Ability to listen on two unix sockets

diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c
index dd7dd55..a4745cc 100644
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -156,9 +156,16 @@ static Backend *ShmemBackendArray;
 
 /* The socket number we are listening for connections on */
 int			PostPortNumber;
+
+/* UNIX socket directory */
 char	   *UnixSocketDir;
+
+/* Addresses to bind to, for port number above */
 char	   *ListenAddresses;
 
+/* Additional sockets */
+char	   *additional_sockets;
+
 /*
  * ReservedBackends is the number of backends reserved for superuser use.
  * This number is taken out of the pool size given by MaxBackends so
@@ -896,6 +903,86 @@ PostmasterMain(int argc, char *argv[])
 		pfree(rawstring);
 	}
 
+	if (additional_sockets)
+	{
+		char	   *rawstring;
+		List	   *elemlist;
+		ListCell   *l;
+
+		/* Need a modifiable copy of additional_sockets */
+		rawstring = pstrdup(additional_sockets);
+
+		/* Parse string into list of identifiers */
+		if (!SplitIdentifierString(rawstring, ',', &elemlist))
+		{
+			/* syntax error in list */
+			ereport(FATAL,
+					(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+					 errmsg("invalid list syntax for \"additional_sockets\"")));
+		}
+
+		foreach(l, elemlist)
+		{
+			char	   *cursocket = (char *) lfirst(l);
+			char	   *colon;
+			char	   *host;
+			char	   *port;
+			int64		portnum;
+			char	   *endptr;
+			bool		bad_strtol;
+
+			/* syntax is port or host:port */
+			colon = strchr(cursocket, ':');
+			if (colon != NULL)
+			{
+				host = cursocket;
+				port = colon + 1;
+				*colon = '\0';
+			}
+			else
+			{
+				host = NULL;
+				port = cursocket;
+			}
+
+			/*
+			 * convert port number to integer, ignoring optional trailing
+			 * whitespace).  strtol should ignore leading whitespace, too.
+			 */
+			portnum = strtol(port, &endptr, 0);
+			bad_strtol = (errno == ERANGE);
+			while (isspace((unsigned char) *endptr))
+				endptr++;
+			if (*endptr != '\0')
+				ereport(FATAL,
+						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+						 errmsg("port number \"%s\" invalid in \"additional_sockets\"", port)));
+			if (bad_strtol || portnum < 1 || portnum > 65535)
+				ereport(FATAL,
+						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+						 errmsg("port number \"%s\" out of range in \"additional_sockets\"", port)));
+
+
+			status = StreamServerPort(AF_UNSPEC, host,
+									  (unsigned short) portnum,
+									  UnixSocketDir,
+									  ListenSocket, MAXLISTEN);
+
+			if (status != STATUS_OK)
+			{
+				/* put the colon back, for error-reporting purposes */
+				if (colon != NULL)
+					*colon = ':';
+				ereport(WARNING,
+						(errmsg("could not create additional socket for \"%s\"",
+								cursocket)));
+			}
+		}
+
+		list_free(elemlist);
+		pfree(rawstring);
+	}
+
 #ifdef USE_BONJOUR
 	/* Register for Bonjour only if we opened TCP socket(s) */
 	if (enable_bonjour && ListenSocket[0] != PGINVALID_SOCKET)
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index d75ab43..2429011 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -2650,6 +2650,16 @@ static struct config_string ConfigureNamesString[] =
 		NULL, NULL, NULL
 	},
 
+	{
+		{"additional_sockets", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
+			gettext_noop("Listen on additional sockets."),
+			NULL
+		},
+		&additional_sockets,
+		"",
+		NULL, NULL, NULL
+	},
+
 	/* See main.c about why defaults for LC_foo are not all alike */
 
 	{
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index fa75d00..ce1c385 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -61,6 +61,8 @@
 					# defaults to 'localhost'; use '*' for all
 					# (change requires restart)
 #port = 5432				# (change requires restart)
+#additional_sockets = ''	# comma-separated list of [host:]port
+					# (change requires restart)
 #max_connections = 100			# (change requires restart)
 # Note:  Increasing max_connections costs ~400 bytes of shared memory per
 # connection slot, plus lock space (see max_locks_per_transaction).
diff --git a/src/include/postmaster/postmaster.h b/src/include/postmaster/postmaster.h
index dded0e6..3d9ea41 100644
--- a/src/include/postmaster/postmaster.h
+++ b/src/include/postmaster/postmaster.h
@@ -17,6 +17,7 @@
 extern bool EnableSSL;
 extern int	ReservedBackends;
 extern int	PostPortNumber;
+extern char *additional_sockets;
 extern int	Unix_socket_permissions;
 extern char *Unix_socket_group;
 extern char *UnixSocketDir;

diff --git a/doc/src/sgml/client-auth.sgml b/doc/src/sgml/client-auth.sgml
index cfdb33a..679c40a 100644
--- a/doc/src/sgml/client-auth.sgml
+++ b/doc/src/sgml/client-auth.sgml
@@ -838,7 +838,7 @@ omicron         bryanh                  guest1
     <varname>unix_socket_permissions</varname> (and possibly
     <varname>unix_socket_group</varname>) configuration parameters as
     described in <xref linkend="runtime-config-connection">.  Or you
-    could set the <varname>unix_socket_directory</varname>
+    could set the <varname>unix_socket_directories</varname>
     configuration parameter to place the socket file in a suitably
     restricted directory.
    </para>
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 074afee..7634682 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -453,17 +453,23 @@ SET ENABLE_SEQSCAN TO OFF;
       </listitem>
      </varlistentry>
 
-     <varlistentry id="guc-unix-socket-directory" xreflabel="unix_socket_directory">
-      <term><varname>unix_socket_directory</varname> (<type>string</type>)</term>
+     <varlistentry id="guc-unix-socket-directories" xreflabel="unix_socket_directories">
+      <term><varname>unix_socket_directories</varname> (<type>string</type>)</term>
       <indexterm>
-       <primary><varname>unix_socket_directory</> configuration parameter</primary>
+       <primary><varname>unix_socket_directories</> configuration parameter</primary>
       </indexterm>
       <listitem>
        <para>
-        Specifies the directory of the Unix-domain socket on which the
+        Specifies the directories of the Unix-domain sockets on which the
         server is to listen for
         connections from client applications.  The default is normally
         <filename>/tmp</filename>, but can be changed at build time.
+        Directories are separated by ',' and additional <replaceable>port</> 
+        number can be set, separated from directory by ':'. Port number will 
+        only be used as a part of the socket file name. For example,
+        <literal>'/var/run, /tmp:5431'</literal> would create socket files
+        <literal>/var/run/.s.PGSQL.5432</literal> and
+        <literal>/tmp/.s.PGSQL.5431</literal>.
         This parameter can only be set at server start.
        </para>
 
@@ -472,7 +478,7 @@ SET ENABLE_SEQSCAN TO OFF;
         <literal>.s.PGSQL.<replaceable>nnnn</></literal> where
         <replaceable>nnnn</> is the server's port number, an ordinary file
         named <literal>.s.PGSQL.<replaceable>nnnn</>.lock</literal> will be
-        created in the <varname>unix_socket_directory</> directory.  Neither
+        created in the <varname>unix_socket_directories</> directories.  Neither
         file should ever be removed manually.
        </para>
 
@@ -6593,7 +6599,7 @@ LOG:  CleanUpLock: deleting: lock(0xb7acd844) id(24688,24696,0,0,0,1)
        </row>
        <row>
         <entry><option>-k <replaceable>x</replaceable></option></entry>
-        <entry><literal>unix_socket_directory = <replaceable>x</replaceable></></entry>
+        <entry><literal>unix_socket_directories = <replaceable>x</replaceable></></entry>
        </row>
        <row>
         <entry><option>-l</option></entry>
diff --git a/doc/src/sgml/runtime.sgml b/doc/src/sgml/runtime.sgml
index 7ba18f0..6c74844 100644
--- a/doc/src/sgml/runtime.sgml
+++ b/doc/src/sgml/runtime.sgml
@@ -1784,7 +1784,7 @@ pg_dumpall -p 5432 | psql -d postgres -p 5433
   <para>
    The simplest way to prevent spoofing for <literal>local</>
    connections is to use a Unix domain socket directory (<xref
-   linkend="guc-unix-socket-directory">) that has write permission only
+   linkend="guc-unix-socket-directories">) that has write permission only
    for a trusted local user.  This prevents a malicious user from creating
    their own socket file in that directory.  If you are concerned that
    some applications might still reference <filename>/tmp</> for the
diff --git a/src/backend/bootstrap/bootstrap.c b/src/backend/bootstrap/bootstrap.c
index e3ae92d..72505e3 100644
--- a/src/backend/bootstrap/bootstrap.c
+++ b/src/backend/bootstrap/bootstrap.c
@@ -349,7 +349,7 @@ AuxiliaryProcessMain(int argc, char *argv[])
 
 	/* If standalone, create lockfile for data directory */
 	if (!IsUnderPostmaster)
-		CreateDataDirLockFile(false);
+		CreateDataDirLockFile(false, NULL);
 
 	SetProcessingMode(BootstrapProcessing);
 	IgnoreSystemIndexes = true;
diff --git a/src/backend/libpq/pqcomm.c b/src/backend/libpq/pqcomm.c
index 5272811..cf1e157 100644
--- a/src/backend/libpq/pqcomm.c
+++ b/src/backend/libpq/pqcomm.c
@@ -103,8 +103,8 @@ int			Unix_socket_permissions;
 char	   *Unix_socket_group;
 
 
-/* Where the Unix socket file is */
-static char sock_path[MAXPGPATH];
+/* Where the Unix socket files are */
+static List *sock_paths = NIL;
 
 
 /*
@@ -140,8 +140,8 @@ static int	internal_flush(void);
 static void pq_set_nonblocking(bool nonblocking);
 
 #ifdef HAVE_UNIX_SOCKETS
-static int	Lock_AF_UNIX(unsigned short portNumber, char *unixSocketName);
-static int	Setup_AF_UNIX(void);
+static int	Lock_AF_UNIX(unsigned short portNumber, char *unixSocketName, char **sock_path);
+static int	Setup_AF_UNIX(char *sock_path);
 #endif   /* HAVE_UNIX_SOCKETS */
 
 
@@ -234,14 +234,23 @@ pq_close(int code, Datum arg)
 
