenv NAME [VALUE] in interactive mode\n\n"));
+
+	printf(_("  COLUMNS            number of columns for wrapped format\n"));
+	printf(_("  PAGER              used pager\n"));
+	printf(_("  PGDATABASE         same as the dbname connection parameter\n"));
+	printf(_("  PGHOST             same as the host connection parameter\n"));
+	printf(_("  PGPORT             same as the port connection parameter\n"));
+	printf(_("  PGUSER             same as the user connection parameter\n"));
+	printf(_("  PGPASSWORD         connection password (not recommended)\n"));
+	printf(_("  PGPASSFILE         password file name\n"));
+	printf(_("  PSQL_EDITOR, EDITOR, VISUAL\n"
+					 "                     editor used by \\e \\ef commands\n"));
+	printf(_("  PSQL_EDITOR_LINE_NUMBER_ARG\n"
+					 "                     style how line number is used in editor\n"));
+	printf(_("  PSQL_HISTORY       alternative location for the command history file\n"));
+	printf(_("  PSQLRC             alternative location of the user's .psqlrc file\n"));
+	printf(_("  SHELL              command executed by the \\! command\n"));
+	printf(_("  TMPDIR             directory for storing temporary files\n"));
+
+	printf(_("\nFor more information consult the psql section in the PostgreSQL\n"
+			 "documentation.\n\n"));
+	printf(_("Report bugs to <pgsql-bugs@postgresql.org>.\n"));
+}
+
 
 /*
  * helpSQL -- help with SQL commands
diff --git a/src/bin/psql/help.h b/src/bin/psql/help.h
index 054d5a4..e7affff 100644
--- a/src/bin/psql/help.h
+++ b/src/bin/psql/help.h
@@ -12,6 +12,8 @@ void		usage(void);
 
 void		slashUsage(unsigned short int pager);
 
+void		help_variables(void);
+
 void		helpSQL(const char *topic, unsigned short int pager);
 
 void		print_copyright(void);
diff --git a/src/bin/psql/startup.c b/src/bin/psql/startup.c
index 45653a1..d911159 100644
--- a/src/bin/psql/startup.c
+++ b/src/bin/psql/startup.c
@@ -383,6 +383,7 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 		{"expanded", no_argument, NULL, 'x'},
 		{"no-psqlrc", no_argument, NULL, 'X'},
 		{"help", no_argument, NULL, '?'},
+		{"help-variables", no_argument, NULL, 1},
 		{NULL, 0, NULL, 0}
 	};
 
@@ -566,6 +567,9 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 					exit(EXIT_FAILURE);
 				}
 				break;
+			case 1:
+				help_variables();
+				exit(EXIT_SUCCESS);
 			default:
 				fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
 						pset.progname);

commit 44ba9d7fc1816dde4605ef59ea68b92b8ceb1c57
Author: Pavel Stehule <pavel.stehule@gooddata.com>
Date:   Sat Jun 28 14:19:47 2014 +0200

    initial

diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml
index ee6ec3a..6a172dc 100644
--- a/doc/src/sgml/ref/psql-ref.sgml
+++ b/doc/src/sgml/ref/psql-ref.sgml
@@ -556,6 +556,15 @@ EOF
       </listitem>
     </varlistentry>
 
+    <varlistentry>
+      <term><option>--help-variables</></term>
+      <listitem>
+      <para>
+      Show help about <application>psql</application> variables,
+      and exit.
+      </para>
+      </listitem>
+    </varlistentry>
   </variablelist>
  </refsect1>
 
diff --git a/src/bin/psql/help.c b/src/bin/psql/help.c
index 3aa3c16..d7da7c3 100644
--- a/src/bin/psql/help.c
+++ b/src/bin/psql/help.c
@@ -78,12 +78,13 @@ usage(void)
 	printf(_("  -f, --file=FILENAME      execute commands from file, then exit\n"));
 	printf(_("  -l, --list               list available databases, then exit\n"));
 	printf(_("  -v, --set=, --variable=NAME=VALUE\n"
-			 "                           set psql variable NAME to VALUE\n"));
+			 "                           set psql variable NAME to VALUE e.g.: -v ON_ERROR_STOP=1\n"));
 	printf(_("  -V, --version            output version information, then exit\n"));
 	printf(_("  -X, --no-psqlrc          do not read startup file (~/.psqlrc)\n"));
 	printf(_("  -1 (\"one\"), --single-transaction\n"
 			 "                           execute as a single transaction (if non-interactive)\n"));
 	printf(_("  -?, --help               show this help, then exit\n"));
+	printf(_("  --help-variables         show a list of all specially treated variables, then exit\n"));
 
 	printf(_("\nInput and output options:\n"));
 	printf(_("  -a, --echo-all           echo all input from script\n"));
@@ -279,6 +280,98 @@ slashUsage(unsigned short int pager)
 }
 
 
+/*
+ * show list of available variables (options) from command line
+ */
+void
+help_variables(void)
+{
+	printf(_("List of specially treated variables.\n"));
+
+	printf(_("psql variables:\n"));
+	printf(_("Usage:\n"));
+	printf(_("  psql --set=NAME=VALUE\n  or \\set NAME VALUE in interactive mode\n\n"));
+
+	printf(_("  AUTOCOMMIT         successful SQL commands are automatically committed\n"));
+	printf(_("  COMP_KEYWORD_CASE  determines which letter case to use when completing an SQL key word\n"));
+	printf(_("  DBNAME             name of currently connected database\n"));
+	printf(_("  ECHO               control what input can be written to standard output [all, queries]\n"));
+	printf(_("  ECHO_HIDDEN        display internal queries executed by backslash commands\n"));
+	printf(_("  ENCODING           current client character set encoding\n"));
+	printf(_("  FETCH_COUNT        the number of result rows to fetch and display at a time\n"
+					 "                     (default: 0=unlimited)\n"));
+	printf(_("  HISTCONTROL        control history list [ignorespace, ignoredups, ignoreboth]\n"));
+	printf(_("  HISTFILE           file name used to store the history list\n"));
+	printf(_("  HISTSIZE           the number of commands to store in the command history\n"));
+	printf(_("  HOST               the currently connected database server\n"));
+	printf(_("  IGNOREEOF          if unset, sending an EOF to interactive session terminates application\n"));
+	printf(_("  LASTOID            the value of last affected OID\n"));
+	printf(_("  ON_ERROR_ROLLBACK  when on, the error doesn't stop transaction (uses implicit SAVEPOINTs)\n"));
+	printf(_("  ON_ERROR_STOP      stop batch execution after error\n"));
+	printf(_("  PORT               server port of the current connection\n"));
+	printf(_("  PROMPT1, PROMPT2, PROMPT3\n"
+					 "                     specify the psql prompt\n"));
+	printf(_("  QUIET              run quietly (same as -q option)\n"));
+	printf(_("  SINGLELINE         end of line terminates SQL command mode (same as -S option)\n"));
+	printf(_("  SINGLESTEP         single-step mode (same as -s option)\n"));
+	printf(_("  USER               the database user currently connected as\n"));
+	printf(_("  VERBOSITY          control verbosity of error reports [default, verbose, terse]\n"));
+
+	printf(_("\nPrinting options:\n"));
+	printf(_("Usage:\n"));
+	printf(_("  psql --pset=NAME[=VALUE]\n  or \\pset NAME [VALUE] in interactive mode\n\n"));
+
+	printf(_("  border             border style (number)\n"));
+	printf(_("  columns            set the target width for the wrapped format\n"));
+	printf(_("  expanded (or x)    toggle expanded output\n"));
+	printf(_("  fieldsep           field separator for unaligned output (default '|')\n"));
+	printf(_("  fieldsep_zero      set field separator in unaligned mode to zero\n"));
+	printf(_("  format             set output format [unaligned, aligned, wrapped, html, latex, ..]\n"));
+	printf(_("  footer             enable or disable display of the table foote [on, off]\n"));
+	printf(_("  linestyle          set the border line drawing style [ascii, old-ascii, unicode]\n"));
+	printf(_("  null               set the string to be printed in place of a null value\n"));
+	printf(_("  numericlocale      enable or disable display of a locale-specific character to separate\n"
+					 "                     groups digits [on, off]\n"));
+	printf(_("  pager              control the use of pager program of query and help output\n"));
+	printf(_("  recordsep          specify the record (line) separator to use in unaligned output format\n"));
+	printf(_("  recordsep_zero     set the record separator to use in unaligned output format to a zero byte.\n"));
+	printf(_("  tableattr (or T)   specify attributies for table tag in html format or proportional\n"
+					 "                     column width of left aligned data type in latex format\n"));
+	printf(_("  title              set the table title for any subsequently printed tables\n"));
+	printf(_("  tuples_only        when on, only actual table data is shown\n"));
+
+	printf(_("\nEnvironment variables:\n"));
+	printf(_("Usage:\n"));
+
+#ifndef WIN32
+	printf(_("  NAME=VALUE [NAME=VALUE] psql ...\n  or \\setenv NAME [VALUE] in interactive mode\n\n"));
+#else
+	printf(_("  set NAME=VALUE\n  psql ...\n  or \\setenv NAME VALUE in interactive mode\n\n"));
+#endif
+
+	printf(_("  COLUMNS            number of columns for wrapped format\n"));
+	printf(_("  PAGER              used pager\n"));
+	printf(_("  PGAPPNAME          same as the application_name connection parameter\n"));
+	printf(_("  PGDATABASE         same as the dbname connection parameter\n"));
+	printf(_("  PGHOST             same as the host connection parameter\n"));
+	printf(_("  PGPORT             same as the port connection parameter\n"));
+	printf(_("  PGUSER             same as the user connection parameter\n"));
+	printf(_("  PGPASSWORD         connection password (not recommended)\n"));
+	printf(_("  PGPASSFILE         password file name\n"));
+	printf(_("  PSQL_EDITOR, EDITOR, VISUAL\n"
+					 "                     editor used by \\e \\ef commands\n"));
+	printf(_("  PSQL_EDITOR_LINE_NUMBER_ARG\n"
+					 "                     style how line number is used in editor\n"));
+	printf(_("  PSQL_HISTORY       alternative location for the command history file\n"));
+	printf(_("  PSQLRC             alternative location of the user's .psqlrc file\n"));
+	printf(_("  SHELL              command executed by the \\! command\n"));
+	printf(_("  TMPDIR             directory for storing temporary files\n"));
+
+	printf(_("\nFor more information consult the psql section in the PostgreSQL\n"
+			 "documentation.\n\n"));
+	printf(_("Report bugs to <pgsql-bugs@postgresql.org>.\n"));
+}
+
 
 /*
  * helpSQL -- help with SQL commands
diff --git a/src/bin/psql/help.h b/src/bin/psql/help.h
index 054d5a4..e7affff 100644
--- a/src/bin/psql/help.h
+++ b/src/bin/psql/help.h
@@ -12,6 +12,8 @@ void		usage(void);
 
 void		slashUsage(unsigned short int pager);
 
+void		help_variables(void);
+
 void		helpSQL(const char *topic, unsigned short int pager);
 
 void		print_copyright(void);
diff --git a/src/bin/psql/startup.c b/src/bin/psql/startup.c
index 45653a1..d911159 100644
--- a/src/bin/psql/startup.c
+++ b/src/bin/psql/startup.c
@@ -383,6 +383,7 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 		{"expanded", no_argument, NULL, 'x'},
 		{"no-psqlrc", no_argument, NULL, 'X'},
 		{"help", no_argument, NULL, '?'},
+		{"help-variables", no_argument, NULL, 1},
 		{NULL, 0, NULL, 0}
 	};
 
@@ -566,6 +567,9 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 					exit(EXIT_FAILURE);
 				}
 				break;
+			case 1:
+				help_variables();
+				exit(EXIT_SUCCESS);
 			default:
 				fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
 						pset.progname);

commit 44ba9d7fc1816dde4605ef59ea68b92b8ceb1c57
Author: Pavel Stehule <pavel.stehule@gooddata.com>
Date:   Sat Jun 28 14:19:47 2014 +0200

    initial

diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml
index ee6ec3a..6a172dc 100644
--- a/doc/src/sgml/ref/psql-ref.sgml
+++ b/doc/src/sgml/ref/psql-ref.sgml
@@ -556,6 +556,15 @@ EOF
       </listitem>
     </varlistentry>
 
+    <varlistentry>
+      <term><option>--help-variables</></term>
+      <listitem>
+      <para>
+      Show help about <application>psql</application> variables,
+      and exit.
+      </para>
+      </listitem>
+    </varlistentry>
   </variablelist>
  </refsect1>
 
diff --git a/src/bin/psql/help.c b/src/bin/psql/help.c
index 3aa3c16..d7da7c3 100644
--- a/src/bin/psql/help.c
+++ b/src/bin/psql/help.c
@@ -78,12 +78,13 @@ usage(void)
 	printf(_("  -f, --file=FILENAME      execute commands from file, then exit\n"));
 	printf(_("  -l, --list               list available databases, then exit\n"));
 	printf(_("  -v, --set=, --variable=NAME=VALUE\n"
-			 "                           set psql variable NAME to VALUE\n"));
+			 "                           set psql variable NAME to VALUE e.g.: -v ON_ERROR_STOP=1\n"));
 	printf(_("  -V, --version            output version information, then exit\n"));
 	printf(_("  -X, --no-psqlrc          do not read startup file (~/.psqlrc)\n"));
 	printf(_("  -1 (\"one\"), --single-transaction\n"
 			 "                           execute as a single transaction (if non-interactive)\n"));
 	printf(_("  -?, --help               show this help, then exit\n"));
+	printf(_("  --help-variables         show a list of all specially treated variables, then exit\n"));
 
 	printf(_("\nInput and output options:\n"));
 	printf(_("  -a, --echo-all           echo all input from script\n"));
@@ -279,6 +280,98 @@ slashUsage(unsigned short int pager)
 }
 
 
+/*
+ * show list of available variables (options) from command line
+ */
+void
+help_variables(void)
+{
+	printf(_("List of specially treated variables.\n"));
+
+	printf(_("psql variables:\n"));
+	printf(_("Usage:\n"));
+	printf(_("  psql --set=NAME=VALUE\n  or \\set NAME VALUE in interactive mode\n\n"));
+
+	printf(_("  AUTOCOMMIT         successful SQL commands are automatically committed\n"));
+	printf(_("  COMP_KEYWORD_CASE  determine which letter case to use when completing an SQL key word\n"));
+	printf(_("  DBNAME             name of currently connected database\n"));
+	printf(_("  ECHO               control what input can be written to standard output [all, queries]\n"));
+	printf(_("  ECHO_HIDDEN        display internal queries executed by backslash commands\n"));
+	printf(_("  ENCODING           current client character set encoding\n"));
+	printf(_("  FETCH_COUNT        the number of result rows to fetch and display at a time\n"
+					 "                     (default: 0=unlimited)\n"));
+	printf(_("  HISTCONTROL        control history list [ignorespace, ignoredups, ignoreboth]\n"));
+	printf(_("  HISTFILE           file name used to store the history list\n"));
+	printf(_("  HISTSIZE           the number of commands to store in the command history\n"));
+	printf(_("  HOST               the currently connected database server\n"));
+	printf(_("  IGNOREEOF          if unset, sending an EOF to interactive session terminates application\n"));
+	printf(_("  LASTOID            the value of last affected OID\n"));
+	printf(_("  ON_ERROR_ROLLBACK  when on, the error doesn't stop transaction (uses implicit SAVEPOINTs)\n"));
+	printf(_("  ON_ERROR_STOP      stop batch execution after error\n"));
+	printf(_("  PORT               server port of the current connection\n"));
+	printf(_("  PROMPT1, PROMPT2, PROMPT3\n"
+					 "                     specify the psql prompt\n"));
+	printf(_("  QUIET              run quietly (same as -q option)\n"));
+	printf(_("  SINGLELINE         end of line terminates SQL command mode (same as -S option)\n"));
+	printf(_("  SINGLESTEP         single-step mode (same as -s option)\n"));
+	printf(_("  USER               the database user currently connected as\n"));
+	printf(_("  VERBOSITY          control verbosity of error reports [default, verbose, terse]\n"));
+
+	printf(_("\nPrinting options:\n"));
+	printf(_("Usage:\n"));
+	printf(_("  psql --pset=NAME[=VALUE]\n  or \\pset NAME [VALUE] in interactive mode\n\n"));
+
+	printf(_("  border             border style (number)\n"));
+	printf(_("  columns            set the target width for the wrapped format\n"));
+	printf(_("  expanded (or x)    toggle expanded output\n"));
+	printf(_("  fieldsep           field separator for unaligned output (default '|')\n"));
+	printf(_("  fieldsep_zero      set field separator in unaligned mode to zero\n"));
+	printf(_("  format             set output format [unaligned, aligned, wrapped, html, latex, ..]\n"));
+	printf(_("  footer             enable or disable display of the table foote [on, off]\n"));
+	printf(_("  linestyle          set the border line drawing style [ascii, old-ascii, unicode]\n"));
+	printf(_("  null               set the string to be printed in place of a null value\n"));
+	printf(_("  numericlocale      enable or disable display of a locale-specific character to separate\n"
+					 "                     groups digits [on, off]\n"));
+	printf(_("  pager              control the use of pager program of query and help output\n"));
+	printf(_("  recordsep          specify the record (line) separator to use in unaligned output format\n"));
+	printf(_("  recordsep_zero     set the record separator to use in unaligned output format to a zero byte.\n"));
+	printf(_("  tableattr (or T)   specify attributies for table tag in html format or proportional\n"
+					 "                     column width of left aligned data type in latex format\n"));
+	printf(_("  title              set the table title for any subsequently printed tables\n"));
+	printf(_("  tuples_only        when on, only actual table data is shown\n"));
+
+	printf(_("\nEnvironment variables:\n"));
+	printf(_("Usage:\n"));
+
+#ifndef WIN32
+	printf(_("  NAME=VALUE [NAME=VALUE] psql ...\n  or \\setenv NAME [VALUE] in interactive mode\n\n"));
+#else
+	printf(_("  set NAME=VALUE\n  psql ...\n  or \\setenv NAME VALUE in interactive mode\n\n"));
+#endif
+
+	printf(_("  COLUMNS            number of columns for wrapped format\n"));
+	printf(_("  PAGER              used pager\n"));
+	printf(_("  PGAPPNAME          same as the application_name connection parameter\n"));
+	printf(_("  PGDATABASE         same as the dbname connection parameter\n"));
+	printf(_("  PGHOST             same as the host connection parameter\n"));
+	printf(_("  PGPORT             same as the port connection parameter\n"));
+	printf(_("  PGUSER             same as the user connection parameter\n"));
+	printf(_("  PGPASSWORD         connection password (not recommended)\n"));
+	printf(_("  PGPASSFILE         password file name\n"));
+	printf(_("  PSQL_EDITOR, EDITOR, VISUAL\n"
+					 "                     editor used by \\e \\ef commands\n"));
+	printf(_("  PSQL_EDITOR_LINE_NUMBER_ARG\n"
+					 "                     style how line number is used in editor\n"));
+	printf(_("  PSQL_HISTORY       alternative location for the command history file\n"));
+	printf(_("  PSQLRC             alternative location of the user's .psqlrc file\n"));
+	printf(_("  SHELL              command executed by the \\! command\n"));
+	printf(_("  TMPDIR             directory for storing temporary files\n"));
+
+	printf(_("\nFor more information consult the psql section in the PostgreSQL\n"
+			 "documentation.\n\n"));
+	printf(_("Report bugs to <pgsql-bugs@postgresql.org>.\n"));
+}
+
 