 /* StreamDoUnlink()
  * Shutdown routine for backend connection
- * If a Unix socket is used for communication, explicitly close it.
+ * If any Unix sockets are used for communication, explicitly close them.
  */
 #ifdef HAVE_UNIX_SOCKETS
 static void
 StreamDoUnlink(int code, Datum arg)
 {
-	Assert(sock_path[0]);
-	unlink(sock_path);
+	ListCell	*l;
+	char	*cursocket;
+	
+	/* Loop through all created sockets... */
+	foreach(l, sock_paths)
+	{
+		cursocket = (char *) lfirst(l);
+		unlink(cursocket);
+	}
+	list_free(sock_paths);
+	sock_paths = NIL;
 }
 #endif   /* HAVE_UNIX_SOCKETS */
 
@@ -286,10 +295,9 @@ StreamServerPort(int family, char *hostName, unsigned short portNumber,
 #ifdef HAVE_UNIX_SOCKETS
 	if (family == AF_UNIX)
 	{
-		/* Lock_AF_UNIX will also fill in sock_path. */
-		if (Lock_AF_UNIX(portNumber, unixSocketName) != STATUS_OK)
+		/* Lock_AF_UNIX will also fill in service. */
+		if (Lock_AF_UNIX(portNumber, unixSocketName, &service) != STATUS_OK)
 			return STATUS_ERROR;
-		service = sock_path;
 	}
 	else
 #endif   /* HAVE_UNIX_SOCKETS */
@@ -432,7 +440,7 @@ StreamServerPort(int family, char *hostName, unsigned short portNumber,
 					 (IS_AF_UNIX(addr->ai_family)) ?
 				  errhint("Is another postmaster already running on port %d?"
 						  " If not, remove socket file \"%s\" and retry.",
-						  (int) portNumber, sock_path) :
+						  (int) portNumber, service) :
 				  errhint("Is another postmaster already running on port %d?"
 						  " If not, wait a few seconds and retry.",
 						  (int) portNumber)));
@@ -443,7 +451,7 @@ StreamServerPort(int family, char *hostName, unsigned short portNumber,
 #ifdef HAVE_UNIX_SOCKETS
 		if (addr->ai_family == AF_UNIX)
 		{
-			if (Setup_AF_UNIX() != STATUS_OK)
+			if (Setup_AF_UNIX(service) != STATUS_OK)
 			{
 				closesocket(fd);
 				break;
@@ -490,9 +498,13 @@ StreamServerPort(int family, char *hostName, unsigned short portNumber,
  * Lock_AF_UNIX -- configure unix socket file path
  */
 static int
-Lock_AF_UNIX(unsigned short portNumber, char *unixSocketName)
+Lock_AF_UNIX(unsigned short portNumber, char *unixSocketName, char **sock_path)
 {
-	UNIXSOCK_PATH(sock_path, portNumber, unixSocketName);
+	char new_sock[MAXPGPATH];
+
+	UNIXSOCK_PATH(new_sock, portNumber, unixSocketName);
+
+	*sock_path = pstrdup(new_sock);
 
 	/*
 	 * Grab an interlock file associated with the socket file.
@@ -502,13 +514,14 @@ Lock_AF_UNIX(unsigned short portNumber, char *unixSocketName)
 	 * more portable, and second, it lets us remove any pre-existing socket
 	 * file without race conditions.
 	 */
-	CreateSocketLockFile(sock_path, true);
+	CreateSocketLockFile(*sock_path, true, unixSocketName);
 
 	/*
 	 * Once we have the interlock, we can safely delete any pre-existing
 	 * socket file to avoid failure at bind() time.
 	 */
-	unlink(sock_path);
+	unlink(*sock_path);
+	sock_paths = lappend(sock_paths, *sock_path);
 
 	return STATUS_OK;
 }
@@ -518,7 +531,7 @@ Lock_AF_UNIX(unsigned short portNumber, char *unixSocketName)
  * Setup_AF_UNIX -- configure unix socket permissions
  */
 static int
-Setup_AF_UNIX(void)
+Setup_AF_UNIX(char *sock_path)
 {
 	/* Arrange to unlink the socket file at exit */
 	on_proc_exit(StreamDoUnlink, 0);
@@ -707,17 +720,21 @@ StreamClose(pgsocket sock)
  * TouchSocketFile -- mark socket file as recently accessed
  *
  * This routine should be called every so often to ensure that the socket
- * file has a recent mod date (ordinary operations on sockets usually won't
- * change the mod date).  That saves it from being removed by
+ * files have a recent mod date (ordinary operations on sockets usually won't
+ * change the mod date).  That saves them from being removed by
  * overenthusiastic /tmp-directory-cleaner daemons.  (Another reason we should
- * never have put the socket file in /tmp...)
+ * never have put the socket files in /tmp...)
  */
 void
 TouchSocketFile(void)
 {
-	/* Do nothing if we did not create a socket... */
-	if (sock_path[0] != '\0')
+	ListCell	*l;
+	char	*cursocket;
+	
+	/* Loop through all created sockets... */
+	foreach(l, sock_paths)
 	{
+		cursocket = (char *) lfirst(l);
 		/*
 		 * utime() is POSIX standard, utimes() is a common alternative. If we
 		 * have neither, there's no way to affect the mod or access time of
@@ -726,10 +743,10 @@ TouchSocketFile(void)
 		 * In either path, we ignore errors; there's no point in complaining.
 		 */
 #ifdef HAVE_UTIME
-		utime(sock_path, NULL);
+		utime(cursocket, NULL);
 #else							/* !HAVE_UTIME */
 #ifdef HAVE_UTIMES
-		utimes(sock_path, NULL);
+		utimes(cursocket, NULL);
 #endif   /* HAVE_UTIMES */
 #endif   /* HAVE_UTIME */
 	}
diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c
index eeea933..f91dcdd 100644
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -156,7 +156,7 @@ static Backend *ShmemBackendArray;
 
 /* The socket number we are listening for connections on */
 int			PostPortNumber;
-char	   *UnixSocketDir;
+char	   *UnixSocketDirs;
 char	   *ListenAddresses;
 
 /*
@@ -499,6 +499,10 @@ PostmasterMain(int argc, char *argv[])
 	char	   *userDoption = NULL;
 	bool		listen_addr_saved = false;
 	int			i;
+#ifdef HAVE_UNIX_SOCKETS
+	List	   *socketsList;
+	char	   *mainSocket = NULL;
+#endif
 
 	MyProcPid = PostmasterPid = getpid();
 
@@ -607,7 +611,7 @@ PostmasterMain(int argc, char *argv[])
 				break;
 
 			case 'k':
-				SetConfigOption("unix_socket_directory", optarg, PGC_POSTMASTER, PGC_S_ARGV);
+				SetConfigOption("unix_socket_directories", optarg, PGC_POSTMASTER, PGC_S_ARGV);
 				break;
 
 			case 'l':
@@ -807,6 +811,40 @@ PostmasterMain(int argc, char *argv[])
 	}
 
 	/*
+	 * We need to parse UnixSocketDirs here, because we want only 
+	 * the first socket directory be used in postmaster.pid, which is done
+	 * in CreateDataDirLockFile(). 
+	 */
+#ifdef HAVE_UNIX_SOCKETS
+	if (UnixSocketDirs)
+	{
+		char	   *rawSocketsString;
+		ListCell   *l;
+
+		/* Need a modifiable copy of UnixSocketDirs */
+		rawSocketsString = pstrdup(UnixSocketDirs);
+
+		/* Parse string into list of directories */
+		if (!SplitDirectoriesString(rawSocketsString, ',', &socketsList))
+		{
+			/* syntax error in list */
+			ereport(FATAL,
+				   (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							errmsg("invalid list syntax for \"unix_socket_directories\"")));
+		}
+
+		pfree(rawSocketsString);
+
+		if (l = list_head(socketsList))
+			mainSocket = (char *) lfirst(l);
+		else
+			mainSocket = UnixSocketDirs;
+	}
+	else
+		mainSocket = UnixSocketDirs;
+#endif
+
+	/*
 	 * Create lockfile for data directory.
 	 *
 	 * We want to do this before we try to grab the input sockets, because the
@@ -815,7 +853,7 @@ PostmasterMain(int argc, char *argv[])
 	 * For the same reason, it's best to grab the TCP socket(s) before the
 	 * Unix socket.
 	 */
-	CreateDataDirLockFile(true);
+	CreateDataDirLockFile(true, mainSocket);
 
 	/*
 	 * Initialize SSL library, if specified.
@@ -862,12 +900,12 @@ PostmasterMain(int argc, char *argv[])
 			if (strcmp(curhost, "*") == 0)
 				status = StreamServerPort(AF_UNSPEC, NULL,
 										  (unsigned short) PostPortNumber,
-										  UnixSocketDir,
+										  UnixSocketDirs,
 										  ListenSocket, MAXLISTEN);
 			else
 				status = StreamServerPort(AF_UNSPEC, curhost,
 										  (unsigned short) PostPortNumber,
-										  UnixSocketDir,
+										  UnixSocketDirs,
 										  ListenSocket, MAXLISTEN);
 
 			if (status == STATUS_OK)
@@ -933,13 +971,89 @@ PostmasterMain(int argc, char *argv[])
 #endif
 