 /*
  * helpSQL -- help with SQL commands
diff --git a/src/bin/psql/help.h b/src/bin/psql/help.h
index 054d5a4..e7affff 100644
--- a/src/bin/psql/help.h
+++ b/src/bin/psql/help.h
@@ -12,6 +12,8 @@ void		usage(void);
 
 void		slashUsage(unsigned short int pager);
 
+void		help_variables(void);
+
 void		helpSQL(const char *topic, unsigned short int pager);
 
 void		print_copyright(void);
diff --git a/src/bin/psql/startup.c b/src/bin/psql/startup.c
index 45653a1..d911159 100644
--- a/src/bin/psql/startup.c
+++ b/src/bin/psql/startup.c
@@ -383,6 +383,7 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 		{"expanded", no_argument, NULL, 'x'},
 		{"no-psqlrc", no_argument, NULL, 'X'},
 		{"help", no_argument, NULL, '?'},
+		{"help-variables", no_argument, NULL, 1},
 		{NULL, 0, NULL, 0}
 	};
 
@@ -566,6 +567,9 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 					exit(EXIT_FAILURE);
 				}
 				break;
+			case 1:
+				help_variables();
+				exit(EXIT_SUCCESS);
 			default:
 				fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
 						pset.progname);

diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml
index ee6ec3a..6a172dc 100644
--- a/doc/src/sgml/ref/psql-ref.sgml
+++ b/doc/src/sgml/ref/psql-ref.sgml
@@ -556,6 +556,15 @@ EOF
       </listitem>
     </varlistentry>
 
+    <varlistentry>
+      <term><option>--help-variables</></term>
+      <listitem>
+      <para>
+      Show help about <application>psql</application> variables,
+      and exit.
+      </para>
+      </listitem>
+    </varlistentry>
   </variablelist>
  </refsect1>
 
diff --git a/src/bin/psql/help.c b/src/bin/psql/help.c
index 3aa3c16..9ff2dd9 100644
--- a/src/bin/psql/help.c
+++ b/src/bin/psql/help.c
@@ -78,12 +78,13 @@ usage(void)
 	printf(_("  -f, --file=FILENAME      execute commands from file, then exit\n"));
 	printf(_("  -l, --list               list available databases, then exit\n"));
 	printf(_("  -v, --set=, --variable=NAME=VALUE\n"
-			 "                           set psql variable NAME to VALUE\n"));
+			 "                           set psql variable NAME to VALUE e.g.: -v ON_ERROR_STOP=1\n"));
 	printf(_("  -V, --version            output version information, then exit\n"));
 	printf(_("  -X, --no-psqlrc          do not read startup file (~/.psqlrc)\n"));
 	printf(_("  -1 (\"one\"), --single-transaction\n"
 			 "                           execute as a single transaction (if non-interactive)\n"));
 	printf(_("  -?, --help               show this help, then exit\n"));
+	printf(_("  --help-variables         show a list of all specially treated variables, then exit\n"));
 
 	printf(_("\nInput and output options:\n"));
 	printf(_("  -a, --echo-all           echo all input from script\n"));
@@ -279,6 +280,99 @@ slashUsage(unsigned short int pager)
 }
 
 
+/*
+ * show list of available variables (options) from command line
+ */
+void
+help_variables(void)
+{
+	printf(_("List of specially treated variables.\n"));
+
+	printf(_("psql variables:\n"));
+	printf(_("Usage:\n"));
+	printf(_("  psql --set=NAME=VALUE\n  or \\set NAME VALUE in interactive mode\n\n"));
+
+	printf(_("  AUTOCOMMIT         if set, successful SQL commands are automatically committed\n"));
+	printf(_("  COMP_KEYWORD_CASE  determine the case used to complete SQL keywords\n"
+					 "                     [lower, upper, preserve-lower, preserve-upper]\n"));
+	printf(_("  DBNAME             the currently connected database name\n"));
+	printf(_("  ECHO               control what input is written to standard output [all, queries]\n"));
+	printf(_("  ECHO_HIDDEN        display internal queries executed by backslash commands\n"));
+	printf(_("  ENCODING           current client character set encoding\n"));
+	printf(_("  FETCH_COUNT        the number of result rows to fetch and display at a time\n"
+					 "                     (default: 0=unlimited)\n"));
+	printf(_("  HISTCONTROL        control history list [ignorespace, ignoredups, ignoreboth]\n"));
+	printf(_("  HISTFILE           file name used to store the history list\n"));
+	printf(_("  HISTSIZE           the number of commands to store in the command history\n"));
+	printf(_("  HOST               the currently connected database server\n"));
+	printf(_("  IGNOREEOF          if unset, sending an EOF to interactive session terminates application\n"));
+	printf(_("  LASTOID            the value of last affected OID\n"));
+	printf(_("  ON_ERROR_ROLLBACK  if set, an error doesn't stop a transaction (uses implicit SAVEPOINTs)\n"));
+	printf(_("  ON_ERROR_STOP      stop batch execution after error\n"));
+	printf(_("  PORT               server port of the current connection\n"));
+	printf(_("  PROMPT1, PROMPT2, PROMPT3\n"
+					 "                     specify the psql prompt\n"));
+	printf(_("  QUIET              run quietly (same as -q option)\n"));
+	printf(_("  SINGLELINE         end of line terminates SQL command mode (same as -S option)\n"));
+	printf(_("  SINGLESTEP         single-step mode (same as -s option)\n"));
+	printf(_("  USER               the currently connected database user\n"));
+	printf(_("  VERBOSITY          control verbosity of error reports [default, verbose, terse]\n"));
+
+	printf(_("\nPrinting options:\n"));
+	printf(_("Usage:\n"));
+	printf(_("  psql --pset=NAME[=VALUE]\n  or \\pset NAME [VALUE] in interactive mode\n\n"));
+
+	printf(_("  border             border style (number)\n"));
+	printf(_("  columns            set the target width for the wrapped format\n"));
+	printf(_("  expanded (or x)    toggle expanded output\n"));
+	printf(_("  fieldsep           field separator for unaligned output (default '|')\n"));
+	printf(_("  fieldsep_zero      set field separator in unaligned mode to zero\n"));
+	printf(_("  format             set output format [unaligned, aligned, wrapped, html, latex, ..]\n"));
+	printf(_("  footer             enable or disable display of the table footer [on, off]\n"));
+	printf(_("  linestyle          set the border line drawing style [ascii, old-ascii, unicode]\n"));
+	printf(_("  null               set the string to be printed in place of a null value\n"));
+	printf(_("  numericlocale      enable or disable display of a locale-specific character to separate\n"
+					 "                     groups of digits [on, off]\n"));
+	printf(_("  pager              control when an external pager is used [yes, no, always]\n"));
+	printf(_("  recordsep          specify the record (line) separator to use in unaligned output format\n"));
+	printf(_("  recordsep_zero     set the record separator to use in unaligned output format to a zero byte.\n"));
+	printf(_("  tableattr (or T)   specify attributes for table tag in html format or proportional\n"
+					 "                     column width of left aligned data type in latex format\n"));
+	printf(_("  title              set the table title for any subsequently printed tables\n"));
+	printf(_("  tuples_only        if set, only actual table data is shown\n"));
+
+	printf(_("\nEnvironment variables:\n"));
+	printf(_("Usage:\n"));
+
+#ifndef WIN32
+	printf(_("  NAME=VALUE [NAME=VALUE] psql ...\n  or \\setenv NAME [VALUE] in interactive mode\n\n"));
+#else
+	printf(_("  set NAME=VALUE\n  psql ...\n  or \\setenv NAME VALUE in interactive mode\n\n"));
+#endif
+
+	printf(_("  COLUMNS            number of columns for wrapped format\n"));
+	printf(_("  PAGER              name of external pager program\n"));
+	printf(_("  PGAPPNAME          same as the application_name connection parameter\n"));
+	printf(_("  PGDATABASE         same as the dbname connection parameter\n"));
+	printf(_("  PGHOST             same as the host connection parameter\n"));
+	printf(_("  PGPORT             same as the port connection parameter\n"));
+	printf(_("  PGUSER             same as the user connection parameter\n"));
+	printf(_("  PGPASSWORD         connection password (not recommended)\n"));
+	printf(_("  PGPASSFILE         password file name\n"));
+	printf(_("  PSQL_EDITOR, EDITOR, VISUAL\n"
+					 "                     editor used by the \\e and \\ef commands\n"));
+	printf(_("  PSQL_EDITOR_LINENUMBER_ARG\n"
+					 "                     how to specify a line number when invoking the editor\n"));
+	printf(_("  PSQL_HISTORY       alternative location for the command history file\n"));
+	printf(_("  PSQLRC             alternative location for the user's .psqlrc file\n"));
+	printf(_("  SHELL              shell used by the \\! command\n"));
+	printf(_("  TMPDIR             directory for temporary files\n"));
+
+	printf(_("\nFor more information consult the psql section in the PostgreSQL\n"
+			 "documentation.\n\n"));
+	printf(_("Report bugs to <pgsql-bugs@postgresql.org>.\n"));
+}
+
 
 /*
  * helpSQL -- help with SQL commands
diff --git a/src/bin/psql/help.h b/src/bin/psql/help.h
index 054d5a4..e7affff 100644
--- a/src/bin/psql/help.h
+++ b/src/bin/psql/help.h
@@ -12,6 +12,8 @@ void		usage(void);
 
 void		slashUsage(unsigned short int pager);
 
+void		help_variables(void);
+
 void		helpSQL(const char *topic, unsigned short int pager);
 
 void		print_copyright(void);
diff --git a/src/bin/psql/startup.c b/src/bin/psql/startup.c
index 45653a1..d911159 100644
--- a/src/bin/psql/startup.c
+++ b/src/bin/psql/startup.c
@@ -383,6 +383,7 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 		{"expanded", no_argument, NULL, 'x'},
 		{"no-psqlrc", no_argument, NULL, 'X'},
 		{"help", no_argument, NULL, '?'},
+		{"help-variables", no_argument, NULL, 1},
 		{NULL, 0, NULL, 0}
 	};
 
@@ -566,6 +567,9 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 					exit(EXIT_FAILURE);
 				}
 				break;
+			case 1:
+				help_variables();
+				exit(EXIT_SUCCESS);
 			default:
 				fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
 						pset.progname);

commit 1c00470629f31d61886ff9ae95a6855693f358c8
Author: Pavel Stehule <pavel.stehule@gooddata.com>
Date:   Wed Aug 27 22:47:07 2014 +0200

    access to help_variables and usage from psql via psql command

diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml
index 74d4618..6d3189d 100644
--- a/doc/src/sgml/ref/psql-ref.sgml
+++ b/doc/src/sgml/ref/psql-ref.sgml
@@ -568,6 +568,15 @@ EOF
       </listitem>
     </varlistentry>
 
+    <varlistentry>
+      <term><option>--help-variables</></term>
+      <listitem>
+      <para>
+      Show help about <application>psql</application> variables,
+      and exit.
+      </para>
+      </listitem>
+    </varlistentry>
   </variablelist>
  </refsect1>
 
@@ -2572,10 +2581,12 @@ testdb=&gt; <userinput>\setenv LESS -imx4F</userinput>
 
 
       <varlistentry>
-        <term><literal>\?</literal></term>
+        <term><literal>\? [ options | variables ]</literal></term>
         <listitem>
         <para>
-        Shows help information about the backslash commands.
+        Shows help information about the backslash commands.  This command can have a
+        option "variables" or "options" to take help for psql configuration variables
+        or psql command line options.
         </para>
         </listitem>
       </varlistentry>
diff --git a/src/bin/psql/command.c b/src/bin/psql/command.c
index e27ff8c..12cbb20 100644
--- a/src/bin/psql/command.c
+++ b/src/bin/psql/command.c
@@ -1503,7 +1503,19 @@ exec_command(const char *cmd,
 
 	/* \? -- slash command help */
 	else if (strcmp(cmd, "?") == 0)
-		slashUsage(pset.popt.topt.pager);
+	{
+		char	   *opt0 = psql_scan_slash_option(scan_state,
+													OT_NORMAL, NULL, false);
+
+		if (!opt0)
+			slashUsage(pset.popt.topt.pager);
+		else if (strcmp(opt0, "variables") == 0)
+			help_variables(pset.popt.topt.pager);
+		else if (strcmp(opt0, "options") == 0)
+			usage(pset.popt.topt.pager);
+		else
+			slashUsage(pset.popt.topt.pager);
+	}
 
 #if 0
 
diff --git a/src/bin/psql/help.c b/src/bin/psql/help.c
index f8f000f..5e7953d 100644
--- a/src/bin/psql/help.c
+++ b/src/bin/psql/help.c
@@ -46,11 +46,12 @@
 #define ON(var) (var ? _("on") : _("off"))
 
 void
-usage(void)
+usage(unsigned short int pager)
 {
 	const char *env;
 	const char *user;
 	char	   *errstr;
+	FILE	   *output;
 
 	/* Find default user, in case we need it. */
 	user = getenv("PGUSER");
@@ -64,77 +65,82 @@ usage(void)
 		}
 	}
 
-	printf(_("psql is the PostgreSQL interactive terminal.\n\n"));
-	printf(_("Usage:\n"));
-	printf(_("  psql [OPTION]... [DBNAME [USERNAME]]\n\n"));
+	output = PageOutput(59, pager);
+
+	fprintf(output, _("psql is the PostgreSQL interactive terminal.\n\n"));
+	fprintf(output, _("Usage:\n"));
+	fprintf(output, _("  psql [OPTION]... [DBNAME [USERNAME]]\n\n"));
 