 #ifdef HAVE_UNIX_SOCKETS
-	status = StreamServerPort(AF_UNIX, NULL,
-							  (unsigned short) PostPortNumber,
-							  UnixSocketDir,
-							  ListenSocket, MAXLISTEN);
-	if (status != STATUS_OK)
-		ereport(WARNING,
-				(errmsg("could not create Unix-domain socket")));
+	/* 
+	 * We can specify several directories for Unix sockets to listen on,
+	 * separated with ','. Socket name itself is the same in all cases.
+	 */
+	if (!UnixSocketDirs)
+	{
+		status = StreamServerPort(AF_UNIX, NULL,
+								  (unsigned short) PostPortNumber,
+								  UnixSocketDirs,
+								  ListenSocket, MAXLISTEN);
+		if (status != STATUS_OK)
+			ereport(WARNING,
+					(errmsg("could not create Unix-domain socket")));
+	
+	}
+	else
+	{
+		ListCell   *l;
+
+		/* We have parse string into list of directories earlier */
+		foreach(l, socketsList)
+		{
+			char	*cursocket = (char *) lfirst(l);
+			char	*colon;
+			char	*port;
+			int64	portnum;
+			char	*endptr;
+			bool	bad_strtol;
+			
+			/* syntax is directory or directory:port */
+			colon = strrchr(cursocket, ':');
+			if (colon != NULL)
+			{
+				port = colon + 1;
+				*colon = '\0';
+				
+				/*
+				 * convert port number to integer, ignoring optional trailing
+				 * whitespace).  strtol should ignore leading whitespace, too.
+				 */
+				portnum = strtol(port, &endptr, 0);
+				bad_strtol = (errno == ERANGE);
+
+				while (isspace((unsigned char) *endptr))
+					endptr++;
+
+				if (*endptr != '\0')
+				ereport(FATAL,
+						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+						 errmsg("port number \"%s\" invalid in \"unix_socket_directories\"", port)));
+
+				if (bad_strtol || portnum < 1 || portnum > 65535)
+					ereport(FATAL,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("port number \"%s\" out of range in \"unix_socket_directories\"", port)));
+			}
+			else
+			{
+				portnum = PostPortNumber;
+			}
+
+			/* only absolute paths are allowed */
+			canonicalize_path(cursocket);
+			if (!is_absolute_path(cursocket))
+			{
+				ereport(FATAL,
+						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+						 errmsg("directory \"%s\" is not an absolute path", cursocket)));
+			}
+			else
+			{
+				status = StreamServerPort(AF_UNIX, NULL,
+					(unsigned short) portnum,
+					cursocket,
+					ListenSocket, MAXLISTEN);
+				if (status != STATUS_OK)
+				ereport(FATAL,
+					(errmsg("could not create secondary Unix-domain socket at \"%s\"", cursocket)));
+			}
+		}
+		
+		list_free(socketsList);
+	}
 #endif
 
 	/*
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 51b6df5..837d0e8 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -3343,7 +3343,7 @@ process_postgres_switches(int argc, char *argv[], GucContext ctx)
 				break;
 
 			case 'k':
-				SetConfigOption("unix_socket_directory", optarg, ctx, gucsource);
+				SetConfigOption("unix_socket_directories", optarg, ctx, gucsource);
 				break;
 
 			case 'l':
@@ -3660,7 +3660,7 @@ PostgresMain(int argc, char *argv[], const char *username)
 		/*
 		 * Create lockfile for data directory.
 		 */
-		CreateDataDirLockFile(false);
+		CreateDataDirLockFile(false, NULL);
 	}
 
 	/* Early initialization */
diff --git a/src/backend/utils/adt/varlena.c b/src/backend/utils/adt/varlena.c
index e1b57ba..ffc7e2b 100644
--- a/src/backend/utils/adt/varlena.c
+++ b/src/backend/utils/adt/varlena.c
@@ -2445,6 +2445,107 @@ SplitIdentifierString(char *rawstring, char separator,
 	return true;
 }
 
+/*
+ * SplitDirectoriesString --- parse a string containing directories
+ *
+ * Inputs:
+ *	rawstring: the input string; must be overwritable!	On return, it's
+ *			   been modified to contain the separated directories.
+ *	separator: the separator punctuation expected between directories
+ *			   (typically ',' or ';').	Whitespace may also appear around
+ *			   directories.
+ * Outputs:
+ *	namelist: filled with a palloc'd list of pointers to directories within
+ *			  rawstring.  Caller should list_free() this even on error return.
+ *
+ * Returns TRUE if okay, FALSE if there is a syntax error in the string.
+ *
+ * Note that an empty string is considered okay here.
+ */
+bool
+SplitDirectoriesString(char *rawstring, char separator,
+					  List **namelist)
+{
+	char	   *nextp = rawstring;
+	bool		done = false;
+
+	*namelist = NIL;
+
+	while (isspace((unsigned char) *nextp))
+		nextp++;				/* skip leading whitespace */
+
+	if (*nextp == '\0')
+		return true;			/* allow empty string */
+
+	/* At the top of the loop, we are at start of a new directories. */
+	do
+	{
+		char	   *curname;
+		char	   *endp;
+
+		if (*nextp == '\"')
+		{
+			/* Quoted name --- collapse quote-quote pairs */
+			curname = nextp + 1;
+			for (;;)
+			{
+				endp = strchr(nextp + 1, '\"');
+				if (endp == NULL)
+					return false;		/* mismatched quotes */
+				if (endp[1] != '\"')
+					break;		/* found end of quoted name */
+				/* Collapse adjacent quotes into one quote, and look again */
+				memmove(endp, endp + 1, strlen(endp));
+				nextp = endp;
+			}
+			/* endp now points at the terminating quote */
+			nextp = endp + 1;
+		}
+		else
+		{
+			/* Unquoted name --- extends to separator or whitespace */
+			curname = nextp;
+			while (*nextp && *nextp != separator &&
+				   !isspace((unsigned char) *nextp))
+				nextp++;
+			endp = nextp;
+			if (curname == nextp)
+				return false;	/* empty unquoted name not allowed */
+		}
+
+		while (isspace((unsigned char) *nextp))
+			nextp++;			/* skip trailing whitespace */
+
+		if (*nextp == separator)
+		{
+			nextp++;
+			while (isspace((unsigned char) *nextp))
+				nextp++;		/* skip leading whitespace for next */
+			/* we expect another name, so done remains false */
+		}
+		else if (*nextp == '\0')
+			done = true;
+		else
+			return false;		/* invalid syntax */
+
+		/* Now safe to overwrite separator with a null */
+		*endp = '\0';
+
+		/* Truncate path if it's overlength */
+		if (strlen(curname) >= MAXPGPATH)
+			curname[MAXPGPATH-1] = '\0';
+
+		/*
+		 * Finished isolating current name --- add it to list
+		 */
+		*namelist = lappend(*namelist, pstrdup(curname));
+
+		/* Loop back if we didn't reach end of string */
+	} while (!done);
+
+	return true;
+}
+
 
 /*****************************************************************************
  *	Comparison Functions used for bytea
diff --git a/src/backend/utils/init/miscinit.c b/src/backend/utils/init/miscinit.c
index fb376a0..704c33c 100644
--- a/src/backend/utils/init/miscinit.c
+++ b/src/backend/utils/init/miscinit.c
@@ -663,10 +663,11 @@ UnlinkLockFile(int status, Datum filename)
  * filename is the name of the lockfile to create.
  * amPostmaster is used to determine how to encode the output PID.
  * isDDLock and refName are used to determine what error message to produce.
+ * socketPath is the path to the Unix socket we want to lock.
  */
 static void
 CreateLockFile(const char *filename, bool amPostmaster,
-			   bool isDDLock, const char *refName)
+			   bool isDDLock, const char *refName, const char *socketPath)
 {
 	int			fd;
 	char		buffer[MAXPGPATH * 2 + 256];
@@ -892,7 +893,8 @@ CreateLockFile(const char *filename, bool amPostmaster,
 			 (long) MyStartTime,
 			 PostPortNumber,
 #ifdef HAVE_UNIX_SOCKETS
-			 (*UnixSocketDir != '\0') ? UnixSocketDir : DEFAULT_PGSOCKET_DIR
+			 (socketPath && *socketPath != '\0') ? socketPath
+												 : DEFAULT_PGSOCKET_DIR
 #else
 			 ""
 #endif
@@ -947,21 +949,22 @@ CreateLockFile(const char *filename, bool amPostmaster,
  * helps ensure that we are locking the directory we should be.
  */
 void
-CreateDataDirLockFile(bool amPostmaster)
+CreateDataDirLockFile(bool amPostmaster, const char *socketDir)
 {
-	CreateLockFile(DIRECTORY_LOCK_FILE, amPostmaster, true, DataDir);
+	CreateLockFile(DIRECTORY_LOCK_FILE, amPostmaster, true, DataDir, socketDir);
 }
 
 /*
  * Create a lockfile for the specified Unix socket file.
  */
 void
-CreateSocketLockFile(const char *socketfile, bool amPostmaster)
+CreateSocketLockFile(const char *socketfile, bool amPostmaster, 
+					 const char *socketDir)
 {
 	char		lockfile[MAXPGPATH];
 
 	snprintf(lockfile, sizeof(lockfile), "%s.lock", socketfile);
-	CreateLockFile(lockfile, amPostmaster, false, socketfile);
+	CreateLockFile(lockfile, amPostmaster, false, socketfile, socketDir);
 	/* Save name of lockfile for TouchSocketLockFile */
 	strcpy(socketLockFile, lockfile);
 }
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index b756e58..bf90aff 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -2894,14 +2894,15 @@ static struct config_string ConfigureNamesString[] =
 	},
 
 	{
-		{"unix_socket_directory", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
-			gettext_noop("Sets the directory where the Unix-domain socket will be created."),
-			NULL,
+		{"unix_socket_directories", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
+			gettext_noop("Sets the directories where the Unix-domain socket will be created."),
+			gettext_noop("Directories are separated by \",\" and an additional "
+						"port number can be set, separated from directory by \":\"."),
 			GUC_SUPERUSER_ONLY
 		},
-		&UnixSocketDir,
+		&UnixSocketDirs,
 		"",
-		check_canonical_path, NULL, NULL
+		NULL, NULL, NULL
 	},
 
 	{
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index fa75d00..b7f9ac9 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -65,7 +65,8 @@
 # Note:  Increasing max_connections costs ~400 bytes of shared memory per
 # connection slot, plus lock space (see max_locks_per_transaction).
 #superuser_reserved_connections = 3	# (change requires restart)
-#unix_socket_directory = ''		# (change requires restart)
+#unix_socket_directories = ''		# comma-separated list of directories
+					# (change requires restart)
 #unix_socket_group = ''			# (change requires restart)
 #unix_socket_permissions = 0777		# begin with 0 to use octal notation
 					# (change requires restart)
diff --git a/src/bin/pg_ctl/pg_ctl.c b/src/bin/pg_ctl/pg_ctl.c
index d7b8367..a407684 100644
--- a/src/bin/pg_ctl/pg_ctl.c
+++ b/src/bin/pg_ctl/pg_ctl.c
@@ -521,14 +521,27 @@ test_postmaster_connection(bool do_checkpoint)
 						hostaddr = optlines[LOCK_FILE_LINE_LISTEN_ADDR - 1];
 