-	printf(_("General options:\n"));
+	fprintf(output, _("General options:\n"));
 	/* Display default database */
 	env = getenv("PGDATABASE");
 	if (!env)
 		env = user;
-	printf(_("  -c, --command=COMMAND    run only single command (SQL or internal) and exit\n"));
-	printf(_("  -d, --dbname=DBNAME      database name to connect to (default: \"%s\")\n"), env);
-	printf(_("  -f, --file=FILENAME      execute commands from file, then exit\n"));
-	printf(_("  -l, --list               list available databases, then exit\n"));
-	printf(_("  -v, --set=, --variable=NAME=VALUE\n"
-			 "                           set psql variable NAME to VALUE\n"));
-	printf(_("  -V, --version            output version information, then exit\n"));
-	printf(_("  -X, --no-psqlrc          do not read startup file (~/.psqlrc)\n"));
-	printf(_("  -1 (\"one\"), --single-transaction\n"
+	fprintf(output, _("  -c, --command=COMMAND    run only single command (SQL or internal) and exit\n"));
+	fprintf(output, _("  -d, --dbname=DBNAME      database name to connect to (default: \"%s\")\n"), env);
+	fprintf(output, _("  -f, --file=FILENAME      execute commands from file, then exit\n"));
+	fprintf(output, _("  -l, --list               list available databases, then exit\n"));
+	fprintf(output, _("  -v, --set=, --variable=NAME=VALUE\n"
+			 "                           set psql variable NAME to VALUE e.g.: -v ON_ERROR_STOP=1\n"));
+	fprintf(output, _("  -V, --version            output version information, then exit\n"));
+	fprintf(output, _("  -X, --no-psqlrc          do not read startup file (~/.psqlrc)\n"));
+	fprintf(output, _("  -1 (\"one\"), --single-transaction\n"
 			 "                           execute as a single transaction (if non-interactive)\n"));
-	printf(_("  -?, --help               show this help, then exit\n"));
-
-	printf(_("\nInput and output options:\n"));
-	printf(_("  -a, --echo-all           echo all input from script\n"));
-	printf(_("  -b, --echo-errors        echo failed commands\n"));
-	printf(_("  -e, --echo-queries       echo commands sent to server\n"));
-	printf(_("  -E, --echo-hidden        display queries that internal commands generate\n"));
-	printf(_("  -L, --log-file=FILENAME  send session log to file\n"));
-	printf(_("  -n, --no-readline        disable enhanced command line editing (readline)\n"));
-	printf(_("  -o, --output=FILENAME    send query results to file (or |pipe)\n"));
-	printf(_("  -q, --quiet              run quietly (no messages, only query output)\n"));
-	printf(_("  -s, --single-step        single-step mode (confirm each query)\n"));
-	printf(_("  -S, --single-line        single-line mode (end of line terminates SQL command)\n"));
-
-	printf(_("\nOutput format options:\n"));
-	printf(_("  -A, --no-align           unaligned table output mode\n"));
-	printf(_("  -F, --field-separator=STRING\n"
+	fprintf(output, _("  -?, --help               show this help, then exit\n"));
+	fprintf(output, _("  --help-variables         show a list of all specially treated variables, then exit\n"));
+
+	fprintf(output, _("\nInput and output options:\n"));
+	fprintf(output, _("  -a, --echo-all           echo all input from script\n"));
+	fprintf(output, _("  -b, --echo-errors        echo failed commands\n"));
+	fprintf(output, _("  -e, --echo-queries       echo commands sent to server\n"));
+	fprintf(output, _("  -E, --echo-hidden        display queries that internal commands generate\n"));
+	fprintf(output, _("  -L, --log-file=FILENAME  send session log to file\n"));
+	fprintf(output, _("  -n, --no-readline        disable enhanced command line editing (readline)\n"));
+	fprintf(output, _("  -o, --output=FILENAME    send query results to file (or |pipe)\n"));
+	fprintf(output, _("  -q, --quiet              run quietly (no messages, only query output)\n"));
+	fprintf(output, _("  -s, --single-step        single-step mode (confirm each query)\n"));
+	fprintf(output, _("  -S, --single-line        single-line mode (end of line terminates SQL command)\n"));
+
+	fprintf(output, _("\nOutput format options:\n"));
+	fprintf(output, _("  -A, --no-align           unaligned table output mode\n"));
+	fprintf(output, _("  -F, --field-separator=STRING\n"
 			 "                           field separator for unaligned output (default: \"%s\")\n"),
 		   DEFAULT_FIELD_SEP);
-	printf(_("  -H, --html               HTML table output mode\n"));
-	printf(_("  -P, --pset=VAR[=ARG]     set printing option VAR to ARG (see \\pset command)\n"));
-	printf(_("  -R, --record-separator=STRING\n"
+	fprintf(output, _("  -H, --html               HTML table output mode\n"));
+	fprintf(output, _("  -P, --pset=VAR[=ARG]     set printing option VAR to ARG (see \\pset command)\n"));
+	fprintf(output, _("  -R, --record-separator=STRING\n"
 			 "                           record separator for unaligned output (default: newline)\n"));
-	printf(_("  -t, --tuples-only        print rows only\n"));
-	printf(_("  -T, --table-attr=TEXT    set HTML table tag attributes (e.g., width, border)\n"));
-	printf(_("  -x, --expanded           turn on expanded table output\n"));
-	printf(_("  -z, --field-separator-zero\n"
+	fprintf(output, _("  -t, --tuples-only        print rows only\n"));
+	fprintf(output, _("  -T, --table-attr=TEXT    set HTML table tag attributes (e.g., width, border)\n"));
+	fprintf(output, _("  -x, --expanded           turn on expanded table output\n"));
+	fprintf(output, _("  -z, --field-separator-zero\n"
 			 "                           set field separator for unaligned output to zero byte\n"));
-	printf(_("  -0, --record-separator-zero\n"
+	fprintf(output, _("  -0, --record-separator-zero\n"
 			 "                           set record separator for unaligned output to zero byte\n"));
 
-	printf(_("\nConnection options:\n"));
+	fprintf(output, _("\nConnection options:\n"));
 	/* Display default host */
 	env = getenv("PGHOST");
-	printf(_("  -h, --host=HOSTNAME      database server host or socket directory (default: \"%s\")\n"),
+	fprintf(output, _("  -h, --host=HOSTNAME      database server host or socket directory (default: \"%s\")\n"),
 		   env ? env : _("local socket"));
 	/* Display default port */
 	env = getenv("PGPORT");
-	printf(_("  -p, --port=PORT          database server port (default: \"%s\")\n"),
+	fprintf(output, _("  -p, --port=PORT          database server port (default: \"%s\")\n"),
 		   env ? env : DEF_PGPORT_STR);
 	/* Display default user */
 	env = getenv("PGUSER");
 	if (!env)
 		env = user;
-	printf(_("  -U, --username=USERNAME  database user name (default: \"%s\")\n"), env);
-	printf(_("  -w, --no-password        never prompt for password\n"));
-	printf(_("  -W, --password           force password prompt (should happen automatically)\n"));
+	fprintf(output, _("  -U, --username=USERNAME  database user name (default: \"%s\")\n"), env);
+	fprintf(output, _("  -w, --no-password        never prompt for password\n"));
+	fprintf(output, _("  -W, --password           force password prompt (should happen automatically)\n"));
 
-	printf(_("\nFor more information, type \"\\?\" (for internal commands) or \"\\help\" (for SQL\n"
+	fprintf(output, _("\nFor more information, type \"\\?\" (for internal commands) or \"\\help\" (for SQL\n"
 			 "commands) from within psql, or consult the psql section in the PostgreSQL\n"
 			 "documentation.\n\n"));
-	printf(_("Report bugs to <pgsql-bugs@postgresql.org>.\n"));
+	fprintf(output, _("Report bugs to <pgsql-bugs@postgresql.org>.\n"));
+
+	ClosePager(output);
 }
 
 
@@ -159,11 +165,18 @@ slashUsage(unsigned short int pager)
 	fprintf(output, _("  \\copyright             show PostgreSQL usage and distribution terms\n"));
 	fprintf(output, _("  \\g [FILE] or ;         execute query (and send results to file or |pipe)\n"));
 	fprintf(output, _("  \\gset [PREFIX]         execute query and store results in psql variables\n"));
-	fprintf(output, _("  \\h [NAME]              help on syntax of SQL commands, * for all commands\n"));
 	fprintf(output, _("  \\q                     quit psql\n"));
 	fprintf(output, _("  \\watch [SEC]           execute query every SEC seconds\n"));
 	fprintf(output, "\n");
 
+	fprintf(output, _("Help\n"));
+
+	fprintf(output, _("  \\?                     description of all psql commands\n"));
+	fprintf(output, _("  \\? options             description of psql options\n"));
+	fprintf(output, _("  \\? variables           description of all psql configuration variables\n"));
+	fprintf(output, _("  \\h [NAME]              help on syntax of SQL commands, * for all commands\n"));
+	fprintf(output, "\n");
+
 	fprintf(output, _("Query Buffer\n"));
 	fprintf(output, _("  \\e [FILE] [LINE]       edit the query buffer (or file) with external editor\n"));
 	fprintf(output, _("  \\ef [FUNCNAME [LINE]]  edit function definition with external editor\n"));
@@ -280,6 +293,105 @@ slashUsage(unsigned short int pager)
 }
 
 
+/*
+ * show list of available variables (options) from command line
+ */
+void
+help_variables(unsigned short int pager)
+{
+	FILE	   *output;
+
+	output = PageOutput(83, pager);
+
+	fprintf(output, _("List of specially treated variables.\n"));
+
+	fprintf(output, _("psql variables:\n"));
+	fprintf(output, _("Usage:\n"));
+	fprintf(output, _("  psql --set=NAME=VALUE\n  or \\set NAME VALUE in interactive mode\n\n"));
+
+	fprintf(output, _("  AUTOCOMMIT         if set, successful SQL commands are automatically committed\n"));
+	fprintf(output, _("  COMP_KEYWORD_CASE  determine the case used to complete SQL keywords\n"
+					 "                     [lower, upper, preserve-lower, preserve-upper]\n"));
+	fprintf(output, _("  DBNAME             the currently connected database name\n"));
+	fprintf(output, _("  ECHO               control what input is written to standard output [all, queries]\n"));
+	fprintf(output, _("  ECHO_HIDDEN        display internal queries executed by backslash commands\n"));
+	fprintf(output, _("  ENCODING           current client character set encoding\n"));
+	fprintf(output, _("  FETCH_COUNT        the number of result rows to fetch and display at a time\n"
+					 "                     (default: 0=unlimited)\n"));
+	fprintf(output, _("  HISTCONTROL        control history list [ignorespace, ignoredups, ignoreboth]\n"));
+	fprintf(output, _("  HISTFILE           file name used to store the history list\n"));
+	fprintf(output, _("  HISTSIZE           the number of commands to store in the command history\n"));
+	fprintf(output, _("  HOST               the currently connected database server\n"));
+	fprintf(output, _("  IGNOREEOF          if unset, sending an EOF to interactive session terminates application\n"));
+	fprintf(output, _("  LASTOID            the value of last affected OID\n"));
+	fprintf(output, _("  ON_ERROR_ROLLBACK  if set, an error doesn't stop a transaction (uses implicit SAVEPOINTs)\n"));
+	fprintf(output, _("  ON_ERROR_STOP      stop batch execution after error\n"));
+	fprintf(output, _("  PORT               server port of the current connection\n"));
+	fprintf(output, _("  PROMPT1, PROMPT2, PROMPT3\n"
+					 "                     specify the psql prompt\n"));
+	fprintf(output, _("  QUIET              run quietly (same as -q option)\n"));
+	fprintf(output, _("  SINGLELINE         end of line terminates SQL command mode (same as -S option)\n"));
+	fprintf(output, _("  SINGLESTEP         single-step mode (same as -s option)\n"));
+	fprintf(output, _("  USER               the currently connected database user\n"));
+	fprintf(output, _("  VERBOSITY          control verbosity of error reports [default, verbose, terse]\n"));
+
+	fprintf(output, _("\nPrinting options:\n"));
+	fprintf(output, _("Usage:\n"));
+	fprintf(output, _("  psql --pset=NAME[=VALUE]\n  or \\pset NAME [VALUE] in interactive mode\n\n"));
+
+	fprintf(output, _("  border             border style (number)\n"));
+	fprintf(output, _("  columns            set the target width for the wrapped format\n"));
+	fprintf(output, _("  expanded (or x)    toggle expanded output\n"));
+	fprintf(output, _("  fieldsep           field separator for unaligned output (default '|')\n"));
+	fprintf(output, _("  fieldsep_zero      set field separator in unaligned mode to zero\n"));
+	fprintf(output, _("  format             set output format [unaligned, aligned, wrapped, html, latex, ..]\n"));
+	fprintf(output, _("  footer             enable or disable display of the table footer [on, off]\n"));
+	fprintf(output, _("  linestyle          set the border line drawing style [ascii, old-ascii, unicode]\n"));
+	fprintf(output, _("  null               set the string to be printed in place of a null value\n"));
+	fprintf(output, _("  numericlocale      enable or disable display of a locale-specific character to separate\n"
+					 "                     groups of digits [on, off]\n"));
+	fprintf(output, _("  pager              control when an external pager is used [yes, no, always]\n"));
+	fprintf(output, _("  recordsep          specify the record (line) separator to use in unaligned output format\n"));
+	fprintf(output, _("  recordsep_zero     set the record separator to use in unaligned output format to a zero byte.\n"));
+	fprintf(output, _("  tableattr (or T)   specify attributes for table tag in html format or proportional\n"
+					 "                     column width of left aligned data type in latex format\n"));
+	fprintf(output, _("  title              set the table title for any subsequently printed tables\n"));
+	fprintf(output, _("  tuples_only        if set, only actual table data is shown\n"));
+
+	fprintf(output, _("\nEnvironment variables:\n"));
+	fprintf(output, _("Usage:\n"));
+
+#ifndef WIN32
+	fprintf(output, _("  NAME=VALUE [NAME=VALUE] psql ...\n  or \\setenv NAME [VALUE] in interactive mode\n\n"));
+#else
+	fprintf(output, _("  set NAME=VALUE\n  psql ...\n  or \\setenv NAME VALUE in interactive mode\n\n"));
+#endif
+
+	fprintf(output, _("  COLUMNS            number of columns for wrapped format\n"));
+	fprintf(output, _("  PAGER              name of external pager program\n"));
+	fprintf(output, _("  PGAPPNAME          same as the application_name connection parameter\n"));
+	fprintf(output, _("  PGDATABASE         same as the dbname connection parameter\n"));
+	fprintf(output, _("  PGHOST             same as the host connection parameter\n"));
+	fprintf(output, _("  PGPORT             same as the port connection parameter\n"));
+	fprintf(output, _("  PGUSER             same as the user connection parameter\n"));
+	fprintf(output, _("  PGPASSWORD         connection password (not recommended)\n"));
+	fprintf(output, _("  PGPASSFILE         password file name\n"));
+	fprintf(output, _("  PSQL_EDITOR, EDITOR, VISUAL\n"
+					 "                     editor used by the \\e and \\ef commands\n"));
+	fprintf(output, _("  PSQL_EDITOR_LINENUMBER_ARG\n"
+					 "                     how to specify a line number when invoking the editor\n"));
+	fprintf(output, _("  PSQL_HISTORY       alternative location for the command history file\n"));
+	fprintf(output, _("  PSQLRC             alternative location for the user's .psqlrc file\n"));
+	fprintf(output, _("  SHELL              shell used by the \\! command\n"));
+	fprintf(output, _("  TMPDIR             directory for temporary files\n"));
+
+	fprintf(output, _("\nFor more information consult the psql section in the PostgreSQL\n"
+			 "documentation.\n\n"));
+	fprintf(output, _("Report bugs to <pgsql-bugs@postgresql.org>.\n"));
+
+	ClosePager(output);
+}
+
 
 /*
  * helpSQL -- help with SQL commands
diff --git a/src/bin/psql/help.h b/src/bin/psql/help.h
index 054d5a4..bab360d 100644
--- a/src/bin/psql/help.h
+++ b/src/bin/psql/help.h
@@ -8,10 +8,12 @@
 #ifndef HELP_H
 #define HELP_H
 
-void		usage(void);
+void		usage(unsigned short int pager);
 
 void		slashUsage(unsigned short int pager);
 
+void		help_variables(unsigned short int pager);
+
 void		helpSQL(const char *topic, unsigned short int pager);
 
 void		print_copyright(void);
diff --git a/src/bin/psql/startup.c b/src/bin/psql/startup.c
index 5a397e8..af68e13 100644
--- a/src/bin/psql/startup.c
+++ b/src/bin/psql/startup.c
@@ -77,6 +77,8 @@ static void process_psqlrc_file(char *filename);
 static void showVersion(void);
 static void EstablishVariableSpace(void);
 
+#define NOPAGER		0
+
 /*
  *
  * main
@@ -97,7 +99,7 @@ main(int argc, char *argv[])
 	{
 		if (strcmp(argv[1], "--help") == 0 || strcmp(argv[1], "-?") == 0)
 		{
-			usage();
+			usage(NOPAGER);
 			exit(EXIT_SUCCESS);
 		}
 		if (strcmp(argv[1], "--version") == 0 || strcmp(argv[1], "-V") == 0)
@@ -384,6 +386,7 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 		{"expanded", no_argument, NULL, 'x'},
 		{"no-psqlrc", no_argument, NULL, 'X'},
 		{"help", no_argument, NULL, '?'},
+		{"help-variables", no_argument, NULL, 1},
 		{NULL, 0, NULL, 0}
 	};
 
@@ -559,7 +562,7 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 				/* Actual help option given */
 				if (strcmp(argv[optind - 1], "--help") == 0 || strcmp(argv[optind - 1], "-?") == 0)
 				{
-					usage();
+					usage(NOPAGER);
 					exit(EXIT_SUCCESS);
 				}
 				/* unknown option reported by getopt */
@@ -570,6 +573,9 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 					exit(EXIT_FAILURE);
 				}
 				break;
+			case 1:
+				help_variables(NOPAGER);
+				exit(EXIT_SUCCESS);
 			default:
 				fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
 						pset.progname);
diff --git a/src/bin/psql/tab-complete.c b/src/bin/psql/tab-complete.c
index 76b2b04..7a94fa8 100644
--- a/src/bin/psql/tab-complete.c
+++ b/src/bin/psql/tab-complete.c
@@ -3513,6 +3513,13 @@ psql_completion(const char *text, int start, int end)
 
 /* Backslash commands */
 /* TODO:  \dc \dd \dl */
+	else if (strcmp(prev_wd, "\\?") == 0)
+	{
+		static const char *const my_list[] =
+		{"options", "variables", NULL};
+
+		COMPLETE_WITH_LIST_CS(my_list);
+	}
 	else if (strcmp(prev_wd, "\\connect") == 0 || strcmp(prev_wd, "\\c") == 0)
 		COMPLETE_WITH_QUERY(Query_for_list_of_databases);
 