 						/*
-						 * While unix_socket_directory can accept relative
+						 * While unix_socket_directories can accept relative
 						 * directories, libpq's host parameter must have a
 						 * leading slash to indicate a socket directory.  So,
 						 * ignore sockdir if it's relative, and try to use TCP
 						 * instead.
 						 */
 						if (sockdir[0] == '/')
-							strlcpy(host_str, sockdir, sizeof(host_str));
+						{
+							char *rawstring;
+							char *comma;
+							
+							/* Need a modifiable copy of UnixSocketDirs */
+							rawstring = xstrdup(sockdir);
+							
+							/* We want only the first socket, in case more are defined */
+							if ((comma = strchr(rawstring, ',')) != NULL)
+								*comma = '\0';
+							
+							strlcpy(host_str, rawstring, sizeof(host_str));
+							free(rawstring);
+						}
 						else
 							strlcpy(host_str, hostaddr, sizeof(host_str));
 
diff --git a/src/include/miscadmin.h b/src/include/miscadmin.h
index b186eed..40802cf 100644
--- a/src/include/miscadmin.h
+++ b/src/include/miscadmin.h
@@ -398,8 +398,9 @@ extern char *local_preload_libraries_string;
 #define LOCK_FILE_LINE_LISTEN_ADDR	6
 #define LOCK_FILE_LINE_SHMEM_KEY	7
 
-extern void CreateDataDirLockFile(bool amPostmaster);
-extern void CreateSocketLockFile(const char *socketfile, bool amPostmaster);
+extern void CreateDataDirLockFile(bool amPostmaster, const char *socketDir);
+extern void CreateSocketLockFile(const char *socketfile, bool amPostmaster,
+								 const char *socketDir);
 extern void TouchSocketLockFile(void);
 extern void AddToDataDirLockFile(int target_line, const char *str);
 extern void ValidatePgVersion(const char *path);
diff --git a/src/include/postmaster/postmaster.h b/src/include/postmaster/postmaster.h
index 683ce3c..f19a3f8 100644
--- a/src/include/postmaster/postmaster.h
+++ b/src/include/postmaster/postmaster.h
@@ -19,7 +19,7 @@ extern int	ReservedBackends;
 extern int	PostPortNumber;
 extern int	Unix_socket_permissions;
 extern char *Unix_socket_group;
-extern char *UnixSocketDir;
+extern char *UnixSocketDirs;
 extern char *ListenAddresses;
 extern bool ClientAuthInProgress;
 extern int	PreAuthDelay;
diff --git a/src/include/utils/builtins.h b/src/include/utils/builtins.h
index d1e8370..65201fc 100644
--- a/src/include/utils/builtins.h
+++ b/src/include/utils/builtins.h
@@ -752,6 +752,8 @@ extern int	varstr_cmp(char *arg1, int len1, char *arg2, int len2, Oid collid);
 extern List *textToQualifiedNameList(text *textval);
 extern bool SplitIdentifierString(char *rawstring, char separator,
 					  List **namelist);
+extern bool SplitDirectoriesString(char *rawstring, char separator,
+					  List **namelist);
 extern Datum replace_text(PG_FUNCTION_ARGS);
 extern text *replace_text_regexp(text *src_text, void *regexp,
 					text *replace_text, bool glob);

diff --git a/doc/src/sgml/client-auth.sgml b/doc/src/sgml/client-auth.sgml
index cfdb33a..679c40a 100644
--- a/doc/src/sgml/client-auth.sgml
+++ b/doc/src/sgml/client-auth.sgml
@@ -838,7 +838,7 @@ omicron         bryanh                  guest1
     <varname>unix_socket_permissions</varname> (and possibly
     <varname>unix_socket_group</varname>) configuration parameters as
     described in <xref linkend="runtime-config-connection">.  Or you
-    could set the <varname>unix_socket_directory</varname>
+    could set the <varname>unix_socket_directories</varname>
     configuration parameter to place the socket file in a suitably
     restricted directory.
    </para>
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 074afee..d1727f8 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -453,17 +453,26 @@ SET ENABLE_SEQSCAN TO OFF;
       </listitem>
      </varlistentry>
 
-     <varlistentry id="guc-unix-socket-directory" xreflabel="unix_socket_directory">
-      <term><varname>unix_socket_directory</varname> (<type>string</type>)</term>
+     <varlistentry id="guc-unix-socket-directories" xreflabel="unix_socket_directories">
+      <term><varname>unix_socket_directories</varname> (<type>string</type>)</term>
       <indexterm>
-       <primary><varname>unix_socket_directory</> configuration parameter</primary>
+       <primary><varname>unix_socket_directories</> configuration parameter</primary>
       </indexterm>
       <listitem>
        <para>
-        Specifies the directory of the Unix-domain socket on which the
+        Specifies the directories of the Unix-domain sockets on which the
         server is to listen for
         connections from client applications.  The default is normally
         <filename>/tmp</filename>, but can be changed at build time.
+        Directories are separated by ',' and additional <replaceable>port</> 
+        number can be set, separated from directory by ':'. Port number will 
+        only be used as a part of the socket file name. For example,
+        <literal>'/var/run, /tmp:5431'</literal> would create socket files
+        <literal>/var/run/.s.PGSQL.5432</literal> and
+        <literal>/tmp/.s.PGSQL.5431</literal>. 
+        It is not possible to define <replaceable>port</> number in the first
+        entry. If set, it will be ignored and default <varname>port</>
+        will be used. 
         This parameter can only be set at server start.
        </para>
 
@@ -472,7 +481,7 @@ SET ENABLE_SEQSCAN TO OFF;
         <literal>.s.PGSQL.<replaceable>nnnn</></literal> where
         <replaceable>nnnn</> is the server's port number, an ordinary file
         named <literal>.s.PGSQL.<replaceable>nnnn</>.lock</literal> will be
-        created in the <varname>unix_socket_directory</> directory.  Neither
+        created in the <varname>unix_socket_directories</> directories.  Neither
         file should ever be removed manually.
        </para>
 
@@ -6593,7 +6602,7 @@ LOG:  CleanUpLock: deleting: lock(0xb7acd844) id(24688,24696,0,0,0,1)
        </row>
        <row>
         <entry><option>-k <replaceable>x</replaceable></option></entry>
-        <entry><literal>unix_socket_directory = <replaceable>x</replaceable></></entry>
+        <entry><literal>unix_socket_directories = <replaceable>x</replaceable></></entry>
        </row>
        <row>
         <entry><option>-l</option></entry>
diff --git a/doc/src/sgml/runtime.sgml b/doc/src/sgml/runtime.sgml
index 7ba18f0..6c74844 100644
--- a/doc/src/sgml/runtime.sgml
+++ b/doc/src/sgml/runtime.sgml
@@ -1784,7 +1784,7 @@ pg_dumpall -p 5432 | psql -d postgres -p 5433
   <para>
    The simplest way to prevent spoofing for <literal>local</>
    connections is to use a Unix domain socket directory (<xref
-   linkend="guc-unix-socket-directory">) that has write permission only
+   linkend="guc-unix-socket-directories">) that has write permission only
    for a trusted local user.  This prevents a malicious user from creating
    their own socket file in that directory.  If you are concerned that
    some applications might still reference <filename>/tmp</> for the
diff --git a/src/backend/bootstrap/bootstrap.c b/src/backend/bootstrap/bootstrap.c
index e3ae92d..50d4167 100644
--- a/src/backend/bootstrap/bootstrap.c
+++ b/src/backend/bootstrap/bootstrap.c
@@ -31,6 +31,7 @@
 #include "postmaster/bgwriter.h"
 #include "postmaster/startup.h"
 #include "postmaster/walwriter.h"
+#include "postmaster/postmaster.h"
 #include "replication/walreceiver.h"
 #include "storage/bufmgr.h"
 #include "storage/ipc.h"
@@ -349,7 +350,20 @@ AuxiliaryProcessMain(int argc, char *argv[])
 
 	/* If standalone, create lockfile for data directory */
 	if (!IsUnderPostmaster)
-		CreateDataDirLockFile(false);
+	{
+#ifdef HAVE_UNIX_SOCKETS
+		List	   *socketsList;
+		char	   *mainSocket = NULL;
+#endif
+		/*
+		 * We need to parse UnixSocketDirs here, because we want the first 
+		 * socket directory, which will be used in postmaster.pid. 
+		 */
+#ifdef HAVE_UNIX_SOCKETS
+		SplitUnixDirectories(UnixSocketDirs, &socketsList, &mainSocket);
+#endif
+		CreateDataDirLockFile(false, mainSocket);
+	}
 
 	SetProcessingMode(BootstrapProcessing);
 	IgnoreSystemIndexes = true;
diff --git a/src/backend/libpq/pqcomm.c b/src/backend/libpq/pqcomm.c
index 5272811..cf1e157 100644
--- a/src/backend/libpq/pqcomm.c
+++ b/src/backend/libpq/pqcomm.c
@@ -103,8 +103,8 @@ int			Unix_socket_permissions;
 char	   *Unix_socket_group;
 
 
-/* Where the Unix socket file is */
-static char sock_path[MAXPGPATH];
+/* Where the Unix socket files are */
+static List *sock_paths = NIL;
 
 
 /*
@@ -140,8 +140,8 @@ static int	internal_flush(void);
 static void pq_set_nonblocking(bool nonblocking);
 
 #ifdef HAVE_UNIX_SOCKETS
-static int	Lock_AF_UNIX(unsigned short portNumber, char *unixSocketName);
-static int	Setup_AF_UNIX(void);
+static int	Lock_AF_UNIX(unsigned short portNumber, char *unixSocketName, char **sock_path);
+static int	Setup_AF_UNIX(char *sock_path);
 #endif   /* HAVE_UNIX_SOCKETS */
 
 
@@ -234,14 +234,23 @@ pq_close(int code, Datum arg)
 
 /* StreamDoUnlink()
  * Shutdown routine for backend connection
- * If a Unix socket is used for communication, explicitly close it.
+ * If any Unix sockets are used for communication, explicitly close them.
  */
 #ifdef HAVE_UNIX_SOCKETS
 static void
 StreamDoUnlink(int code, Datum arg)
 {
-	Assert(sock_path[0]);
-	unlink(sock_path);
+	ListCell	*l;
+	char	*cursocket;
+	
+	/* Loop through all created sockets... */
+	foreach(l, sock_paths)
+	{
+		cursocket = (char *) lfirst(l);
+		unlink(cursocket);
+	}
+	list_free(sock_paths);
+	sock_paths = NIL;
 }
 #endif   /* HAVE_UNIX_SOCKETS */
 
@@ -286,10 +295,9 @@ StreamServerPort(int family, char *hostName, unsigned short portNumber,
 #ifdef HAVE_UNIX_SOCKETS
 	if (family == AF_UNIX)
 	{
-		/* Lock_AF_UNIX will also fill in sock_path. */
-		if (Lock_AF_UNIX(portNumber, unixSocketName) != STATUS_OK)
+		/* Lock_AF_UNIX will also fill in service. */
+		if (Lock_AF_UNIX(portNumber, unixSocketName, &service) != STATUS_OK)
 			return STATUS_ERROR;
-		service = sock_path;
 	}
 	else
 #endif   /* HAVE_UNIX_SOCKETS */
@@ -432,7 +440,7 @@ StreamServerPort(int family, char *hostName, unsigned short portNumber,
 					 (IS_AF_UNIX(addr->ai_family)) ?
 				  errhint("Is another postmaster already running on port %d?"
 						  " If not, remove socket file \"%s\" and retry.",
-						  (int) portNumber, sock_path) :
+						  (int) portNumber, service) :
 				  errhint("Is another postmaster already running on port %d?"
 						  " If not, wait a few seconds and retry.",
 						  (int) portNumber)));
@@ -443,7 +451,7 @@ StreamServerPort(int family, char *hostName, unsigned short portNumber,
 #ifdef HAVE_UNIX_SOCKETS
 		if (addr->ai_family == AF_UNIX)
 		{
-			if (Setup_AF_UNIX() != STATUS_OK)
+			if (Setup_AF_UNIX(service) != STATUS_OK)
 			{
 				closesocket(fd);
 				break;
@@ -490,9 +498,13 @@ StreamServerPort(int family, char *hostName, unsigned short portNumber,
  * Lock_AF_UNIX -- configure unix socket file path
  */
 static int
-Lock_AF_UNIX(unsigned short portNumber, char *unixSocketName)
+Lock_AF_UNIX(unsigned short portNumber, char *unixSocketName, char **sock_path)
 {
-	UNIXSOCK_PATH(sock_path, portNumber, unixSocketName);
+	char new_sock[MAXPGPATH];
+
+	UNIXSOCK_PATH(new_sock, portNumber, unixSocketName);
+
+	*sock_path = pstrdup(new_sock);
 
 	/*
 	 * Grab an interlock file associated with the socket file.
@@ -502,13 +514,14 @@ Lock_AF_UNIX(unsigned short portNumber, char *unixSocketName)
 	 * more portable, and second, it lets us remove any pre-existing socket
 	 * file without race conditions.
 	 */
-	CreateSocketLockFile(sock_path, true);
+	CreateSocketLockFile(*sock_path, true, unixSocketName);
 
 	/*
 	 * Once we have the interlock, we can safely delete any pre-existing
 	 * socket file to avoid failure at bind() time.
 	 */
-	unlink(sock_path);
+	unlink(*sock_path);
+	sock_paths = lappend(sock_paths, *sock_path);
 
 	return STATUS_OK;
 }
@@ -518,7 +531,7 @@ Lock_AF_UNIX(unsigned short portNumber, char *unixSocketName)
  * Setup_AF_UNIX -- configure unix socket permissions
  */
 static int
-Setup_AF_UNIX(void)
+Setup_AF_UNIX(char *sock_path)
 {
 	/* Arrange to unlink the socket file at exit */
 	on_proc_exit(StreamDoUnlink, 0);
@@ -707,17 +720,21 @@ StreamClose(pgsocket sock)
  * TouchSocketFile -- mark socket file as recently accessed
  *
  * This routine should be called every so often to ensure that the socket
- * file has a recent mod date (ordinary operations on sockets usually won't
- * change the mod date).  That saves it from being removed by
+ * files have a recent mod date (ordinary operations on sockets usually won't
+ * change the mod date).  That saves them from being removed by
  * overenthusiastic /tmp-directory-cleaner daemons.  (Another reason we should
- * never have put the socket file in /tmp...)
+ * never have put the socket files in /tmp...)
  */
 void
 TouchSocketFile(void)
 {
-	/* Do nothing if we did not create a socket... */
-	if (sock_path[0] != '\0')
+	ListCell	*l;
+	char	*cursocket;
+	
+	/* Loop through all created sockets... */
+	foreach(l, sock_paths)
 	{
+		cursocket = (char *) lfirst(l);
 		/*
 		 * utime() is POSIX standard, utimes() is a common alternative. If we
 		 * have neither, there's no way to affect the mod or access time of
@@ -726,10 +743,10 @@ TouchSocketFile(void)
 		 * In either path, we ignore errors; there's no point in complaining.
 		 */
 #ifdef HAVE_UTIME
-		utime(sock_path, NULL);
+		utime(cursocket, NULL);
 #else							/* !HAVE_UTIME */
 #ifdef HAVE_UTIMES
-		utimes(sock_path, NULL);
+		utimes(cursocket, NULL);
 #endif   /* HAVE_UTIMES */
 #endif   /* HAVE_UTIME */
 	}
diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c
index eeea933..0cc3521 100644
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -156,7 +156,7 @@ static Backend *ShmemBackendArray;
 
 /* The socket number we are listening for connections on */
 int			PostPortNumber;
-char	   *UnixSocketDir;
+char	   *UnixSocketDirs;
 char	   *ListenAddresses;
 
 /*
@@ -499,6 +499,10 @@ PostmasterMain(int argc, char *argv[])
 	char	   *userDoption = NULL;
 	bool		listen_addr_saved = false;
 	int			i;
+#ifdef HAVE_UNIX_SOCKETS
+	List	   *socketsList;
+	char	   *mainSocket = NULL;
+#endif
 
 	MyProcPid = PostmasterPid = getpid();
 
@@ -607,7 +611,7 @@ PostmasterMain(int argc, char *argv[])
 				break;
 
 			case 'k':
-				SetConfigOption("unix_socket_directory", optarg, PGC_POSTMASTER, PGC_S_ARGV);
+				SetConfigOption("unix_socket_directories", optarg, PGC_POSTMASTER, PGC_S_ARGV);
 				break;
 
 			case 'l':
@@ -807,6 +811,15 @@ PostmasterMain(int argc, char *argv[])
 	}
 
 	/*
+	 * We need to parse UnixSocketDirs here, because we want only 
+	 * the first socket directory be used in postmaster.pid, which is done
+	 * in CreateDataDirLockFile(). 
+	 */
+#ifdef HAVE_UNIX_SOCKETS
+	SplitUnixDirectories(UnixSocketDirs, &socketsList, &mainSocket);
+#endif
+
+	/*
 	 * Create lockfile for data directory.
 	 *
 	 * We want to do this before we try to grab the input sockets, because the
@@ -815,7 +828,7 @@ PostmasterMain(int argc, char *argv[])
 	 * For the same reason, it's best to grab the TCP socket(s) before the
 	 * Unix socket.
 	 */
-	CreateDataDirLockFile(true);
+	CreateDataDirLockFile(true, mainSocket);
 
 	/*
 	 * Initialize SSL library, if specified.
@@ -862,12 +875,12 @@ PostmasterMain(int argc, char *argv[])
 			if (strcmp(curhost, "*") == 0)
 				status = StreamServerPort(AF_UNSPEC, NULL,
 										  (unsigned short) PostPortNumber,
-										  UnixSocketDir,
+										  UnixSocketDirs,
 										  ListenSocket, MAXLISTEN);
 			else
 				status = StreamServerPort(AF_UNSPEC, curhost,
 										  (unsigned short) PostPortNumber,
-										  UnixSocketDir,
+										  UnixSocketDirs,
 										  ListenSocket, MAXLISTEN);
 
 			if (status == STATUS_OK)
@@ -933,13 +946,92 @@ PostmasterMain(int argc, char *argv[])
 #endif
 
 #ifdef HAVE_UNIX_SOCKETS
-	status = StreamServerPort(AF_UNIX, NULL,
-							  (unsigned short) PostPortNumber,
-							  UnixSocketDir,
-							  ListenSocket, MAXLISTEN);
-	if (status != STATUS_OK)
-		ereport(WARNING,
-				(errmsg("could not create Unix-domain socket")));
+	/* 
+	 * We can specify several directories for Unix sockets to listen on,
+	 * separated with ','. Socket name itself is the same in all cases.
+	 */
+	if (!UnixSocketDirs)
+	{
+		status = StreamServerPort(AF_UNIX, NULL,
+								  (unsigned short) PostPortNumber,
+								  UnixSocketDirs,
+								  ListenSocket, MAXLISTEN);
+		if (status != STATUS_OK)
+			ereport(WARNING,
+					(errmsg("could not create Unix-domain socket")));
+	
+	}
+	else
+	{
+		ListCell	*l;
+		bool		first = TRUE;
+
+		/* We have parse string into list of directories earlier */
+		foreach(l, socketsList)
+		{
+			char	*cursocket = (char *) lfirst(l);
+			char	*colon;
+			char	*port;
+			int64	portnum;
+			char	*endptr;
+			bool	bad_strtol;
+			
+			/* syntax is directory or directory:port, except the first one */
+			if ((colon = strrchr(cursocket, ':')) != NULL)
+			{
+				port = colon + 1;
+				*colon = '\0';
+				
+				/*
+				 * convert port number to integer, ignoring optional trailing
+				 * whitespace).  strtol should ignore leading whitespace, too.
+				 */
+				portnum = strtol(port, &endptr, 0);
+				bad_strtol = (errno == ERANGE);
+
+				while (isspace((unsigned char) *endptr))
+					endptr++;
+
+				if (*endptr != '\0')
+				ereport(FATAL,
+						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+						 errmsg("port number \"%s\" invalid in \"unix_socket_directories\"", port)));
+
+				if (bad_strtol || portnum < 1 || portnum > 65535)
+					ereport(FATAL,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("port number \"%s\" out of range in \"unix_socket_directories\"", port)));
+				if (first)
+					portnum = PostPortNumber;
+			}
+			else
+			{
+				portnum = PostPortNumber;
+			}
+			first = FALSE;
+
+			/* only absolute paths are allowed */
+			canonicalize_path(cursocket);
+			if (!is_absolute_path(cursocket))
+			{
+				ereport(FATAL,
+						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+						 errmsg("directory \"%s\" is not an absolute path", cursocket)));
+			}
+			else
+			{
+				status = StreamServerPort(AF_UNIX, NULL,
+					(unsigned short) portnum,
+					cursocket,
+					ListenSocket, MAXLISTEN);
+				if (status != STATUS_OK)
+				ereport(FATAL,
+					(errmsg("could not create secondary Unix-domain socket at \"%s\"", cursocket)));
+			}
+		}
+		
+		list_free(socketsList);
+	}
 #endif
 