0001-help-variables-11.patch

diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml
index 6d3189d..b14db45 100644
--- a/doc/src/sgml/ref/psql-ref.sgml
+++ b/doc/src/sgml/ref/psql-ref.sgml
@@ -2581,12 +2581,15 @@ testdb=&gt; <userinput>\setenv LESS -imx4F</userinput>
 
 
       <varlistentry>
-        <term><literal>\? [ options | variables ]</literal></term>
+        <term><literal>\? [ <replaceable class="parameter">topic</replaceable> ]</literal></term>
         <listitem>
         <para>
-        Shows help information about the backslash commands.  This command can have a
-        option "variables" or "options" to take help for psql configuration variables
-        or psql command line options.
+        Shows help information. The parameter
+        <replaceable class="parameter">topic</replaceable> can be
+        <literal>commands</> (the default) to show help about backslash
+        commands, <literal>options</> to show information about commandline
+        arguments, or <literal>variables</> to show information about
+        variables influencing <application>psql</>'s behaviour or display.
         </para>
         </listitem>
       </varlistentry>
diff --git a/src/bin/psql/command.c b/src/bin/psql/command.c
index 12cbb20..7e4626c 100644
--- a/src/bin/psql/command.c
+++ b/src/bin/psql/command.c
@@ -1507,12 +1507,12 @@ exec_command(const char *cmd,
 		char	   *opt0 = psql_scan_slash_option(scan_state,
 													OT_NORMAL, NULL, false);
 
-		if (!opt0)
+		if (!opt0 || strcmp(opt0, "commands") == 0)
 			slashUsage(pset.popt.topt.pager);
-		else if (strcmp(opt0, "variables") == 0)
-			help_variables(pset.popt.topt.pager);
 		else if (strcmp(opt0, "options") == 0)
 			usage(pset.popt.topt.pager);
+		else if (strcmp(opt0, "variables") == 0)
+			helpVariables(pset.popt.topt.pager);
 		else
 			slashUsage(pset.popt.topt.pager);
 	}
diff --git a/src/bin/psql/help.c b/src/bin/psql/help.c
index 5e7953d..e0d1d13 100644
--- a/src/bin/psql/help.c
+++ b/src/bin/psql/help.c
@@ -171,7 +171,7 @@ slashUsage(unsigned short int pager)
 
 	fprintf(output, _("Help\n"));
 
-	fprintf(output, _("  \\?                     description of all psql commands\n"));
+	fprintf(output, _("  \\? [commands]          description of all psql commands\n"));
 	fprintf(output, _("  \\? options             description of psql options\n"));
 	fprintf(output, _("  \\? variables           description of all psql configuration variables\n"));
 	fprintf(output, _("  \\h [NAME]              help on syntax of SQL commands, * for all commands\n"));
@@ -294,10 +294,12 @@ slashUsage(unsigned short int pager)
 
 
 /*
- * show list of available variables (options) from command line
+ * helpVariables
+ *
+ * Show list of available variables (options).
  */
 void
-help_variables(unsigned short int pager)
+helpVariables(unsigned short int pager)
 {
 	FILE	   *output;
 
@@ -335,7 +337,7 @@ help_variables(unsigned short int pager)
 	fprintf(output, _("  USER               the currently connected database user\n"));
 	fprintf(output, _("  VERBOSITY          control verbosity of error reports [default, verbose, terse]\n"));
 
-	fprintf(output, _("\nPrinting options:\n"));
+	fprintf(output, _("\nDisplay influencing variables:\n"));
 	fprintf(output, _("Usage:\n"));
 	fprintf(output, _("  psql --pset=NAME[=VALUE]\n  or \\pset NAME [VALUE] in interactive mode\n\n"));
 
diff --git a/src/bin/psql/help.h b/src/bin/psql/help.h
index bab360d..3ad374a 100644
--- a/src/bin/psql/help.h
+++ b/src/bin/psql/help.h
@@ -12,7 +12,7 @@ void		usage(unsigned short int pager);
 
 void		slashUsage(unsigned short int pager);
 
-void		help_variables(unsigned short int pager);
+void		helpVariables(unsigned short int pager);
 
 void		helpSQL(const char *topic, unsigned short int pager);
 
diff --git a/src/bin/psql/startup.c b/src/bin/psql/startup.c
index af68e13..0651588 100644
--- a/src/bin/psql/startup.c
+++ b/src/bin/psql/startup.c
@@ -574,7 +574,7 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 				}
 				break;
 			case 1:
-				help_variables(NOPAGER);
+				helpVariables(NOPAGER);
 				exit(EXIT_SUCCESS);
 			default:
 				fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
diff --git a/src/bin/psql/tab-complete.c b/src/bin/psql/tab-complete.c
index 7a94fa8..da1b984 100644
--- a/src/bin/psql/tab-complete.c
+++ b/src/bin/psql/tab-complete.c
@@ -3516,7 +3516,7 @@ psql_completion(const char *text, int start, int end)
 	else if (strcmp(prev_wd, "\\?") == 0)
 	{
 		static const char *const my_list[] =
-		{"options", "variables", NULL};
+		{"commands","options", "variables", NULL};
 
 		COMPLETE_WITH_LIST_CS(my_list);
 	}

commit 17a0708a0466cc8ff9e8debd0a7e9062eebe3a61
Author: Pavel Stehule <pavel.stehule@gooddata.com>
Date:   Wed Aug 27 22:47:07 2014 +0200

    access to help_variables and usage from psql via psql command

diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml
index db314c3..9bb14e9 100644
--- a/doc/src/sgml/ref/psql-ref.sgml
+++ b/doc/src/sgml/ref/psql-ref.sgml
@@ -568,6 +568,15 @@ EOF
       </listitem>
     </varlistentry>
 
+    <varlistentry>
+      <term><option>--help-variables</></term>
+      <listitem>
+      <para>
+      Show help about <application>psql</application> variables,
+      and exit.
+      </para>
+      </listitem>
+    </varlistentry>
   </variablelist>
  </refsect1>
 
@@ -2572,10 +2581,12 @@ testdb=&gt; <userinput>\setenv LESS -imx4F</userinput>
 
 
       <varlistentry>
-        <term><literal>\?</literal></term>
+        <term><literal>\? [ options | variables ]</literal></term>
         <listitem>
         <para>
-        Shows help information about the backslash commands.
+        Shows help information about the backslash commands.  This command can have a
+        option "variables" or "options" to take help for psql configuration variables
+        or psql command line options.
         </para>
         </listitem>
       </varlistentry>
diff --git a/src/bin/psql/command.c b/src/bin/psql/command.c
index e16b4d5..987a79f 100644
--- a/src/bin/psql/command.c
+++ b/src/bin/psql/command.c
@@ -1503,7 +1503,19 @@ exec_command(const char *cmd,
 
 	/* \? -- slash command help */
 	else if (strcmp(cmd, "?") == 0)
-		slashUsage(pset.popt.topt.pager);
+	{
+		char	   *opt0 = psql_scan_slash_option(scan_state,
+													OT_NORMAL, NULL, false);
+
+		if (!opt0)
+			slashUsage(pset.popt.topt.pager);
+		else if (strcmp(opt0, "variables") == 0)
+			help_variables(pset.popt.topt.pager);
+		else if (strcmp(opt0, "options") == 0)
+			usage(pset.popt.topt.pager);
+		else
+			slashUsage(pset.popt.topt.pager);
+	}
 
 #if 0
 
diff --git a/src/bin/psql/help.c b/src/bin/psql/help.c
index f8f000f..4f29f2a 100644
--- a/src/bin/psql/help.c
+++ b/src/bin/psql/help.c
@@ -46,11 +46,12 @@
 #define ON(var) (var ? _("on") : _("off"))
 
 void
-usage(void)
+usage(unsigned short int pager)
 {
 	const char *env;
 	const char *user;
 	char	   *errstr;
+	FILE	   *output;
 
 	/* Find default user, in case we need it. */
 	user = getenv("PGUSER");
@@ -64,77 +65,82 @@ usage(void)
 		}
 	}
 
-	printf(_("psql is the PostgreSQL interactive terminal.\n\n"));
-	printf(_("Usage:\n"));
-	printf(_("  psql [OPTION]... [DBNAME [USERNAME]]\n\n"));
+	output = PageOutput(59, pager);
+
+	fprintf(output, _("psql is the PostgreSQL interactive terminal.\n\n"));
+	fprintf(output, _("Usage:\n"));
+	fprintf(output, _("  psql [OPTION]... [DBNAME [USERNAME]]\n\n"));
 
-	printf(_("General options:\n"));
+	fprintf(output, _("General options:\n"));
 	/* Display default database */
 	env = getenv("PGDATABASE");
 	if (!env)
 		env = user;
-	printf(_("  -c, --command=COMMAND    run only single command (SQL or internal) and exit\n"));
-	printf(_("  -d, --dbname=DBNAME      database name to connect to (default: \"%s\")\n"), env);
-	printf(_("  -f, --file=FILENAME      execute commands from file, then exit\n"));
-	printf(_("  -l, --list               list available databases, then exit\n"));
-	printf(_("  -v, --set=, --variable=NAME=VALUE\n"
-			 "                           set psql variable NAME to VALUE\n"));
-	printf(_("  -V, --version            output version information, then exit\n"));
-	printf(_("  -X, --no-psqlrc          do not read startup file (~/.psqlrc)\n"));
-	printf(_("  -1 (\"one\"), --single-transaction\n"
+	fprintf(output, _("  -c, --command=COMMAND    run only single command (SQL or internal) and exit\n"));
+	fprintf(output, _("  -d, --dbname=DBNAME      database name to connect to (default: \"%s\")\n"), env);
+	fprintf(output, _("  -f, --file=FILENAME      execute commands from file, then exit\n"));
+	fprintf(output, _("  -l, --list               list available databases, then exit\n"));
+	fprintf(output, _("  -v, --set=, --variable=NAME=VALUE\n"
+			 "                           set psql variable NAME to VALUE e.g.: -v ON_ERROR_STOP=1\n"));
+	fprintf(output, _("  -V, --version            output version information, then exit\n"));
+	fprintf(output, _("  -X, --no-psqlrc          do not read startup file (~/.psqlrc)\n"));
+	fprintf(output, _("  -1 (\"one\"), --single-transaction\n"
 			 "                           execute as a single transaction (if non-interactive)\n"));
-	printf(_("  -?, --help               show this help, then exit\n"));
-
-	printf(_("\nInput and output options:\n"));
-	printf(_("  -a, --echo-all           echo all input from script\n"));
-	printf(_("  -b, --echo-errors        echo failed commands\n"));
-	printf(_("  -e, --echo-queries       echo commands sent to server\n"));
-	printf(_("  -E, --echo-hidden        display queries that internal commands generate\n"));
-	printf(_("  -L, --log-file=FILENAME  send session log to file\n"));
-	printf(_("  -n, --no-readline        disable enhanced command line editing (readline)\n"));
-	printf(_("  -o, --output=FILENAME    send query results to file (or |pipe)\n"));
-	printf(_("  -q, --quiet              run quietly (no messages, only query output)\n"));
-	printf(_("  -s, --single-step        single-step mode (confirm each query)\n"));
-	printf(_("  -S, --single-line        single-line mode (end of line terminates SQL command)\n"));
-
-	printf(_("\nOutput format options:\n"));
-	printf(_("  -A, --no-align           unaligned table output mode\n"));
-	printf(_("  -F, --field-separator=STRING\n"
+	fprintf(output, _("  -?, --help               show this help, then exit\n"));
+	fprintf(output, _("  --help-variables         show a list of all specially treated variables, then exit\n"));
+
+	fprintf(output, _("\nInput and output options:\n"));
+	fprintf(output, _("  -a, --echo-all           echo all input from script\n"));
+	fprintf(output, _("  -b, --echo-errors        echo failed commands\n"));
+	fprintf(output, _("  -e, --echo-queries       echo commands sent to server\n"));
+	fprintf(output, _("  -E, --echo-hidden        display queries that internal commands generate\n"));
+	fprintf(output, _("  -L, --log-file=FILENAME  send session log to file\n"));
+	fprintf(output, _("  -n, --no-readline        disable enhanced command line editing (readline)\n"));
+	fprintf(output, _("  -o, --output=FILENAME    send query results to file (or |pipe)\n"));
+	fprintf(output, _("  -q, --quiet              run quietly (no messages, only query output)\n"));
+	fprintf(output, _("  -s, --single-step        single-step mode (confirm each query)\n"));
+	fprintf(output, _("  -S, --single-line        single-line mode (end of line terminates SQL command)\n"));
+
+	fprintf(output, _("\nOutput format options:\n"));
+	fprintf(output, _("  -A, --no-align           unaligned table output mode\n"));
+	fprintf(output, _("  -F, --field-separator=STRING\n"
 			 "                           field separator for unaligned output (default: \"%s\")\n"),
 		   DEFAULT_FIELD_SEP);
-	printf(_("  -H, --html               HTML table output mode\n"));
-	printf(_("  -P, --pset=VAR[=ARG]     set printing option VAR to ARG (see \\pset command)\n"));
-	printf(_("  -R, --record-separator=STRING\n"
+	fprintf(output, _("  -H, --html               HTML table output mode\n"));
+	fprintf(output, _("  -P, --pset=VAR[=ARG]     set printing option VAR to ARG (see \\pset command)\n"));
+	fprintf(output, _("  -R, --record-separator=STRING\n"
 			 "                           record separator for unaligned output (default: newline)\n"));
-	printf(_("  -t, --tuples-only        print rows only\n"));
-	printf(_("  -T, --table-attr=TEXT    set HTML table tag attributes (e.g., width, border)\n"));
-	printf(_("  -x, --expanded           turn on expanded table output\n"));
-	printf(_("  -z, --field-separator-zero\n"
+	fprintf(output, _("  -t, --tuples-only        print rows only\n"));
+	fprintf(output, _("  -T, --table-attr=TEXT    set HTML table tag attributes (e.g., width, border)\n"));
+	fprintf(output, _("  -x, --expanded           turn on expanded table output\n"));
+	fprintf(output, _("  -z, --field-separator-zero\n"
 			 "                           set field separator for unaligned output to zero byte\n"));
-	printf(_("  -0, --record-separator-zero\n"
+	fprintf(output, _("  -0, --record-separator-zero\n"
 			 "                           set record separator for unaligned output to zero byte\n"));
 
-	printf(_("\nConnection options:\n"));
+	fprintf(output, _("\nConnection options:\n"));
 	/* Display default host */
 	env = getenv("PGHOST");
-	printf(_("  -h, --host=HOSTNAME      database server host or socket directory (default: \"%s\")\n"),
+	fprintf(output, _("  -h, --host=HOSTNAME      database server host or socket directory (default: \"%s\")\n"),
 		   env ? env : _("local socket"));
 	/* Display default port */
 	env = getenv("PGPORT");
-	printf(_("  -p, --port=PORT          database server port (default: \"%s\")\n"),
+	fprintf(output, _("  -p, --port=PORT          database server port (default: \"%s\")\n"),
 		   env ? env : DEF_PGPORT_STR);
 	/* Display default user */
 	env = getenv("PGUSER");
 	if (!env)
 		env = user;
-	printf(_("  -U, --username=USERNAME  database user name (default: \"%s\")\n"), env);
-	printf(_("  -w, --no-password        never prompt for password\n"));
-	printf(_("  -W, --password           force password prompt (should happen automatically)\n"));
+	fprintf(output, _("  -U, --username=USERNAME  database user name (default: \"%s\")\n"), env);
+	fprintf(output, _("  -w, --no-password        never prompt for password\n"));
+	fprintf(output, _("  -W, --password           force password prompt (should happen automatically)\n"));
 
-	printf(_("\nFor more information, type \"\\?\" (for internal commands) or \"\\help\" (for SQL\n"
+	fprintf(output, _("\nFor more information, type \"\\?\" (for internal commands) or \"\\help\" (for SQL\n"
 			 "commands) from within psql, or consult the psql section in the PostgreSQL\n"
 			 "documentation.\n\n"));
-	printf(_("Report bugs to <pgsql-bugs@postgresql.org>.\n"));
+	fprintf(output, _("Report bugs to <pgsql-bugs@postgresql.org>.\n"));
+
+	ClosePager(output);
 }
 
 
@@ -159,11 +165,18 @@ slashUsage(unsigned short int pager)
 	fprintf(output, _("  \\copyright             show PostgreSQL usage and distribution terms\n"));
 	fprintf(output, _("  \\g [FILE] or ;         execute query (and send results to file or |pipe)\n"));
 	fprintf(output, _("  \\gset [PREFIX]         execute query and store results in psql variables\n"));
-	fprintf(output, _("  \\h [NAME]              help on syntax of SQL commands, * for all commands\n"));
 	fprintf(output, _("  \\q                     quit psql\n"));
 	fprintf(output, _("  \\watch [SEC]           execute query every SEC seconds\n"));
 	fprintf(output, "\n");
 
+	fprintf(output, _("Help\n"));
+
+	fprintf(output, _("  \\?                     description of all psql commands\n"));
+	fprintf(output, _("  \\? options             description of psql options\n"));
+	fprintf(output, _("  \\? variables           description of all psql configuration variables\n"));
+	fprintf(output, _("  \\h [NAME]              help on syntax of SQL commands, * for all commands\n"));
+	fprintf(output, "\n");
+
 	fprintf(output, _("Query Buffer\n"));
 	fprintf(output, _("  \\e [FILE] [LINE]       edit the query buffer (or file) with external editor\n"));
 	fprintf(output, _("  \\ef [FUNCNAME [LINE]]  edit function definition with external editor\n"));
@@ -280,6 +293,108 @@ slashUsage(unsigned short int pager)
 }
 
 
+/*
+ * show list of available variables (options) from command line
+ */
+void
+help_variables(unsigned short int pager)
+{
+	FILE	   *output;
+
+	output = PageOutput(86, pager);
+
+	fprintf(output, _("List of specially treated variables.\n"));
+
+	fprintf(output, _("psql variables:\n"));
+	fprintf(output, _("Usage:\n"));
+	fprintf(output, _("  psql --set=NAME=VALUE\n  or \\set NAME VALUE in interactive mode\n\n"));
+
+	fprintf(output, _("  AUTOCOMMIT         if set, successful SQL commands are automatically committed\n"));
+	fprintf(output, _("  COMP_KEYWORD_CASE  determine the case used to complete SQL keywords\n"
+					 "                     [lower, upper, preserve-lower, preserve-upper]\n"));
+	fprintf(output, _("  DBNAME             the currently connected database name\n"));
+	fprintf(output, _("  ECHO               control what input is written to standard output\n"
+					 "                     [all, errors, none, queries]\n"));
+	fprintf(output, _("  ECHO_HIDDEN        display internal queries executed by backslash commands when it is set\n"
+					 "                     or with [noexec] just show without execution\n"));
+	fprintf(output, _("  ENCODING           current client character set encoding\n"));
+	fprintf(output, _("  FETCH_COUNT        the number of result rows to fetch and display at a time\n"
+					 "                     (default: 0=unlimited)\n"));
+	fprintf(output, _("  HISTCONTROL        control history list [ignorespace, ignoredups, ignoreboth]\n"));
+	fprintf(output, _("  HISTFILE           file name used to store the history list\n"));
+	fprintf(output, _("  HISTSIZE           the number of commands to store in the command history\n"));
+	fprintf(output, _("  HOST               the currently connected database server\n"));
+	fprintf(output, _("  IGNOREEOF          if unset, sending an EOF to interactive session terminates application\n"));
+	fprintf(output, _("  LASTOID            the value of last affected OID\n"));
+	fprintf(output, _("  ON_ERROR_ROLLBACK  if set, an error doesn't stop a transaction (uses implicit SAVEPOINTs)\n"));
+	fprintf(output, _("  ON_ERROR_STOP      stop batch execution after error\n"));
+	fprintf(output, _("  PORT               server port of the current connection\n"));
+	fprintf(output, _("  PROMPT1            specify standard the psql prompt\n"));
+	fprintf(output, _("  PROMPT2            specify the psql prompt when statement continues from previous line\n"));
+	fprintf(output, _("  PROMPT3            specify the psql prompt used by COPY statement\n"));
+	fprintf(output, _("  QUIET              run quietly (same as -q option)\n"));
+	fprintf(output, _("  SINGLELINE         end of line terminates SQL command mode (same as -S option)\n"));
+	fprintf(output, _("  SINGLESTEP         single-step mode (same as -s option)\n"));
+	fprintf(output, _("  USER               the currently connected database user\n"));
+	fprintf(output, _("  VERBOSITY          control verbosity of error reports [default, verbose, terse]\n"));
+
+	fprintf(output, _("\nPrinting options:\n"));
+	fprintf(output, _("Usage:\n"));
+	fprintf(output, _("  psql --pset=NAME[=VALUE]\n  or \\pset NAME [VALUE] in interactive mode\n\n"));
+
+	fprintf(output, _("  border             border style (number)\n"));
+	fprintf(output, _("  columns            set the target width for the wrapped format\n"));
+	fprintf(output, _("  expanded (or x)    toggle expanded output\n"));
+	fprintf(output, _("  fieldsep           field separator for unaligned output (default '|')\n"));
+	fprintf(output, _("  fieldsep_zero      set field separator in unaligned mode to zero\n"));
+	fprintf(output, _("  format             set output format [unaligned, aligned, wrapped, html, latex, ..]\n"));
+	fprintf(output, _("  footer             enable or disable display of the table footer [on, off]\n"));
+	fprintf(output, _("  linestyle          set the border line drawing style [ascii, old-ascii, unicode]\n"));
+	fprintf(output, _("  null               set the string to be printed in place of a null value\n"));
+	fprintf(output, _("  numericlocale      enable or disable display of a locale-specific character to separate\n"
+					 "                     groups of digits [on, off]\n"));
+	fprintf(output, _("  pager              control when an external pager is used [yes, no, always]\n"));
+	fprintf(output, _("  recordsep          specify the record (line) separator to use in unaligned output format\n"));
+	fprintf(output, _("  recordsep_zero     set the record separator to use in unaligned output format to a zero byte.\n"));
+	fprintf(output, _("  tableattr (or T)   specify attributes for table tag in html format or proportional\n"
+					 "                     column width of left aligned data type in latex format\n"));
+	fprintf(output, _("  title              set the table title for any subsequently printed tables\n"));
+	fprintf(output, _("  tuples_only        if set, only actual table data is shown\n"));
+
+	fprintf(output, _("\nEnvironment variables:\n"));
+	fprintf(output, _("Usage:\n"));
+
+#ifndef WIN32
+	fprintf(output, _("  NAME=VALUE [NAME=VALUE] psql ...\n  or \\setenv NAME [VALUE] in interactive mode\n\n"));
+#else
+	fprintf(output, _("  set NAME=VALUE\n  psql ...\n  or \\setenv NAME VALUE in interactive mode\n\n"));
+#endif
+
+	fprintf(output, _("  COLUMNS            number of columns for wrapped format\n"));
+	fprintf(output, _("  PAGER              name of external pager program\n"));
+	fprintf(output, _("  PGAPPNAME          same as the application_name connection parameter\n"));
+	fprintf(output, _("  PGDATABASE         same as the dbname connection parameter\n"));
+	fprintf(output, _("  PGHOST             same as the host connection parameter\n"));
+	fprintf(output, _("  PGPORT             same as the port connection parameter\n"));
+	fprintf(output, _("  PGUSER             same as the user connection parameter\n"));
+	fprintf(output, _("  PGPASSWORD         connection password (not recommended)\n"));
+	fprintf(output, _("  PGPASSFILE         password file name\n"));
+	fprintf(output, _("  PSQL_EDITOR, EDITOR, VISUAL\n"
+					 "                     editor used by the \\e and \\ef commands\n"));
+	fprintf(output, _("  PSQL_EDITOR_LINENUMBER_ARG\n"
+					 "                     how to specify a line number when invoking the editor\n"));
+	fprintf(output, _("  PSQL_HISTORY       alternative location for the command history file\n"));
+	fprintf(output, _("  PSQLRC             alternative location for the user's .psqlrc file\n"));
+	fprintf(output, _("  SHELL              shell used by the \\! command\n"));
+	fprintf(output, _("  TMPDIR             directory for temporary files\n"));
+
+	fprintf(output, _("\nFor more information consult the psql section in the PostgreSQL\n"
+			 "documentation.\n\n"));
+	fprintf(output, _("Report bugs to <pgsql-bugs@postgresql.org>.\n"));
+
+	ClosePager(output);
+}
+
 
 /*
  * helpSQL -- help with SQL commands
diff --git a/src/bin/psql/help.h b/src/bin/psql/help.h
index 054d5a4..bab360d 100644
--- a/src/bin/psql/help.h
+++ b/src/bin/psql/help.h
@@ -8,10 +8,12 @@
 #ifndef HELP_H
 #define HELP_H
 
-void		usage(void);
+void		usage(unsigned short int pager);
 
 void		slashUsage(unsigned short int pager);
 
+void		help_variables(unsigned short int pager);
+
 void		helpSQL(const char *topic, unsigned short int pager);
 
 void		print_copyright(void);
diff --git a/src/bin/psql/startup.c b/src/bin/psql/startup.c
index 5a397e8..af68e13 100644
--- a/src/bin/psql/startup.c
+++ b/src/bin/psql/startup.c
@@ -77,6 +77,8 @@ static void process_psqlrc_file(char *filename);
 static void showVersion(void);
 static void EstablishVariableSpace(void);
 
+#define NOPAGER		0
+
 /*
  *
  * main
@@ -97,7 +99,7 @@ main(int argc, char *argv[])
 	{
 		if (strcmp(argv[1], "--help") == 0 || strcmp(argv[1], "-?") == 0)
 		{
-			usage();
+			usage(NOPAGER);
 			exit(EXIT_SUCCESS);
 		}
 		if (strcmp(argv[1], "--version") == 0 || strcmp(argv[1], "-V") == 0)
@@ -384,6 +386,7 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 		{"expanded", no_argument, NULL, 'x'},
 		{"no-psqlrc", no_argument, NULL, 'X'},
 		{"help", no_argument, NULL, '?'},
+		{"help-variables", no_argument, NULL, 1},
 		{NULL, 0, NULL, 0}
 	};
 
@@ -559,7 +562,7 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 				/* Actual help option given */
 				if (strcmp(argv[optind - 1], "--help") == 0 || strcmp(argv[optind - 1], "-?") == 0)
 				{
-					usage();
+					usage(NOPAGER);
 					exit(EXIT_SUCCESS);
 				}
 				/* unknown option reported by getopt */
@@ -570,6 +573,9 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 					exit(EXIT_FAILURE);
 				}
 				break;
+			case 1:
+				help_variables(NOPAGER);
+				exit(EXIT_SUCCESS);
 			default:
 				fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
 						pset.progname);
diff --git a/src/bin/psql/tab-complete.c b/src/bin/psql/tab-complete.c
index 8288b41..ec6182b 100644
--- a/src/bin/psql/tab-complete.c
+++ b/src/bin/psql/tab-complete.c
@@ -3524,6 +3524,13 @@ psql_completion(const char *text, int start, int end)
 
 /* Backslash commands */
 /* TODO:  \dc \dd \dl */
+	else if (strcmp(prev_wd, "\\?") == 0)
+	{
+		static const char *const my_list[] =
+		{"options", "variables", NULL};
+
+		COMPLETE_WITH_LIST_CS(my_list);
+	}
 	else if (strcmp(prev_wd, "\\connect") == 0 || strcmp(prev_wd, "\\c") == 0)
 		COMPLETE_WITH_QUERY(Query_for_list_of_databases);
 

commit cac76b6135ae9f4b3c1eab1ce6bc34b43a7506ef
Author: Pavel Stehule <pavel.stehule@gooddata.com>
Date:   Wed Aug 27 22:47:07 2014 +0200

    access to help_variables and usage from psql via psql command

diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml
index db314c3..05a0f01 100644
--- a/doc/src/sgml/ref/psql-ref.sgml
+++ b/doc/src/sgml/ref/psql-ref.sgml
@@ -560,11 +560,18 @@ EOF
     <varlistentry>
       <term><option>-?</></term>
       <term><option>--help</></term>
+      <term><option>--help=<replaceable class="parameter">topic</replaceable></option></term>
       <listitem>
       <para>
       Show help about <application>psql</application> command line
       arguments, and exit.
       </para>
+
+      <para>
+      <option>--help=variables</>show help about <application>psql</application> variables,
+      and exit.
+      </para>
+
       </listitem>
     </varlistentry>
 
@@ -2572,10 +2579,12 @@ testdb=&gt; <userinput>\setenv LESS -imx4F</userinput>
 
 
       <varlistentry>
-        <term><literal>\?</literal></term>
+        <term><literal>\? [ options | variables ]</literal></term>
         <listitem>
         <para>
-        Shows help information about the backslash commands.
+        Shows help information about the backslash commands.  This command can have a
+        option "variables" or "options" to take help for psql configuration variables
+        or psql command line options.
         </para>
         </listitem>
       </varlistentry>
diff --git a/src/bin/psql/command.c b/src/bin/psql/command.c
index e16b4d5..987a79f 100644
--- a/src/bin/psql/command.c
+++ b/src/bin/psql/command.c
@@ -1503,7 +1503,19 @@ exec_command(const char *cmd,
 
 	/* \? -- slash command help */
 	else if (strcmp(cmd, "?") == 0)
-		slashUsage(pset.popt.topt.pager);
+	{
+		char	   *opt0 = psql_scan_slash_option(scan_state,
+													OT_NORMAL, NULL, false);
+
+		if (!opt0)
+			slashUsage(pset.popt.topt.pager);
+		else if (strcmp(opt0, "variables") == 0)
+			help_variables(pset.popt.topt.pager);
+		else if (strcmp(opt0, "options") == 0)
+			usage(pset.popt.topt.pager);
+		else
+			slashUsage(pset.popt.topt.pager);
+	}
 
 #if 0
 
diff --git a/src/bin/psql/help.c b/src/bin/psql/help.c
index f8f000f..0ada015 100644
--- a/src/bin/psql/help.c
+++ b/src/bin/psql/help.c
@@ -46,11 +46,12 @@
 #define ON(var) (var ? _("on") : _("off"))
 
 void
-usage(void)
+usage(unsigned short int pager)
 {
 	const char *env;
 	const char *user;
 	char	   *errstr;
+	FILE	   *output;
 
 	/* Find default user, in case we need it. */
 	user = getenv("PGUSER");
@@ -64,77 +65,82 @@ usage(void)
 		}
 	}
 
-	printf(_("psql is the PostgreSQL interactive terminal.\n\n"));
-	printf(_("Usage:\n"));
-	printf(_("  psql [OPTION]... [DBNAME [USERNAME]]\n\n"));
+	output = PageOutput(59, pager);
+
+	fprintf(output, _("psql is the PostgreSQL interactive terminal.\n\n"));
+	fprintf(output, _("Usage:\n"));
+	fprintf(output, _("  psql [OPTION]... [DBNAME [USERNAME]]\n\n"));
 
-	printf(_("General options:\n"));
+	fprintf(output, _("General options:\n"));
 	/* Display default database */
 	env = getenv("PGDATABASE");
 	if (!env)
 		env = user;
-	printf(_("  -c, --command=COMMAND    run only single command (SQL or internal) and exit\n"));
-	printf(_("  -d, --dbname=DBNAME      database name to connect to (default: \"%s\")\n"), env);
-	printf(_("  -f, --file=FILENAME      execute commands from file, then exit\n"));
-	printf(_("  -l, --list               list available databases, then exit\n"));
-	printf(_("  -v, --set=, --variable=NAME=VALUE\n"
-			 "                           set psql variable NAME to VALUE\n"));
-	printf(_("  -V, --version            output version information, then exit\n"));
-	printf(_("  -X, --no-psqlrc          do not read startup file (~/.psqlrc)\n"));
-	printf(_("  -1 (\"one\"), --single-transaction\n"
+	fprintf(output, _("  -c, --command=COMMAND    run only single command (SQL or internal) and exit\n"));
+	fprintf(output, _("  -d, --dbname=DBNAME      database name to connect to (default: \"%s\")\n"), env);
+	fprintf(output, _("  -f, --file=FILENAME      execute commands from file, then exit\n"));
+	fprintf(output, _("  -l, --list               list available databases, then exit\n"));
+	fprintf(output, _("  -v, --set=, --variable=NAME=VALUE\n"
+			 "                           set psql variable NAME to VALUE e.g.: -v ON_ERROR_STOP=1\n"));
+	fprintf(output, _("  -V, --version            output version information, then exit\n"));
+	fprintf(output, _("  -X, --no-psqlrc          do not read startup file (~/.psqlrc)\n"));
+	fprintf(output, _("  -1 (\"one\"), --single-transaction\n"
 			 "                           execute as a single transaction (if non-interactive)\n"));
-	printf(_("  -?, --help               show this help, then exit\n"));
-
-	printf(_("\nInput and output options:\n"));
-	printf(_("  -a, --echo-all           echo all input from script\n"));
-	printf(_("  -b, --echo-errors        echo failed commands\n"));
-	printf(_("  -e, --echo-queries       echo commands sent to server\n"));
-	printf(_("  -E, --echo-hidden        display queries that internal commands generate\n"));
-	printf(_("  -L, --log-file=FILENAME  send session log to file\n"));
-	printf(_("  -n, --no-readline        disable enhanced command line editing (readline)\n"));
-	printf(_("  -o, --output=FILENAME    send query results to file (or |pipe)\n"));
-	printf(_("  -q, --quiet              run quietly (no messages, only query output)\n"));
-	printf(_("  -s, --single-step        single-step mode (confirm each query)\n"));
-	printf(_("  -S, --single-line        single-line mode (end of line terminates SQL command)\n"));
-
-	printf(_("\nOutput format options:\n"));
-	printf(_("  -A, --no-align           unaligned table output mode\n"));
-	printf(_("  -F, --field-separator=STRING\n"
+	fprintf(output, _("  -?, --help               show this help, then exit\n"));
+	fprintf(output, _("  --help=variables         show a list of all specially treated variables, then exit\n"));
+
+	fprintf(output, _("\nInput and output options:\n"));
+	fprintf(output, _("  -a, --echo-all           echo all input from script\n"));
+	fprintf(output, _("  -b, --echo-errors        echo failed commands\n"));
+	fprintf(output, _("  -e, --echo-queries       echo commands sent to server\n"));
+	fprintf(output, _("  -E, --echo-hidden        display queries that internal commands generate\n"));
+	fprintf(output, _("  -L, --log-file=FILENAME  send session log to file\n"));
+	fprintf(output, _("  -n, --no-readline        disable enhanced command line editing (readline)\n"));
+	fprintf(output, _("  -o, --output=FILENAME    send query results to file (or |pipe)\n"));
+	fprintf(output, _("  -q, --quiet              run quietly (no messages, only query output)\n"));
+	fprintf(output, _("  -s, --single-step        single-step mode (confirm each query)\n"));
+	fprintf(output, _("  -S, --single-line        single-line mode (end of line terminates SQL command)\n"));
+
+	fprintf(output, _("\nOutput format options:\n"));
+	fprintf(output, _("  -A, --no-align           unaligned table output mode\n"));
+	fprintf(output, _("  -F, --field-separator=STRING\n"
 			 "                           field separator for unaligned output (default: \"%s\")\n"),
 		   DEFAULT_FIELD_SEP);
-	printf(_("  -H, --html               HTML table output mode\n"));
-	printf(_("  -P, --pset=VAR[=ARG]     set printing option VAR to ARG (see \\pset command)\n"));
-	printf(_("  -R, --record-separator=STRING\n"
+	fprintf(output, _("  -H, --html               HTML table output mode\n"));
+	fprintf(output, _("  -P, --pset=VAR[=ARG]     set printing option VAR to ARG (see \\pset command)\n"));
+	fprintf(output, _("  -R, --record-separator=STRING\n"
 			 "                           record separator for unaligned output (default: newline)\n"));
-	printf(_("  -t, --tuples-only        print rows only\n"));
-	printf(_("  -T, --table-attr=TEXT    set HTML table tag attributes (e.g., width, border)\n"));
-	printf(_("  -x, --expanded           turn on expanded table output\n"));
-	printf(_("  -z, --field-separator-zero\n"
+	fprintf(output, _("  -t, --tuples-only        print rows only\n"));
+	fprintf(output, _("  -T, --table-attr=TEXT    set HTML table tag attributes (e.g., width, border)\n"));
+	fprintf(output, _("  -x, --expanded           turn on expanded table output\n"));
+	fprintf(output, _("  -z, --field-separator-zero\n"
 			 "                           set field separator for unaligned output to zero byte\n"));
-	printf(_("  -0, --record-separator-zero\n"
+	fprintf(output, _("  -0, --record-separator-zero\n"
 			 "                           set record separator for unaligned output to zero byte\n"));
 