 	/*
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 51b6df5..22c8228 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -3343,7 +3343,7 @@ process_postgres_switches(int argc, char *argv[], GucContext ctx)
 				break;
 
 			case 'k':
-				SetConfigOption("unix_socket_directory", optarg, ctx, gucsource);
+				SetConfigOption("unix_socket_directories", optarg, ctx, gucsource);
 				break;
 
 			case 'l':
@@ -3647,6 +3647,10 @@ PostgresMain(int argc, char *argv[], const char *username)
 
 	if (!IsUnderPostmaster)
 	{
+#ifdef HAVE_UNIX_SOCKETS
+		List	   *socketsList;
+		char	   *mainSocket = NULL;
+#endif
 		/*
 		 * Validate we have been given a reasonable-looking DataDir (if under
 		 * postmaster, assume postmaster did this already).
@@ -3658,9 +3662,16 @@ PostgresMain(int argc, char *argv[], const char *username)
 		ChangeToDataDir();
 
 		/*
+		 * We need to parse UnixSocketDirs here, because we want the first 
+		 * socket directory, which will be used in postmaster.pid. 
+		 */
+#ifdef HAVE_UNIX_SOCKETS
+		SplitUnixDirectories(UnixSocketDirs, &socketsList, &mainSocket);
+#endif
+		/*
 		 * Create lockfile for data directory.
 		 */
-		CreateDataDirLockFile(false);
+		CreateDataDirLockFile(false, mainSocket);
 	}
 
 	/* Early initialization */
diff --git a/src/backend/utils/adt/varlena.c b/src/backend/utils/adt/varlena.c
index e1b57ba..466d738 100644
--- a/src/backend/utils/adt/varlena.c
+++ b/src/backend/utils/adt/varlena.c
@@ -2445,6 +2445,155 @@ SplitIdentifierString(char *rawstring, char separator,
 	return true;
 }
 
+/*
+ * SplitDirectoriesString --- parse a string containing directories
+ *
+ * Inputs:
+ *	rawstring: the input string; must be overwritable!	On return, it's
+ *			   been modified to contain the separated directories.
+ *	separator: the separator punctuation expected between directories
+ *			   (typically ',' or ';').	Whitespace may also appear around
+ *			   directories.
+ * Outputs:
+ *	namelist: filled with a palloc'd list of pointers to directories within
+ *			  rawstring.  Caller should list_free() this even on error return.
+ *
+ * Returns TRUE if okay, FALSE if there is a syntax error in the string.
+ *
+ * Note that an empty string is considered okay here.
+ */
+bool
+SplitDirectoriesString(char *rawstring, char separator,
+					  List **namelist)
+{
+	char	   *nextp = rawstring;
+	bool		done = false;
+
+	*namelist = NIL;
+
+	while (isspace((unsigned char) *nextp))
+		nextp++;				/* skip leading whitespace */
+
+	if (*nextp == '\0')
+		return true;			/* allow empty string */
+
+	/* At the top of the loop, we are at start of a new directories. */
+	do
+	{
+		char	   *curname;
+		char	   *endp;
+
+		if (*nextp == '\"')
+		{
+			/* Quoted name --- collapse quote-quote pairs */
+			curname = nextp + 1;
+			for (;;)
+			{
+				endp = strchr(nextp + 1, '\"');
+				if (endp == NULL)
+					return false;		/* mismatched quotes */
+				if (endp[1] != '\"')
+					break;		/* found end of quoted name */
+				/* Collapse adjacent quotes into one quote, and look again */
+				memmove(endp, endp + 1, strlen(endp));
+				nextp = endp;
+			}
+			/* endp now points at the terminating quote */
+			nextp = endp + 1;
+		}
+		else
+		{
+			/* Unquoted name --- extends to separator or whitespace */
+			curname = nextp;
+			while (*nextp && *nextp != separator &&
+				   !isspace((unsigned char) *nextp))
+				nextp++;
+			endp = nextp;
+			if (curname == nextp)
+				return false;	/* empty unquoted name not allowed */
+		}
+
+		while (isspace((unsigned char) *nextp))
+			nextp++;			/* skip trailing whitespace */
+
+		if (*nextp == separator)
+		{
+			nextp++;
+			while (isspace((unsigned char) *nextp))
+				nextp++;		/* skip leading whitespace for next */
+			/* we expect another name, so done remains false */
+		}
+		else if (*nextp == '\0')
+			done = true;
+		else
+			return false;		/* invalid syntax */
+
+		/* Now safe to overwrite separator with a null */
+		*endp = '\0';
+
+		/* Truncate path if it's overlength */
+		if (strlen(curname) >= MAXPGPATH)
+			curname[MAXPGPATH-1] = '\0';
+
+		/*
+		 * Finished isolating current name --- add it to list
+		 */
+		*namelist = lappend(*namelist, pstrdup(curname));
+
+		/* Loop back if we didn't reach end of string */
+	} while (!done);
+
+	return true;
+}
+
+/*
+ * parse UnixSocketDirs as a list of directory[:port], return the list
+ * in socketsList and store the first item into mainSocket.
+ */
+void
+SplitUnixDirectories(char *unixSocketDirs, List **socketsList,
+					 char **mainSocket)
+{
+#ifdef HAVE_UNIX_SOCKETS
+	if (unixSocketDirs)
+	{
+		char	   *rawSocketsString;
+		ListCell   *l;
+
+		/* Need a modifiable copy of UnixSocketDirs */
+		rawSocketsString = pstrdup(unixSocketDirs);
+		
+		/* Parse string into list of directories */
+		if (!SplitDirectoriesString(rawSocketsString, ',', socketsList))
+		{
+			/* syntax error in list */
+			ereport(FATAL,
+				   (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							errmsg("invalid list syntax for \"unix_socket_directories\"")));
+		}
+
+		pfree(rawSocketsString);
+
+		if (l = list_head(*socketsList))
+		{
+			char *colon;
+			
+			*mainSocket = (char *) lfirst(l);
+			
+			/* 
+			 * the first unix socket directory cannot contain :port
+			 * and the default port is used every-time, so strip the port 
+			 */
+			if ((colon = strrchr(*mainSocket, ':')) != NULL)
+				*colon = '\0';
+		}
+		else
+			*mainSocket = unixSocketDirs;
+	}
+	else
+		*mainSocket = unixSocketDirs;
+#endif
+}
 
 /*****************************************************************************
  *	Comparison Functions used for bytea
diff --git a/src/backend/utils/init/miscinit.c b/src/backend/utils/init/miscinit.c
index fb376a0..670e1a7 100644
--- a/src/backend/utils/init/miscinit.c
+++ b/src/backend/utils/init/miscinit.c
@@ -663,10 +663,11 @@ UnlinkLockFile(int status, Datum filename)
  * filename is the name of the lockfile to create.
  * amPostmaster is used to determine how to encode the output PID.
  * isDDLock and refName are used to determine what error message to produce.
+ * socketPath is the path to the Unix socket we want to lock.
  */
 static void
 CreateLockFile(const char *filename, bool amPostmaster,
-			   bool isDDLock, const char *refName)
+			   bool isDDLock, const char *refName, const char *socketPath)
 {
 	int			fd;
 	char		buffer[MAXPGPATH * 2 + 256];
@@ -892,7 +893,8 @@ CreateLockFile(const char *filename, bool amPostmaster,
 			 (long) MyStartTime,
 			 PostPortNumber,
 #ifdef HAVE_UNIX_SOCKETS
-			 (*UnixSocketDir != '\0') ? UnixSocketDir : DEFAULT_PGSOCKET_DIR
+			 (socketPath && *socketPath != '\0') ? socketPath
+												 : DEFAULT_PGSOCKET_DIR
 #else
 			 ""
 #endif
@@ -947,21 +949,22 @@ CreateLockFile(const char *filename, bool amPostmaster,
  * helps ensure that we are locking the directory we should be.
  */
 void
-CreateDataDirLockFile(bool amPostmaster)
+CreateDataDirLockFile(bool amPostmaster, const char *socketDir)
 {
-	CreateLockFile(DIRECTORY_LOCK_FILE, amPostmaster, true, DataDir);
+	CreateLockFile(DIRECTORY_LOCK_FILE, amPostmaster, true, DataDir, socketDir);
 }
 
 /*
  * Create a lockfile for the specified Unix socket file.
  */
 void
-CreateSocketLockFile(const char *socketfile, bool amPostmaster)
+CreateSocketLockFile(const char *socketfile, bool amPostmaster, 
+					 const char *socketDir)
 {
 	char		lockfile[MAXPGPATH];
 
 	snprintf(lockfile, sizeof(lockfile), "%s.lock", socketfile);
-	CreateLockFile(lockfile, amPostmaster, false, socketfile);
+	CreateLockFile(lockfile, amPostmaster, false, socketfile, socketDir);
 	/* Save name of lockfile for TouchSocketLockFile */
 	strcpy(socketLockFile, lockfile);
 }
@@ -1292,3 +1295,4 @@ pg_bindtextdomain(const char *domain)
 	}
 #endif
 }
+
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index b756e58..bf90aff 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -2894,14 +2894,15 @@ static struct config_string ConfigureNamesString[] =
 	},
 
 	{
-		{"unix_socket_directory", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
-			gettext_noop("Sets the directory where the Unix-domain socket will be created."),
-			NULL,
+		{"unix_socket_directories", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
+			gettext_noop("Sets the directories where the Unix-domain socket will be created."),
+			gettext_noop("Directories are separated by \",\" and an additional "
+						"port number can be set, separated from directory by \":\"."),
 			GUC_SUPERUSER_ONLY
 		},
-		&UnixSocketDir,
+		&UnixSocketDirs,
 		"",
-		check_canonical_path, NULL, NULL
+		NULL, NULL, NULL
 	},
 