-	printf(_("\nConnection options:\n"));
+	fprintf(output, _("\nConnection options:\n"));
 	/* Display default host */
 	env = getenv("PGHOST");
-	printf(_("  -h, --host=HOSTNAME      database server host or socket directory (default: \"%s\")\n"),
+	fprintf(output, _("  -h, --host=HOSTNAME      database server host or socket directory (default: \"%s\")\n"),
 		   env ? env : _("local socket"));
 	/* Display default port */
 	env = getenv("PGPORT");
-	printf(_("  -p, --port=PORT          database server port (default: \"%s\")\n"),
+	fprintf(output, _("  -p, --port=PORT          database server port (default: \"%s\")\n"),
 		   env ? env : DEF_PGPORT_STR);
 	/* Display default user */
 	env = getenv("PGUSER");
 	if (!env)
 		env = user;
-	printf(_("  -U, --username=USERNAME  database user name (default: \"%s\")\n"), env);
-	printf(_("  -w, --no-password        never prompt for password\n"));
-	printf(_("  -W, --password           force password prompt (should happen automatically)\n"));
+	fprintf(output, _("  -U, --username=USERNAME  database user name (default: \"%s\")\n"), env);
+	fprintf(output, _("  -w, --no-password        never prompt for password\n"));
+	fprintf(output, _("  -W, --password           force password prompt (should happen automatically)\n"));
 
-	printf(_("\nFor more information, type \"\\?\" (for internal commands) or \"\\help\" (for SQL\n"
+	fprintf(output, _("\nFor more information, type \"\\?\" (for internal commands) or \"\\help\" (for SQL\n"
 			 "commands) from within psql, or consult the psql section in the PostgreSQL\n"
 			 "documentation.\n\n"));
-	printf(_("Report bugs to <pgsql-bugs@postgresql.org>.\n"));
+	fprintf(output, _("Report bugs to <pgsql-bugs@postgresql.org>.\n"));
+
+	ClosePager(output);
 }
 
 
@@ -159,11 +165,18 @@ slashUsage(unsigned short int pager)
 	fprintf(output, _("  \\copyright             show PostgreSQL usage and distribution terms\n"));
 	fprintf(output, _("  \\g [FILE] or ;         execute query (and send results to file or |pipe)\n"));
 	fprintf(output, _("  \\gset [PREFIX]         execute query and store results in psql variables\n"));
-	fprintf(output, _("  \\h [NAME]              help on syntax of SQL commands, * for all commands\n"));
 	fprintf(output, _("  \\q                     quit psql\n"));
 	fprintf(output, _("  \\watch [SEC]           execute query every SEC seconds\n"));
 	fprintf(output, "\n");
 
+	fprintf(output, _("Help\n"));
+
+	fprintf(output, _("  \\?                     description of all psql commands\n"));
+	fprintf(output, _("  \\? options             description of psql options\n"));
+	fprintf(output, _("  \\? variables           description of all psql configuration variables\n"));
+	fprintf(output, _("  \\h [NAME]              help on syntax of SQL commands, * for all commands\n"));
+	fprintf(output, "\n");
+
 	fprintf(output, _("Query Buffer\n"));
 	fprintf(output, _("  \\e [FILE] [LINE]       edit the query buffer (or file) with external editor\n"));
 	fprintf(output, _("  \\ef [FUNCNAME [LINE]]  edit function definition with external editor\n"));
@@ -280,6 +293,108 @@ slashUsage(unsigned short int pager)
 }
 
 
+/*
+ * show list of available variables (options) from command line
+ */
+void
+help_variables(unsigned short int pager)
+{
+	FILE	   *output;
+
+	output = PageOutput(86, pager);
+
+	fprintf(output, _("List of specially treated variables.\n"));
+
+	fprintf(output, _("psql variables:\n"));
+	fprintf(output, _("Usage:\n"));
+	fprintf(output, _("  psql --set=NAME=VALUE\n  or \\set NAME VALUE in interactive mode\n\n"));
+
+	fprintf(output, _("  AUTOCOMMIT         if set, successful SQL commands are automatically committed\n"));
+	fprintf(output, _("  COMP_KEYWORD_CASE  determine the case used to complete SQL keywords\n"
+					 "                     [lower, upper, preserve-lower, preserve-upper]\n"));
+	fprintf(output, _("  DBNAME             the currently connected database name\n"));
+	fprintf(output, _("  ECHO               control what input is written to standard output\n"
+					 "                     [all, errors, none, queries]\n"));
+	fprintf(output, _("  ECHO_HIDDEN        display internal queries executed by backslash commands when it is set\n"
+					 "                     or with [noexec] just show without execution\n"));
+	fprintf(output, _("  ENCODING           current client character set encoding\n"));
+	fprintf(output, _("  FETCH_COUNT        the number of result rows to fetch and display at a time\n"
+					 "                     (default: 0=unlimited)\n"));
+	fprintf(output, _("  HISTCONTROL        control history list [ignorespace, ignoredups, ignoreboth]\n"));
+	fprintf(output, _("  HISTFILE           file name used to store the history list\n"));
+	fprintf(output, _("  HISTSIZE           the number of commands to store in the command history\n"));
+	fprintf(output, _("  HOST               the currently connected database server\n"));
+	fprintf(output, _("  IGNOREEOF          if unset, sending an EOF to interactive session terminates application\n"));
+	fprintf(output, _("  LASTOID            the value of last affected OID\n"));
+	fprintf(output, _("  ON_ERROR_ROLLBACK  if set, an error doesn't stop a transaction (uses implicit SAVEPOINTs)\n"));
+	fprintf(output, _("  ON_ERROR_STOP      stop batch execution after error\n"));
+	fprintf(output, _("  PORT               server port of the current connection\n"));
+	fprintf(output, _("  PROMPT1            specify standard the psql prompt\n"));
+	fprintf(output, _("  PROMPT2            specify the psql prompt when statement continues from previous line\n"));
+	fprintf(output, _("  PROMPT3            specify the psql prompt used by COPY statement\n"));
+	fprintf(output, _("  QUIET              run quietly (same as -q option)\n"));
+	fprintf(output, _("  SINGLELINE         end of line terminates SQL command mode (same as -S option)\n"));
+	fprintf(output, _("  SINGLESTEP         single-step mode (same as -s option)\n"));
+	fprintf(output, _("  USER               the currently connected database user\n"));
+	fprintf(output, _("  VERBOSITY          control verbosity of error reports [default, verbose, terse]\n"));
+
+	fprintf(output, _("\nPrinting options:\n"));
+	fprintf(output, _("Usage:\n"));
+	fprintf(output, _("  psql --pset=NAME[=VALUE]\n  or \\pset NAME [VALUE] in interactive mode\n\n"));
+
+	fprintf(output, _("  border             border style (number)\n"));
+	fprintf(output, _("  columns            set the target width for the wrapped format\n"));
+	fprintf(output, _("  expanded (or x)    toggle expanded output\n"));
+	fprintf(output, _("  fieldsep           field separator for unaligned output (default '|')\n"));
+	fprintf(output, _("  fieldsep_zero      set field separator in unaligned mode to zero\n"));
+	fprintf(output, _("  format             set output format [unaligned, aligned, wrapped, html, latex, ..]\n"));
+	fprintf(output, _("  footer             enable or disable display of the table footer [on, off]\n"));
+	fprintf(output, _("  linestyle          set the border line drawing style [ascii, old-ascii, unicode]\n"));
+	fprintf(output, _("  null               set the string to be printed in place of a null value\n"));
+	fprintf(output, _("  numericlocale      enable or disable display of a locale-specific character to separate\n"
+					 "                     groups of digits [on, off]\n"));
+	fprintf(output, _("  pager              control when an external pager is used [yes, no, always]\n"));
+	fprintf(output, _("  recordsep          specify the record (line) separator to use in unaligned output format\n"));
+	fprintf(output, _("  recordsep_zero     set the record separator to use in unaligned output format to a zero byte.\n"));
+	fprintf(output, _("  tableattr (or T)   specify attributes for table tag in html format or proportional\n"
+					 "                     column width of left aligned data type in latex format\n"));
+	fprintf(output, _("  title              set the table title for any subsequently printed tables\n"));
+	fprintf(output, _("  tuples_only        if set, only actual table data is shown\n"));
+
+	fprintf(output, _("\nEnvironment variables:\n"));
+	fprintf(output, _("Usage:\n"));
+
+#ifndef WIN32
+	fprintf(output, _("  NAME=VALUE [NAME=VALUE] psql ...\n  or \\setenv NAME [VALUE] in interactive mode\n\n"));
+#else
+	fprintf(output, _("  set NAME=VALUE\n  psql ...\n  or \\setenv NAME VALUE in interactive mode\n\n"));
+#endif
+
+	fprintf(output, _("  COLUMNS            number of columns for wrapped format\n"));
+	fprintf(output, _("  PAGER              name of external pager program\n"));
+	fprintf(output, _("  PGAPPNAME          same as the application_name connection parameter\n"));
+	fprintf(output, _("  PGDATABASE         same as the dbname connection parameter\n"));
+	fprintf(output, _("  PGHOST             same as the host connection parameter\n"));
+	fprintf(output, _("  PGPORT             same as the port connection parameter\n"));
+	fprintf(output, _("  PGUSER             same as the user connection parameter\n"));
+	fprintf(output, _("  PGPASSWORD         connection password (not recommended)\n"));
+	fprintf(output, _("  PGPASSFILE         password file name\n"));
+	fprintf(output, _("  PSQL_EDITOR, EDITOR, VISUAL\n"
+					 "                     editor used by the \\e and \\ef commands\n"));
+	fprintf(output, _("  PSQL_EDITOR_LINENUMBER_ARG\n"
+					 "                     how to specify a line number when invoking the editor\n"));
+	fprintf(output, _("  PSQL_HISTORY       alternative location for the command history file\n"));
+	fprintf(output, _("  PSQLRC             alternative location for the user's .psqlrc file\n"));
+	fprintf(output, _("  SHELL              shell used by the \\! command\n"));
+	fprintf(output, _("  TMPDIR             directory for temporary files\n"));
+
+	fprintf(output, _("\nFor more information consult the psql section in the PostgreSQL\n"
+			 "documentation.\n\n"));
+	fprintf(output, _("Report bugs to <pgsql-bugs@postgresql.org>.\n"));
+
+	ClosePager(output);
+}
+
 
 /*
  * helpSQL -- help with SQL commands
diff --git a/src/bin/psql/help.h b/src/bin/psql/help.h
index 054d5a4..bab360d 100644
--- a/src/bin/psql/help.h
+++ b/src/bin/psql/help.h
@@ -8,10 +8,12 @@
 #ifndef HELP_H
 #define HELP_H
 
-void		usage(void);
+void		usage(unsigned short int pager);
 
 void		slashUsage(unsigned short int pager);
 
+void		help_variables(unsigned short int pager);
+
 void		helpSQL(const char *topic, unsigned short int pager);
 
 void		print_copyright(void);
diff --git a/src/bin/psql/startup.c b/src/bin/psql/startup.c
index 5a397e8..dd051e6 100644
--- a/src/bin/psql/startup.c
+++ b/src/bin/psql/startup.c
@@ -77,6 +77,8 @@ static void process_psqlrc_file(char *filename);
 static void showVersion(void);
 static void EstablishVariableSpace(void);
 
+#define NOPAGER		0
+
 /*
  *
  * main
@@ -95,9 +97,9 @@ main(int argc, char *argv[])
 
 	if (argc > 1)
 	{
-		if (strcmp(argv[1], "--help") == 0 || strcmp(argv[1], "-?") == 0)
+		if ((strcmp(argv[1], "-?") == 0) || (argc == 2 && (strcmp(argv[1], "--help") == 0)))
 		{
-			usage();
+			usage(NOPAGER);
 			exit(EXIT_SUCCESS);
 		}
 		if (strcmp(argv[1], "--version") == 0 || strcmp(argv[1], "-V") == 0)
@@ -383,7 +385,7 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 		{"password", no_argument, NULL, 'W'},
 		{"expanded", no_argument, NULL, 'x'},
 		{"no-psqlrc", no_argument, NULL, 'X'},
-		{"help", no_argument, NULL, '?'},
+		{"help", optional_argument, NULL, 1},
 		{NULL, 0, NULL, 0}
 	};
 
@@ -392,7 +394,7 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 
 	memset(options, 0, sizeof *options);
 
-	while ((c = getopt_long(argc, argv, "aAbc:d:eEf:F:h:HlL:no:p:P:qR:sStT:U:v:VwWxXz?01",
+	while ((c = getopt_long(argc, argv, "aAbc:d:eEf:F:h:HlL:no:p:P:qR:sStT:U:v:VwWxXz?0",
 							long_options, &optindex)) != -1)
 	{
 		switch (c)
@@ -556,13 +558,11 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 				options->single_txn = true;
 				break;
 			case '?':
-				/* Actual help option given */
-				if (strcmp(argv[optind - 1], "--help") == 0 || strcmp(argv[optind - 1], "-?") == 0)
+				if (strcmp(argv[optind - 1], "-?") == 0)
 				{
-					usage();
+					usage(NOPAGER);
 					exit(EXIT_SUCCESS);
 				}
-				/* unknown option reported by getopt */
 				else
 				{
 					fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
@@ -570,6 +570,16 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 					exit(EXIT_FAILURE);
 				}
 				break;
+			case 1:
+				{
+					if (optarg && strcmp(optarg, "variables") == 0)
+						help_variables(NOPAGER);
+					else
+						usage(NOPAGER);
+
+					exit(EXIT_SUCCESS);
+				}
+				break;
 			default:
 				fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
 						pset.progname);
diff --git a/src/bin/psql/tab-complete.c b/src/bin/psql/tab-complete.c
index 8288b41..ec6182b 100644
--- a/src/bin/psql/tab-complete.c
+++ b/src/bin/psql/tab-complete.c
@@ -3524,6 +3524,13 @@ psql_completion(const char *text, int start, int end)
 
 /* Backslash commands */
 /* TODO:  \dc \dd \dl */
+	else if (strcmp(prev_wd, "\\?") == 0)
+	{
+		static const char *const my_list[] =
+		{"options", "variables", NULL};
+
+		COMPLETE_WITH_LIST_CS(my_list);
+	}
 	else if (strcmp(prev_wd, "\\connect") == 0 || strcmp(prev_wd, "\\c") == 0)
 		COMPLETE_WITH_QUERY(Query_for_list_of_databases);
 

>From 9fcf3f0983ccd617c20dc4e87889a894d873b92e Mon Sep 17 00:00:00 2001
From: Andres Freund <andres@anarazel.de>
Date: Tue, 9 Sep 2014 22:19:14 +0200
Subject: [PATCH] Add new psql help topics, accessible to both --help and \?.

Add --help=<topic> for the commandline, and \? <topic> as a backslash
command, to show more help than the invocations without parameters
do. "commands", "variables" and "options" currently exist as help
topics describing, respectively, backslash commands, psql variables,
and commandline switches. Without parameters the help commands show
their previous topic.

Author: Pavel Stehule, editorialized by many

Reviewed-By: Andres Freund, Petr Jelinek, Fujii Masao, MauMau, Abhijit
    Menon-Sen and Erik Rijkers.

Discussion: CAFj8pRDVGuC-nXBfe2CK8vpyzd2Dsr9GVpbrATAnZO=2YQ0s2Q@mail.gmail.com,
    CAFj8pRA54AbTv2RXDTRxiAd8hy8wxmoVLqhJDRCwEnhdd7OUkw@mail.gmail.com
---
 doc/src/sgml/ref/psql-ref.sgml |  23 ++++-
 src/bin/psql/command.c         |  14 ++-
 src/bin/psql/help.c            | 210 +++++++++++++++++++++++++++++++----------
 src/bin/psql/help.h            |   4 +-
 src/bin/psql/startup.c         |  29 ++++--
 src/bin/psql/tab-complete.c    |   7 ++
 6 files changed, 224 insertions(+), 63 deletions(-)

diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml
index 29ad1aa..aa71674 100644
--- a/doc/src/sgml/ref/psql-ref.sgml
+++ b/doc/src/sgml/ref/psql-ref.sgml
@@ -560,11 +560,17 @@ EOF
 
     <varlistentry>
       <term><option>-?</></term>
-      <term><option>--help</></term>
+      <term><option>--help[=<replaceable class="parameter">topic</>]</option></term>
       <listitem>
       <para>
-      Show help about <application>psql</application> command line
-      arguments, and exit.
+      Show help about <application>psql</application> and exit. The optional
+      <replaceable class="parameter">topic</> parameter (defaulting
+      to <literal>options</literal>) selects which part of psql is
+      explained: <literal>commands</> describes <application>psql</>'s
+      backslash commands; <literal>options</> describes the commandline
+      switches that can be passed to <application>psql</>;
+      and <literal>variables</> shows help about about psql configuration
+      variables.
       </para>
       </listitem>
     </varlistentry>
@@ -2574,10 +2580,17 @@ testdb=&gt; <userinput>\setenv LESS -imx4F</userinput>
 
 
       <varlistentry>
-        <term><literal>\?</literal></term>
+        <term><literal>\? [ <replaceable class="parameter">topic</> ]</literal></term>
         <listitem>
         <para>
-        Shows help information about the backslash commands.
+        Shows help information. The optional
+        <replaceable class="parameter">topic</> parameter
+        (defaulting to <literal>commands</>) selects which part of psql is
+        explained: <literal>commands</> describes <application>psql</>'s
+        backslash commands; <literal>options</> describes the commandline
+        switches that can be passed to <application>psql</>;
+        and <literal>variables</> shows help about about psql configuration
+        variables.
         </para>
         </listitem>
       </varlistentry>
diff --git a/src/bin/psql/command.c b/src/bin/psql/command.c
index 39b5777..5d90ca2 100644
--- a/src/bin/psql/command.c
+++ b/src/bin/psql/command.c
@@ -1491,7 +1491,19 @@ exec_command(const char *cmd,
 
 	/* \? -- slash command help */
 	else if (strcmp(cmd, "?") == 0)
-		slashUsage(pset.popt.topt.pager);
+	{
+		char	   *opt0 = psql_scan_slash_option(scan_state,
+													OT_NORMAL, NULL, false);
+
+		if (!opt0 || strcmp(opt0, "commands") == 0)
+			slashUsage(pset.popt.topt.pager);
+		else if (strcmp(opt0, "options") == 0)
+			usage(pset.popt.topt.pager);
+		else if (strcmp(opt0, "variables") == 0)
+			helpVariables(pset.popt.topt.pager);
+		else
+			slashUsage(pset.popt.topt.pager);
+	}
 
 #if 0
 
diff --git a/src/bin/psql/help.c b/src/bin/psql/help.c
index f8f000f..ef35696 100644
--- a/src/bin/psql/help.c
+++ b/src/bin/psql/help.c
@@ -46,11 +46,12 @@
 #define ON(var) (var ? _("on") : _("off"))
 
 void
-usage(void)
+usage(unsigned short int pager)
 {
 	const char *env;
 	const char *user;
 	char	   *errstr;
+	FILE	   *output;
 
 	/* Find default user, in case we need it. */
 	user = getenv("PGUSER");
@@ -64,77 +65,83 @@ usage(void)
 		}
 	}
 
-	printf(_("psql is the PostgreSQL interactive terminal.\n\n"));
-	printf(_("Usage:\n"));
-	printf(_("  psql [OPTION]... [DBNAME [USERNAME]]\n\n"));
+	output = PageOutput(59, pager);
+
+	fprintf(output, _("psql is the PostgreSQL interactive terminal.\n\n"));
+	fprintf(output, _("Usage:\n"));
+	fprintf(output, _("  psql [OPTION]... [DBNAME [USERNAME]]\n\n"));
 
-	printf(_("General options:\n"));
+	fprintf(output, _("General options:\n"));
 	/* Display default database */
 	env = getenv("PGDATABASE");
 	if (!env)
 		env = user;
-	printf(_("  -c, --command=COMMAND    run only single command (SQL or internal) and exit\n"));
-	printf(_("  -d, --dbname=DBNAME      database name to connect to (default: \"%s\")\n"), env);
-	printf(_("  -f, --file=FILENAME      execute commands from file, then exit\n"));
-	printf(_("  -l, --list               list available databases, then exit\n"));
-	printf(_("  -v, --set=, --variable=NAME=VALUE\n"
-			 "                           set psql variable NAME to VALUE\n"));
-	printf(_("  -V, --version            output version information, then exit\n"));
-	printf(_("  -X, --no-psqlrc          do not read startup file (~/.psqlrc)\n"));
-	printf(_("  -1 (\"one\"), --single-transaction\n"
+	fprintf(output, _("  -c, --command=COMMAND    run only single command (SQL or internal) and exit\n"));
+	fprintf(output, _("  -d, --dbname=DBNAME      database name to connect to (default: \"%s\")\n"), env);
+	fprintf(output, _("  -f, --file=FILENAME      execute commands from file, then exit\n"));
+	fprintf(output, _("  -l, --list               list available databases, then exit\n"));
+	fprintf(output, _("  -v, --set=, --variable=NAME=VALUE\n"
+			 "                           set psql variable NAME to VALUE e.g.: -v ON_ERROR_STOP=1\n"));
+	fprintf(output, _("  -V, --version            output version information, then exit\n"));
+	fprintf(output, _("  -X, --no-psqlrc          do not read startup file (~/.psqlrc)\n"));
+	fprintf(output, _("  -1 (\"one\"), --single-transaction\n"
 			 "                           execute as a single transaction (if non-interactive)\n"));
-	printf(_("  -?, --help               show this help, then exit\n"));
-
-	printf(_("\nInput and output options:\n"));
-	printf(_("  -a, --echo-all           echo all input from script\n"));
-	printf(_("  -b, --echo-errors        echo failed commands\n"));
-	printf(_("  -e, --echo-queries       echo commands sent to server\n"));
-	printf(_("  -E, --echo-hidden        display queries that internal commands generate\n"));
-	printf(_("  -L, --log-file=FILENAME  send session log to file\n"));
-	printf(_("  -n, --no-readline        disable enhanced command line editing (readline)\n"));
-	printf(_("  -o, --output=FILENAME    send query results to file (or |pipe)\n"));
-	printf(_("  -q, --quiet              run quietly (no messages, only query output)\n"));
-	printf(_("  -s, --single-step        single-step mode (confirm each query)\n"));
-	printf(_("  -S, --single-line        single-line mode (end of line terminates SQL command)\n"));
-
-	printf(_("\nOutput format options:\n"));
-	printf(_("  -A, --no-align           unaligned table output mode\n"));
-	printf(_("  -F, --field-separator=STRING\n"
+	fprintf(output, _("  -?, --help[=options]     show this help, then exit\n"));
+	fprintf(output, _("      --help=variables     show a list of all specially treated variables, then exit\n"));
+	fprintf(output, _("      --help=commands      show a list of backslash commands, then exit\n"));
+
+	fprintf(output, _("\nInput and output options:\n"));
+	fprintf(output, _("  -a, --echo-all           echo all input from script\n"));
+	fprintf(output, _("  -b, --echo-errors        echo failed commands\n"));
+	fprintf(output, _("  -e, --echo-queries       echo commands sent to server\n"));
+	fprintf(output, _("  -E, --echo-hidden        display queries that internal commands generate\n"));
+	fprintf(output, _("  -L, --log-file=FILENAME  send session log to file\n"));
+	fprintf(output, _("  -n, --no-readline        disable enhanced command line editing (readline)\n"));
+	fprintf(output, _("  -o, --output=FILENAME    send query results to file (or |pipe)\n"));
+	fprintf(output, _("  -q, --quiet              run quietly (no messages, only query output)\n"));
+	fprintf(output, _("  -s, --single-step        single-step mode (confirm each query)\n"));
+	fprintf(output, _("  -S, --single-line        single-line mode (end of line terminates SQL command)\n"));
+
+	fprintf(output, _("\nOutput format options:\n"));
+	fprintf(output, _("  -A, --no-align           unaligned table output mode\n"));
+	fprintf(output, _("  -F, --field-separator=STRING\n"
 			 "                           field separator for unaligned output (default: \"%s\")\n"),
 		   DEFAULT_FIELD_SEP);
-	printf(_("  -H, --html               HTML table output mode\n"));
-	printf(_("  -P, --pset=VAR[=ARG]     set printing option VAR to ARG (see \\pset command)\n"));
-	printf(_("  -R, --record-separator=STRING\n"
+	fprintf(output, _("  -H, --html               HTML table output mode\n"));
+	fprintf(output, _("  -P, --pset=VAR[=ARG]     set printing option VAR to ARG (see \\pset command)\n"));
+	fprintf(output, _("  -R, --record-separator=STRING\n"
 			 "                           record separator for unaligned output (default: newline)\n"));
-	printf(_("  -t, --tuples-only        print rows only\n"));
-	printf(_("  -T, --table-attr=TEXT    set HTML table tag attributes (e.g., width, border)\n"));
-	printf(_("  -x, --expanded           turn on expanded table output\n"));
-	printf(_("  -z, --field-separator-zero\n"
+	fprintf(output, _("  -t, --tuples-only        print rows only\n"));
+	fprintf(output, _("  -T, --table-attr=TEXT    set HTML table tag attributes (e.g., width, border)\n"));
+	fprintf(output, _("  -x, --expanded           turn on expanded table output\n"));
+	fprintf(output, _("  -z, --field-separator-zero\n"
 			 "                           set field separator for unaligned output to zero byte\n"));
-	printf(_("  -0, --record-separator-zero\n"
+	fprintf(output, _("  -0, --record-separator-zero\n"
 			 "                           set record separator for unaligned output to zero byte\n"));
 
-	printf(_("\nConnection options:\n"));
+	fprintf(output, _("\nConnection options:\n"));
 	/* Display default host */
 	env = getenv("PGHOST");
-	printf(_("  -h, --host=HOSTNAME      database server host or socket directory (default: \"%s\")\n"),
+	fprintf(output, _("  -h, --host=HOSTNAME      database server host or socket directory (default: \"%s\")\n"),
 		   env ? env : _("local socket"));
 	/* Display default port */
 	env = getenv("PGPORT");
-	printf(_("  -p, --port=PORT          database server port (default: \"%s\")\n"),
+	fprintf(output, _("  -p, --port=PORT          database server port (default: \"%s\")\n"),
 		   env ? env : DEF_PGPORT_STR);
 	/* Display default user */
 	env = getenv("PGUSER");
 	if (!env)
 		env = user;
-	printf(_("  -U, --username=USERNAME  database user name (default: \"%s\")\n"), env);
-	printf(_("  -w, --no-password        never prompt for password\n"));
-	printf(_("  -W, --password           force password prompt (should happen automatically)\n"));
+	fprintf(output, _("  -U, --username=USERNAME  database user name (default: \"%s\")\n"), env);
+	fprintf(output, _("  -w, --no-password        never prompt for password\n"));
+	fprintf(output, _("  -W, --password           force password prompt (should happen automatically)\n"));
 
-	printf(_("\nFor more information, type \"\\?\" (for internal commands) or \"\\help\" (for SQL\n"
+	fprintf(output, _("\nFor more information, type \"\\?\" (for internal commands) or \"\\help\" (for SQL\n"
 			 "commands) from within psql, or consult the psql section in the PostgreSQL\n"
 			 "documentation.\n\n"));
-	printf(_("Report bugs to <pgsql-bugs@postgresql.org>.\n"));
+	fprintf(output, _("Report bugs to <pgsql-bugs@postgresql.org>.\n"));
+
+	ClosePager(output);
 }
 
 
@@ -159,11 +166,18 @@ slashUsage(unsigned short int pager)
 	fprintf(output, _("  \\copyright             show PostgreSQL usage and distribution terms\n"));
 	fprintf(output, _("  \\g [FILE] or ;         execute query (and send results to file or |pipe)\n"));
 	fprintf(output, _("  \\gset [PREFIX]         execute query and store results in psql variables\n"));
-	fprintf(output, _("  \\h [NAME]              help on syntax of SQL commands, * for all commands\n"));
 	fprintf(output, _("  \\q                     quit psql\n"));
 	fprintf(output, _("  \\watch [SEC]           execute query every SEC seconds\n"));
 	fprintf(output, "\n");
 
+	fprintf(output, _("Help\n"));
+
+	fprintf(output, _("  \\? [commands]          description of all psql backslash commands\n"));
+	fprintf(output, _("  \\? options             description of all psql commandline options\n"));
+	fprintf(output, _("  \\? variables           description of all psql configuration variables\n"));
+	fprintf(output, _("  \\h [NAME]              help on syntax of SQL commands, * for all commands\n"));
+	fprintf(output, "\n");
+
 	fprintf(output, _("Query Buffer\n"));
 	fprintf(output, _("  \\e [FILE] [LINE]       edit the query buffer (or file) with external editor\n"));
 	fprintf(output, _("  \\ef [FUNCNAME [LINE]]  edit function definition with external editor\n"));
@@ -280,6 +294,106 @@ slashUsage(unsigned short int pager)
 }
 
 
+/*
+ * helpVariables
+ *
+ * show list of available variables (options) from command line
+ */
+void
+helpVariables(unsigned short int pager)
+{
+	FILE	   *output;
+
+	output = PageOutput(81, pager);
+
+	fprintf(output, _("List of specially treated variables.\n"));
+
+	fprintf(output, _("psql variables:\n"));
+	fprintf(output, _("Usage:\n"));
+	fprintf(output, _("  psql --set=NAME=VALUE\n  or \\set NAME VALUE in interactive mode\n\n"));
+
+	fprintf(output, _("  AUTOCOMMIT         if set, successful SQL commands are automatically committed\n"));
+	fprintf(output, _("  COMP_KEYWORD_CASE  determine the case used to complete SQL keywords\n"
+					 "                     [lower, upper, preserve-lower, preserve-upper]\n"));
+	fprintf(output, _("  DBNAME             the currently connected database name\n"));
+	fprintf(output, _("  ECHO               control what input is written to standard output\n"
+					 "                     [all, errors, none, queries]\n"));
+	fprintf(output, _("  ECHO_HIDDEN        display internal queries executed by backslash commands when it is set\n"
+					 "                     or with [noexec] just show without execution\n"));
+	fprintf(output, _("  ENCODING           current client character set encoding\n"));
+	fprintf(output, _("  FETCH_COUNT        the number of result rows to fetch and display at a time\n"
+					 "                     (default: 0=unlimited)\n"));
+	fprintf(output, _("  HISTCONTROL        control history list [ignorespace, ignoredups, ignoreboth]\n"));
+	fprintf(output, _("  HISTFILE           file name used to store the history list\n"));
+	fprintf(output, _("  HISTSIZE           the number of commands to store in the command history\n"));
+	fprintf(output, _("  HOST               the currently connected database server\n"));
+	fprintf(output, _("  IGNOREEOF          if unset, sending an EOF to interactive session terminates application\n"));
+	fprintf(output, _("  LASTOID            the value of last affected OID\n"));
+	fprintf(output, _("  ON_ERROR_ROLLBACK  if set, an error doesn't stop a transaction (uses implicit SAVEPOINTs)\n"));
+	fprintf(output, _("  ON_ERROR_STOP      stop batch execution after error\n"));
+	fprintf(output, _("  PORT               server port of the current connection\n"));
+	fprintf(output, _("  PROMPT1            specify the standard psql prompt\n"));
+	fprintf(output, _("  PROMPT2            specify the prompt used when a statement continues from a previous line\n"));
+	fprintf(output, _("  PROMPT3            specify the prompt used during COPY ... FROM STDIN\n"));
+	fprintf(output, _("  QUIET              run quietly (same as -q option)\n"));
+	fprintf(output, _("  SINGLELINE         end of line terminates SQL command mode (same as -S option)\n"));
+	fprintf(output, _("  SINGLESTEP         single-step mode (same as -s option)\n"));
+	fprintf(output, _("  USER               the currently connected database user\n"));
+	fprintf(output, _("  VERBOSITY          control verbosity of error reports [default, verbose, terse]\n"));
+
+	fprintf(output, _("\nDisplay influencing variables:\n"));
+	fprintf(output, _("Usage:\n"));
+	fprintf(output, _("  psql --pset=NAME[=VALUE]\n  or \\pset NAME [VALUE] in interactive mode\n\n"));
+
+	fprintf(output, _("  border             border style (number)\n"));
+	fprintf(output, _("  columns            set the target width for the wrapped format\n"));
+	fprintf(output, _("  expanded (or x)    toggle expanded output\n"));
+	fprintf(output, _("  fieldsep           field separator for unaligned output (default '|')\n"));
+	fprintf(output, _("  fieldsep_zero      set field separator in unaligned mode to zero\n"));
+	fprintf(output, _("  format             set output format [unaligned, aligned, wrapped, html, latex, ..]\n"));
+	fprintf(output, _("  footer             enable or disable display of the table footer [on, off]\n"));
+	fprintf(output, _("  linestyle          set the border line drawing style [ascii, old-ascii, unicode]\n"));
+	fprintf(output, _("  null               set the string to be printed in place of a null value\n"));
+	fprintf(output, _("  numericlocale      enable or disable display of a locale-specific character to separate\n"
+					 "                     groups of digits [on, off]\n"));
+	fprintf(output, _("  pager              control when an external pager is used [yes, no, always]\n"));
+	fprintf(output, _("  recordsep          specify the record (line) separator to use in unaligned output format\n"));
+	fprintf(output, _("  recordsep_zero     set the record separator to use in unaligned output format to a zero byte.\n"));
+	fprintf(output, _("  tableattr (or T)   specify attributes for table tag in html format or proportional\n"
+					 "                     column width of left aligned data type in latex format\n"));
+	fprintf(output, _("  title              set the table title for any subsequently printed tables\n"));
+	fprintf(output, _("  tuples_only        if set, only actual table data is shown\n"));
+
+	fprintf(output, _("\nEnvironment variables:\n"));
+	fprintf(output, _("Usage:\n"));
+
+#ifndef WIN32
+	fprintf(output, _("  NAME=VALUE [NAME=VALUE] psql ...\n  or \\setenv NAME [VALUE] in interactive mode\n\n"));
+#else
+	fprintf(output, _("  set NAME=VALUE\n  psql ...\n  or \\setenv NAME VALUE in interactive mode\n\n"));
+#endif
+
+	fprintf(output, _("  COLUMNS            number of columns for wrapped format\n"));
+	fprintf(output, _("  PAGER              name of external pager program\n"));
+	fprintf(output, _("  PGAPPNAME          same as the application_name connection parameter\n"));
+	fprintf(output, _("  PGDATABASE         same as the dbname connection parameter\n"));
+	fprintf(output, _("  PGHOST             same as the host connection parameter\n"));
+	fprintf(output, _("  PGPORT             same as the port connection parameter\n"));
+	fprintf(output, _("  PGUSER             same as the user connection parameter\n"));
+	fprintf(output, _("  PGPASSWORD         connection password (not recommended)\n"));
+	fprintf(output, _("  PGPASSFILE         password file name\n"));
+	fprintf(output, _("  PSQL_EDITOR, EDITOR, VISUAL\n"
+					 "                     editor used by the \\e and \\ef commands\n"));
+	fprintf(output, _("  PSQL_EDITOR_LINENUMBER_ARG\n"
+					 "                     how to specify a line number when invoking the editor\n"));
+	fprintf(output, _("  PSQL_HISTORY       alternative location for the command history file\n"));
+	fprintf(output, _("  PSQLRC             alternative location for the user's .psqlrc file\n"));
+	fprintf(output, _("  SHELL              shell used by the \\! command\n"));
+	fprintf(output, _("  TMPDIR             directory for temporary files\n"));
+
+	ClosePager(output);
+}
+
 