 	{
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index fa75d00..1eea8aa 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -65,7 +65,9 @@
 # Note:  Increasing max_connections costs ~400 bytes of shared memory per
 # connection slot, plus lock space (see max_locks_per_transaction).
 #superuser_reserved_connections = 3	# (change requires restart)
-#unix_socket_directory = ''		# (change requires restart)
+#unix_socket_directories = ''		# comma-separated list of directories:port,
+					# while the first socket's port is the default one
+					# (change requires restart)
 #unix_socket_group = ''			# (change requires restart)
 #unix_socket_permissions = 0777		# begin with 0 to use octal notation
 					# (change requires restart)
diff --git a/src/bin/pg_ctl/pg_ctl.c b/src/bin/pg_ctl/pg_ctl.c
index 3826312..6d811ff 100644
--- a/src/bin/pg_ctl/pg_ctl.c
+++ b/src/bin/pg_ctl/pg_ctl.c
@@ -521,7 +521,7 @@ test_postmaster_connection(bool do_checkpoint)
 						hostaddr = optlines[LOCK_FILE_LINE_LISTEN_ADDR - 1];
 
 						/*
-						 * While unix_socket_directory can accept relative
+						 * While unix_socket_directories can accept relative
 						 * directories, libpq's host parameter must have a
 						 * leading slash to indicate a socket directory.  So,
 						 * ignore sockdir if it's relative, and try to use TCP
diff --git a/src/include/miscadmin.h b/src/include/miscadmin.h
index b186eed..40802cf 100644
--- a/src/include/miscadmin.h
+++ b/src/include/miscadmin.h
@@ -398,8 +398,9 @@ extern char *local_preload_libraries_string;
 #define LOCK_FILE_LINE_LISTEN_ADDR	6
 #define LOCK_FILE_LINE_SHMEM_KEY	7
 
-extern void CreateDataDirLockFile(bool amPostmaster);
-extern void CreateSocketLockFile(const char *socketfile, bool amPostmaster);
+extern void CreateDataDirLockFile(bool amPostmaster, const char *socketDir);
+extern void CreateSocketLockFile(const char *socketfile, bool amPostmaster,
+								 const char *socketDir);
 extern void TouchSocketLockFile(void);
 extern void AddToDataDirLockFile(int target_line, const char *str);
 extern void ValidatePgVersion(const char *path);
diff --git a/src/include/postmaster/postmaster.h b/src/include/postmaster/postmaster.h
index 683ce3c..f19a3f8 100644
--- a/src/include/postmaster/postmaster.h
+++ b/src/include/postmaster/postmaster.h
@@ -19,7 +19,7 @@ extern int	ReservedBackends;
 extern int	PostPortNumber;
 extern int	Unix_socket_permissions;
 extern char *Unix_socket_group;
-extern char *UnixSocketDir;
+extern char *UnixSocketDirs;
 extern char *ListenAddresses;
 extern bool ClientAuthInProgress;
 extern int	PreAuthDelay;
diff --git a/src/include/utils/builtins.h b/src/include/utils/builtins.h
index d1e8370..492a08e 100644
--- a/src/include/utils/builtins.h
+++ b/src/include/utils/builtins.h
@@ -752,6 +752,10 @@ extern int	varstr_cmp(char *arg1, int len1, char *arg2, int len2, Oid collid);
 extern List *textToQualifiedNameList(text *textval);
 extern bool SplitIdentifierString(char *rawstring, char separator,
 					  List **namelist);
+extern bool SplitDirectoriesString(char *rawstring, char separator,
+					  List **namelist);
+extern void SplitUnixDirectories(char *unixSocketDirs, List **socketsList,
+					  char **mainSocket);
 extern Datum replace_text(PG_FUNCTION_ARGS);
 extern text *replace_text_regexp(text *src_text, void *regexp,
 					text *replace_text, bool glob);

diff --git a/doc/src/sgml/client-auth.sgml b/doc/src/sgml/client-auth.sgml
index cfdb33a..679c40a 100644
--- a/doc/src/sgml/client-auth.sgml
+++ b/doc/src/sgml/client-auth.sgml
@@ -838,7 +838,7 @@ omicron         bryanh                  guest1
     <varname>unix_socket_permissions</varname> (and possibly
     <varname>unix_socket_group</varname>) configuration parameters as
     described in <xref linkend="runtime-config-connection">.  Or you
-    could set the <varname>unix_socket_directory</varname>
+    could set the <varname>unix_socket_directories</varname>
     configuration parameter to place the socket file in a suitably
     restricted directory.
    </para>
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 3a0b16d..67997d6 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -445,17 +445,18 @@ SET ENABLE_SEQSCAN TO OFF;
       </listitem>
      </varlistentry>
 
-     <varlistentry id="guc-unix-socket-directory" xreflabel="unix_socket_directory">
-      <term><varname>unix_socket_directory</varname> (<type>string</type>)</term>
+     <varlistentry id="guc-unix-socket-directories" xreflabel="unix_socket_directories">
+      <term><varname>unix_socket_directories</varname> (<type>string</type>)</term>
       <indexterm>
-       <primary><varname>unix_socket_directory</> configuration parameter</primary>
+       <primary><varname>unix_socket_directories</> configuration parameter</primary>
       </indexterm>
       <listitem>
        <para>
-        Specifies the directory of the Unix-domain socket on which the
+        Specifies the directories of the Unix-domain sockets on which the
         server is to listen for
         connections from client applications.  The default is normally
         <filename>/tmp</filename>, but can be changed at build time.
+        Directories are separated by ','.
         This parameter can only be set at server start.
        </para>
 
@@ -464,7 +465,7 @@ SET ENABLE_SEQSCAN TO OFF;
         <literal>.s.PGSQL.<replaceable>nnnn</></literal> where
         <replaceable>nnnn</> is the server's port number, an ordinary file
         named <literal>.s.PGSQL.<replaceable>nnnn</>.lock</literal> will be
-        created in the <varname>unix_socket_directory</> directory.  Neither
+        created in the <varname>unix_socket_directories</> directories.  Neither
         file should ever be removed manually.
        </para>
 
@@ -6551,7 +6552,7 @@ LOG:  CleanUpLock: deleting: lock(0xb7acd844) id(24688,24696,0,0,0,1)
        </row>
        <row>
         <entry><option>-k <replaceable>x</replaceable></option></entry>
-        <entry><literal>unix_socket_directory = <replaceable>x</replaceable></></entry>
+        <entry><literal>unix_socket_directories = <replaceable>x</replaceable></></entry>
        </row>
        <row>
         <entry><option>-l</option></entry>
diff --git a/doc/src/sgml/runtime.sgml b/doc/src/sgml/runtime.sgml
index 8717798..9cc9d42 100644
--- a/doc/src/sgml/runtime.sgml
+++ b/doc/src/sgml/runtime.sgml
@@ -1718,7 +1718,7 @@ pg_dumpall -p 5432 | psql -d postgres -p 5433
   <para>
    The simplest way to prevent spoofing for <literal>local</>
    connections is to use a Unix domain socket directory (<xref
-   linkend="guc-unix-socket-directory">) that has write permission only
+   linkend="guc-unix-socket-directories">) that has write permission only
    for a trusted local user.  This prevents a malicious user from creating
    their own socket file in that directory.  If you are concerned that
    some applications might still reference <filename>/tmp</> for the
diff --git a/src/backend/libpq/pqcomm.c b/src/backend/libpq/pqcomm.c
index 5272811..3e22388 100644
--- a/src/backend/libpq/pqcomm.c
+++ b/src/backend/libpq/pqcomm.c
@@ -103,8 +103,8 @@ int			Unix_socket_permissions;
 char	   *Unix_socket_group;
 
 
-/* Where the Unix socket file is */
-static char sock_path[MAXPGPATH];
+/* Where the Unix socket files are */
+static List *sock_paths = NIL;
 
 
 /*
@@ -140,8 +140,9 @@ static int	internal_flush(void);
 static void pq_set_nonblocking(bool nonblocking);
 
 #ifdef HAVE_UNIX_SOCKETS
-static int	Lock_AF_UNIX(unsigned short portNumber, char *unixSocketName);
-static int	Setup_AF_UNIX(void);
+static int	Lock_AF_UNIX(unsigned short portNumber, char *unixSocketDir,
+						 char *unixSocketPath);
+static int	Setup_AF_UNIX(char *sock_path);
 #endif   /* HAVE_UNIX_SOCKETS */
 
 
@@ -234,14 +235,23 @@ pq_close(int code, Datum arg)
 
 /* StreamDoUnlink()
  * Shutdown routine for backend connection
- * If a Unix socket is used for communication, explicitly close it.
+ * If any Unix sockets are used for communication, explicitly close them.
  */
 #ifdef HAVE_UNIX_SOCKETS
 static void
 StreamDoUnlink(int code, Datum arg)
 {
-	Assert(sock_path[0]);
-	unlink(sock_path);
+	ListCell	*l;
+	char	*cursocket;
+	
+	/* Loop through all created sockets... */
+	foreach(l, sock_paths)
+	{
+		cursocket = (char *) lfirst(l);
+		unlink(cursocket);
+	}
+	list_free(sock_paths);
+	sock_paths = NIL;
 }
 #endif   /* HAVE_UNIX_SOCKETS */
 
@@ -256,7 +266,7 @@ StreamDoUnlink(int code, Datum arg)
 