 /*
  * helpSQL -- help with SQL commands
diff --git a/src/bin/psql/help.h b/src/bin/psql/help.h
index 054d5a4..3ad374a 100644
--- a/src/bin/psql/help.h
+++ b/src/bin/psql/help.h
@@ -8,10 +8,12 @@
 #ifndef HELP_H
 #define HELP_H
 
-void		usage(void);
+void		usage(unsigned short int pager);
 
 void		slashUsage(unsigned short int pager);
 
+void		helpVariables(unsigned short int pager);
+
 void		helpSQL(const char *topic, unsigned short int pager);
 
 void		print_copyright(void);
diff --git a/src/bin/psql/startup.c b/src/bin/psql/startup.c
index 5a397e8..b879d0c 100644
--- a/src/bin/psql/startup.c
+++ b/src/bin/psql/startup.c
@@ -77,6 +77,8 @@ static void process_psqlrc_file(char *filename);
 static void showVersion(void);
 static void EstablishVariableSpace(void);
 
+#define NOPAGER		0
+
 /*
  *
  * main
@@ -95,9 +97,9 @@ main(int argc, char *argv[])
 
 	if (argc > 1)
 	{
-		if (strcmp(argv[1], "--help") == 0 || strcmp(argv[1], "-?") == 0)
+		if ((strcmp(argv[1], "-?") == 0) || (argc == 2 && (strcmp(argv[1], "--help") == 0)))
 		{
-			usage();
+			usage(NOPAGER);
 			exit(EXIT_SUCCESS);
 		}
 		if (strcmp(argv[1], "--version") == 0 || strcmp(argv[1], "-V") == 0)
@@ -383,7 +385,7 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 		{"password", no_argument, NULL, 'W'},
 		{"expanded", no_argument, NULL, 'x'},
 		{"no-psqlrc", no_argument, NULL, 'X'},
-		{"help", no_argument, NULL, '?'},
+		{"help", optional_argument, NULL, 1},
 		{NULL, 0, NULL, 0}
 	};
 
@@ -557,20 +559,31 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 				break;
 			case '?':
 				/* Actual help option given */
-				if (strcmp(argv[optind - 1], "--help") == 0 || strcmp(argv[optind - 1], "-?") == 0)
+				if (strcmp(argv[optind - 1], "-?") == 0)
 				{
-					usage();
+					usage(NOPAGER);
 					exit(EXIT_SUCCESS);
 				}
 				/* unknown option reported by getopt */
 				else
+					goto unknown_option;
+				break;
+			case 1:
 				{
-					fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
-							pset.progname);
-					exit(EXIT_FAILURE);
+					if (!optarg || strcmp(optarg, "options") == 0)
+						usage(NOPAGER);
+					else if (optarg && strcmp(optarg, "commands") == 0)
+						slashUsage(NOPAGER);
+					else if (optarg && strcmp(optarg, "variables") == 0)
+						helpVariables(NOPAGER);
+					else
+						goto unknown_option;
+
+					exit(EXIT_SUCCESS);
 				}
 				break;
 			default:
+			unknown_option:
 				fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
 						pset.progname);
 				exit(EXIT_FAILURE);
diff --git a/src/bin/psql/tab-complete.c b/src/bin/psql/tab-complete.c
index 7577c4b..4ce47e9 100644
--- a/src/bin/psql/tab-complete.c
+++ b/src/bin/psql/tab-complete.c
@@ -3543,6 +3543,13 @@ psql_completion(const char *text, int start, int end)
 
 /* Backslash commands */
 /* TODO:  \dc \dd \dl */
+	else if (strcmp(prev_wd, "\\?") == 0)
+	{
+		static const char *const my_list[] =
+		{"commands", "options", "variables", NULL};
+
+		COMPLETE_WITH_LIST_CS(my_list);
+	}
 	else if (strcmp(prev_wd, "\\connect") == 0 || strcmp(prev_wd, "\\c") == 0)
 		COMPLETE_WITH_QUERY(Query_for_list_of_databases);
 
-- 
2.0.0.rc2.4.g1dc51c6.dirty

diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml
index c5b091c..aa71674 100644
--- a/doc/src/sgml/ref/psql-ref.sgml
+++ b/doc/src/sgml/ref/psql-ref.sgml
@@ -560,19 +560,18 @@ EOF
 
     <varlistentry>
       <term><option>-?</></term>
-      <term><option>--help</></term>
-      <term><option>--help=<replaceable class="parameter">topic</replaceable></option></term>
+      <term><option>--help[=<replaceable class="parameter">topic</>]</option></term>
       <listitem>
       <para>
-      Show help about <application>psql</application> command line
-      arguments, and exit.
+      Show help about <application>psql</application> and exit. The optional
+      <replaceable class="parameter">topic</> parameter (defaulting
+      to <literal>options</literal>) selects which part of psql is
+      explained: <literal>commands</> describes <application>psql</>'s
+      backslash commands; <literal>options</> describes the commandline
+      switches that can be passed to <application>psql</>;
+      and <literal>variables</> shows help about about psql configuration
+      variables.
       </para>
-
-      <para>
-      <option>--help=variables</>show help about <application>psql</application> variables,
-      and exit.
-      </para>
-
       </listitem>
     </varlistentry>
 
@@ -2581,12 +2580,17 @@ testdb=&gt; <userinput>\setenv LESS -imx4F</userinput>
 
 
       <varlistentry>
-        <term><literal>\? [ options | variables ]</literal></term>
+        <term><literal>\? [ <replaceable class="parameter">topic</> ]</literal></term>
         <listitem>
         <para>
-        Shows help information about the backslash commands.  This command can have a
-        option "variables" or "options" to take help for psql configuration variables
-        or psql command line options.
+        Shows help information. The optional
+        <replaceable class="parameter">topic</> parameter
+        (defaulting to <literal>commands</>) selects which part of psql is
+        explained: <literal>commands</> describes <application>psql</>'s
+        backslash commands; <literal>options</> describes the commandline
+        switches that can be passed to <application>psql</>;
+        and <literal>variables</> shows help about about psql configuration
+        variables.
         </para>
         </listitem>
       </varlistentry>
diff --git a/src/bin/psql/command.c b/src/bin/psql/command.c
index c7140b8..5d90ca2 100644
--- a/src/bin/psql/command.c
+++ b/src/bin/psql/command.c
@@ -1495,12 +1495,12 @@ exec_command(const char *cmd,
 		char	   *opt0 = psql_scan_slash_option(scan_state,
 													OT_NORMAL, NULL, false);
 
-		if (!opt0)
+		if (!opt0 || strcmp(opt0, "commands") == 0)
 			slashUsage(pset.popt.topt.pager);
-		else if (strcmp(opt0, "variables") == 0)
-			help_variables(pset.popt.topt.pager);
 		else if (strcmp(opt0, "options") == 0)
 			usage(pset.popt.topt.pager);
+		else if (strcmp(opt0, "variables") == 0)
+			helpVariables(pset.popt.topt.pager);
 		else
 			slashUsage(pset.popt.topt.pager);
 	}
diff --git a/src/bin/psql/help.c b/src/bin/psql/help.c
index 0ada015..ef35696 100644
--- a/src/bin/psql/help.c
+++ b/src/bin/psql/help.c
@@ -86,8 +86,9 @@ usage(unsigned short int pager)
 	fprintf(output, _("  -X, --no-psqlrc          do not read startup file (~/.psqlrc)\n"));
 	fprintf(output, _("  -1 (\"one\"), --single-transaction\n"
 			 "                           execute as a single transaction (if non-interactive)\n"));
-	fprintf(output, _("  -?, --help               show this help, then exit\n"));
-	fprintf(output, _("  --help=variables         show a list of all specially treated variables, then exit\n"));
+	fprintf(output, _("  -?, --help[=options]     show this help, then exit\n"));
+	fprintf(output, _("      --help=variables     show a list of all specially treated variables, then exit\n"));
+	fprintf(output, _("      --help=commands      show a list of backslash commands, then exit\n"));
 
 	fprintf(output, _("\nInput and output options:\n"));
 	fprintf(output, _("  -a, --echo-all           echo all input from script\n"));
@@ -171,8 +172,8 @@ slashUsage(unsigned short int pager)
 
 	fprintf(output, _("Help\n"));
 
-	fprintf(output, _("  \\?                     description of all psql commands\n"));
-	fprintf(output, _("  \\? options             description of psql options\n"));
+	fprintf(output, _("  \\? [commands]          description of all psql backslash commands\n"));
+	fprintf(output, _("  \\? options             description of all psql commandline options\n"));
 	fprintf(output, _("  \\? variables           description of all psql configuration variables\n"));
 	fprintf(output, _("  \\h [NAME]              help on syntax of SQL commands, * for all commands\n"));
 	fprintf(output, "\n");
@@ -294,14 +295,16 @@ slashUsage(unsigned short int pager)
 
 
 /*
+ * helpVariables
+ *
  * show list of available variables (options) from command line
  */
 void
-help_variables(unsigned short int pager)
+helpVariables(unsigned short int pager)
 {
 	FILE	   *output;
 
-	output = PageOutput(86, pager);
+	output = PageOutput(81, pager);
 
 	fprintf(output, _("List of specially treated variables.\n"));
 
@@ -329,16 +332,16 @@ help_variables(unsigned short int pager)
 	fprintf(output, _("  ON_ERROR_ROLLBACK  if set, an error doesn't stop a transaction (uses implicit SAVEPOINTs)\n"));
 	fprintf(output, _("  ON_ERROR_STOP      stop batch execution after error\n"));
 	fprintf(output, _("  PORT               server port of the current connection\n"));
-	fprintf(output, _("  PROMPT1            specify standard the psql prompt\n"));
-	fprintf(output, _("  PROMPT2            specify the psql prompt when statement continues from previous line\n"));
-	fprintf(output, _("  PROMPT3            specify the psql prompt used by COPY statement\n"));
+	fprintf(output, _("  PROMPT1            specify the standard psql prompt\n"));
+	fprintf(output, _("  PROMPT2            specify the prompt used when a statement continues from a previous line\n"));
+	fprintf(output, _("  PROMPT3            specify the prompt used during COPY ... FROM STDIN\n"));
 	fprintf(output, _("  QUIET              run quietly (same as -q option)\n"));
 	fprintf(output, _("  SINGLELINE         end of line terminates SQL command mode (same as -S option)\n"));
 	fprintf(output, _("  SINGLESTEP         single-step mode (same as -s option)\n"));
 	fprintf(output, _("  USER               the currently connected database user\n"));
 	fprintf(output, _("  VERBOSITY          control verbosity of error reports [default, verbose, terse]\n"));
 
-	fprintf(output, _("\nPrinting options:\n"));
+	fprintf(output, _("\nDisplay influencing variables:\n"));
 	fprintf(output, _("Usage:\n"));
 	fprintf(output, _("  psql --pset=NAME[=VALUE]\n  or \\pset NAME [VALUE] in interactive mode\n\n"));
 
@@ -388,10 +391,6 @@ help_variables(unsigned short int pager)
 	fprintf(output, _("  SHELL              shell used by the \\! command\n"));
 	fprintf(output, _("  TMPDIR             directory for temporary files\n"));
 
-	fprintf(output, _("\nFor more information consult the psql section in the PostgreSQL\n"
-			 "documentation.\n\n"));
-	fprintf(output, _("Report bugs to <pgsql-bugs@postgresql.org>.\n"));
-
 	ClosePager(output);
 }
 
diff --git a/src/bin/psql/help.h b/src/bin/psql/help.h
index bab360d..3ad374a 100644
--- a/src/bin/psql/help.h
+++ b/src/bin/psql/help.h
@@ -12,7 +12,7 @@ void		usage(unsigned short int pager);
 
 void		slashUsage(unsigned short int pager);
 
-void		help_variables(unsigned short int pager);
+void		helpVariables(unsigned short int pager);
 
 void		helpSQL(const char *topic, unsigned short int pager);
 
diff --git a/src/bin/psql/startup.c b/src/bin/psql/startup.c
index dd051e6..b879d0c 100644
--- a/src/bin/psql/startup.c
+++ b/src/bin/psql/startup.c
@@ -394,7 +394,7 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 
 	memset(options, 0, sizeof *options);
 
-	while ((c = getopt_long(argc, argv, "aAbc:d:eEf:F:h:HlL:no:p:P:qR:sStT:U:v:VwWxXz?0",
+	while ((c = getopt_long(argc, argv, "aAbc:d:eEf:F:h:HlL:no:p:P:qR:sStT:U:v:VwWxXz?01",
 							long_options, &optindex)) != -1)
 	{
 		switch (c)
@@ -558,29 +558,32 @@ parse_psql_options(int argc, char *argv[], struct adhoc_opts * options)
 				options->single_txn = true;
 				break;
 			case '?':
+				/* Actual help option given */
 				if (strcmp(argv[optind - 1], "-?") == 0)
 				{
 					usage(NOPAGER);
 					exit(EXIT_SUCCESS);
 				}
+				/* unknown option reported by getopt */
 				else
-				{
-					fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
-							pset.progname);
-					exit(EXIT_FAILURE);
-				}
+					goto unknown_option;
 				break;
 			case 1:
 				{
-					if (optarg && strcmp(optarg, "variables") == 0)
-						help_variables(NOPAGER);
-					else
+					if (!optarg || strcmp(optarg, "options") == 0)
 						usage(NOPAGER);
+					else if (optarg && strcmp(optarg, "commands") == 0)
+						slashUsage(NOPAGER);
+					else if (optarg && strcmp(optarg, "variables") == 0)
+						helpVariables(NOPAGER);
+					else
+						goto unknown_option;
 
 					exit(EXIT_SUCCESS);
 				}
 				break;
 			default:
+			unknown_option:
 				fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
 						pset.progname);
 				exit(EXIT_FAILURE);
diff --git a/src/bin/psql/tab-complete.c b/src/bin/psql/tab-complete.c
index 012f8c5..4ce47e9 100644
--- a/src/bin/psql/tab-complete.c
+++ b/src/bin/psql/tab-complete.c
@@ -3546,7 +3546,7 @@ psql_completion(const char *text, int start, int end)
 	else if (strcmp(prev_wd, "\\?") == 0)
 	{
 		static const char *const my_list[] =
-		{"options", "variables", NULL};
+		{"commands", "options", "variables", NULL};
 
 		COMPLETE_WITH_LIST_CS(my_list);
 	}