 int
 StreamServerPort(int family, char *hostName, unsigned short portNumber,
-				 char *unixSocketName,
+				 char *unixSocketDir,
 				 pgsocket ListenSocket[], int MaxListen)
 {
 	pgsocket	fd;
@@ -267,6 +277,7 @@ StreamServerPort(int family, char *hostName, unsigned short portNumber,
 	const char *familyDesc;
 	char		familyDescBuf[64];
 	char	   *service;
+	char		unixSocketPath[MAXPGPATH];
 	struct addrinfo *addrs = NULL,
 			   *addr;
 	struct addrinfo hint;
@@ -286,10 +297,14 @@ StreamServerPort(int family, char *hostName, unsigned short portNumber,
 #ifdef HAVE_UNIX_SOCKETS
 	if (family == AF_UNIX)
 	{
-		/* Lock_AF_UNIX will also fill in sock_path. */
-		if (Lock_AF_UNIX(portNumber, unixSocketName) != STATUS_OK)
+		/*
+		 * Create unixSocketPath from portNumber and unixSocketDir
+		 * and lock that file
+		 */
+		UNIXSOCK_PATH(unixSocketPath, portNumber, unixSocketDir);
+		if (Lock_AF_UNIX(portNumber, unixSocketDir, unixSocketPath) != STATUS_OK)
 			return STATUS_ERROR;
-		service = sock_path;
+		service = unixSocketPath;
 	}
 	else
 #endif   /* HAVE_UNIX_SOCKETS */
@@ -432,7 +447,7 @@ StreamServerPort(int family, char *hostName, unsigned short portNumber,
 					 (IS_AF_UNIX(addr->ai_family)) ?
 				  errhint("Is another postmaster already running on port %d?"
 						  " If not, remove socket file \"%s\" and retry.",
-						  (int) portNumber, sock_path) :
+						  (int) portNumber, service) :
 				  errhint("Is another postmaster already running on port %d?"
 						  " If not, wait a few seconds and retry.",
 						  (int) portNumber)));
@@ -443,7 +458,7 @@ StreamServerPort(int family, char *hostName, unsigned short portNumber,
 #ifdef HAVE_UNIX_SOCKETS
 		if (addr->ai_family == AF_UNIX)
 		{
-			if (Setup_AF_UNIX() != STATUS_OK)
+			if (Setup_AF_UNIX(service) != STATUS_OK)
 			{
 				closesocket(fd);
 				break;
@@ -490,10 +505,8 @@ StreamServerPort(int family, char *hostName, unsigned short portNumber,
  * Lock_AF_UNIX -- configure unix socket file path
  */
 static int
-Lock_AF_UNIX(unsigned short portNumber, char *unixSocketName)
+Lock_AF_UNIX(unsigned short portNumber, char *unixSocketDir, char *unixSocketPath)
 {
-	UNIXSOCK_PATH(sock_path, portNumber, unixSocketName);
-
 	/*
 	 * Grab an interlock file associated with the socket file.
 	 *
@@ -502,13 +515,19 @@ Lock_AF_UNIX(unsigned short portNumber, char *unixSocketName)
 	 * more portable, and second, it lets us remove any pre-existing socket
 	 * file without race conditions.
 	 */
-	CreateSocketLockFile(sock_path, true);
+	CreateSocketLockFile(unixSocketPath, true, unixSocketDir);
 
 	/*
 	 * Once we have the interlock, we can safely delete any pre-existing
 	 * socket file to avoid failure at bind() time.
 	 */
-	unlink(sock_path);
+	unlink(unixSocketPath);
+	
+	/*
+	 * Add a new socket file to the list, so we always know which socket
+	 * paths exist and should be removed in the end.
+	 */
+	sock_paths = lappend(sock_paths, pstrdup(unixSocketPath));
 
 	return STATUS_OK;
 }
@@ -518,7 +537,7 @@ Lock_AF_UNIX(unsigned short portNumber, char *unixSocketName)
  * Setup_AF_UNIX -- configure unix socket permissions
  */
 static int
-Setup_AF_UNIX(void)
+Setup_AF_UNIX(char *sock_path)
 {
 	/* Arrange to unlink the socket file at exit */
 	on_proc_exit(StreamDoUnlink, 0);
@@ -707,17 +726,21 @@ StreamClose(pgsocket sock)
  * TouchSocketFile -- mark socket file as recently accessed
  *
  * This routine should be called every so often to ensure that the socket
- * file has a recent mod date (ordinary operations on sockets usually won't
- * change the mod date).  That saves it from being removed by
+ * files have a recent mod date (ordinary operations on sockets usually won't
+ * change the mod date).  That saves them from being removed by
  * overenthusiastic /tmp-directory-cleaner daemons.  (Another reason we should
- * never have put the socket file in /tmp...)
+ * never have put the socket files in /tmp...)
  */
 void
 TouchSocketFile(void)
 {
-	/* Do nothing if we did not create a socket... */
-	if (sock_path[0] != '\0')
+	ListCell	*l;
+	char	*cursocket;
+	
+	/* Loop through all created sockets... */
+	foreach(l, sock_paths)
 	{
+		cursocket = (char *) lfirst(l);
 		/*
 		 * utime() is POSIX standard, utimes() is a common alternative. If we
 		 * have neither, there's no way to affect the mod or access time of
@@ -726,10 +749,10 @@ TouchSocketFile(void)
 		 * In either path, we ignore errors; there's no point in complaining.
 		 */
 #ifdef HAVE_UTIME
-		utime(sock_path, NULL);
+		utime(cursocket, NULL);
 #else							/* !HAVE_UTIME */
 #ifdef HAVE_UTIMES
-		utimes(sock_path, NULL);
+		utimes(cursocket, NULL);
 #endif   /* HAVE_UTIMES */
 #endif   /* HAVE_UTIME */
 	}
diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c
index 45f6ac6..a89455f 100644
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -156,7 +156,8 @@ static Backend *ShmemBackendArray;
 
 /* The socket number we are listening for connections on */
 int			PostPortNumber;
-char	   *UnixSocketDir;
+char	   *UnixSocketDirs;
+List	   *UnixSocketDirList;
 char	   *ListenAddresses;
 
 /*
@@ -609,7 +610,7 @@ PostmasterMain(int argc, char *argv[])
 				break;
 
 			case 'k':
-				SetConfigOption("unix_socket_directory", optarg, PGC_POSTMASTER, PGC_S_ARGV);
+				SetConfigOption("unix_socket_directories", optarg, PGC_POSTMASTER, PGC_S_ARGV);
 				break;
 
 			case 'l':
@@ -838,6 +839,47 @@ PostmasterMain(int argc, char *argv[])
 	for (i = 0; i < MAXLISTEN; i++)
 		ListenSocket[i] = PGINVALID_SOCKET;
 
+#ifdef HAVE_UNIX_SOCKETS
+	/*
+	 * We can specify several directories for Unix sockets to listen on,
+	 * separated with ','. Socket name itself is the same in all cases.
+	 */
+	{
+		int			success = 0;
+		bool		listen_socket_saved = false;
+		ListCell   *l;
+
+		foreach(l, UnixSocketDirList)
+		{
+			char	*cursocket = (char *) lfirst(l);
+
+			status = StreamServerPort(AF_UNIX, NULL,
+				(unsigned short) PostPortNumber,
+				cursocket,
+				ListenSocket, MAXLISTEN);
+
+			if (status == STATUS_OK)
+			{
+				success++;
+				/* record the first successful unix socket in lockfile */
+				if (!listen_socket_saved)
+				{
+					AddToDataDirLockFile(LOCK_FILE_LINE_SOCKET_DIR, cursocket);
+					listen_socket_saved = true;
+				}
+			}
+			else
+				ereport(WARNING,
+						(errmsg("could not create Unix-domain socket at \"%s\"", cursocket)));
+
+		}
+
+		if (!success && list_length(UnixSocketDirList))
+			ereport(FATAL,
+					(errmsg("could not create any Unix-domain sockets")));
+	}
+#endif
+
 	if (ListenAddresses)
 	{
 		char	   *rawstring;
@@ -864,12 +906,12 @@ PostmasterMain(int argc, char *argv[])
 			if (strcmp(curhost, "*") == 0)
 				status = StreamServerPort(AF_UNSPEC, NULL,
 										  (unsigned short) PostPortNumber,
-										  UnixSocketDir,
+										  NULL,
 										  ListenSocket, MAXLISTEN);
 			else
 				status = StreamServerPort(AF_UNSPEC, curhost,
 										  (unsigned short) PostPortNumber,
-										  UnixSocketDir,
+										  NULL,
 										  ListenSocket, MAXLISTEN);
 
 			if (status == STATUS_OK)
@@ -934,16 +976,6 @@ PostmasterMain(int argc, char *argv[])
 	}
 #endif
 
-#ifdef HAVE_UNIX_SOCKETS
-	status = StreamServerPort(AF_UNIX, NULL,
-							  (unsigned short) PostPortNumber,
-							  UnixSocketDir,
-							  ListenSocket, MAXLISTEN);
-	if (status != STATUS_OK)
-		ereport(WARNING,
-				(errmsg("could not create Unix-domain socket")));
-#endif
-
 	/*
 	 * check that we have some socket to listen on
 	 */
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 9a5438f..265fad9 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -3343,7 +3343,7 @@ process_postgres_switches(int argc, char *argv[], GucContext ctx)
 				break;
 
 			case 'k':
-				SetConfigOption("unix_socket_directory", optarg, ctx, gucsource);
+				SetConfigOption("unix_socket_directories", optarg, ctx, gucsource);
 				break;
 
 			case 'l':
diff --git a/src/backend/utils/adt/varlena.c b/src/backend/utils/adt/varlena.c
index e1b57ba..bddc972 100644
--- a/src/backend/utils/adt/varlena.c
+++ b/src/backend/utils/adt/varlena.c
@@ -2445,6 +2445,109 @@ SplitIdentifierString(char *rawstring, char separator,
 	return true;
 }
 
+/*
+ * SplitDirectoriesString --- parse a string containing directories
+ *
+ * Inputs:
+ *	rawstring: the input string; must be overwritable!	On return, it's
+ *			   been modified to contain the separated directories.
+ *	separator: the separator punctuation expected between directories
+ *			   (typically ',' or ';').	Whitespace may also appear around
+ *			   directories.
+ * Outputs:
+ *	namelist: filled with a palloc'd list of pointers to directories within
+ *			  rawstring.  Caller should list_free() this even on error return.
+ *
+ * Returns TRUE if okay, FALSE if there is a syntax error in the string.
+ *
+ * Note that an empty string is considered okay here.
+ */
+bool
+SplitDirectoriesString(char *rawstring, char separator,
+					  List **namelist)
+{
+	char	   *nextp = rawstring;
+	bool		done = false;
+	char	   *tmpname;
+
+	*namelist = NIL;
+
+	while (isspace((unsigned char) *nextp))
+		nextp++;				/* skip leading whitespace */
+
+	if (*nextp == '\0')
+		return true;			/* allow empty string */
+
+	/* At the top of the loop, we are at start of a new directories. */
+	do
+	{
+		char	   *curname;
+		char	   *endp;
+
+		if (*nextp == '\"')
+		{
+			/* Quoted name --- collapse quote-quote pairs */
+			curname = nextp + 1;
+			for (;;)
+			{
+				endp = strchr(nextp + 1, '\"');
+				if (endp == NULL)
+					return false;		/* mismatched quotes */
+				if (endp[1] != '\"')
+					break;		/* found end of quoted name */
+				/* Collapse adjacent quotes into one quote, and look again */
+				memmove(endp, endp + 1, strlen(endp));
+				nextp = endp;
+			}
+			/* endp now points at the terminating quote */
+			nextp = endp + 1;
+		}
+		else
+		{
+			/* Unquoted name --- extends to separator or whitespace */
+			curname = nextp;
+			while (*nextp && *nextp != separator &&
+				   !isspace((unsigned char) *nextp))
+				nextp++;
+			endp = nextp;
+			if (curname == nextp)
+				return false;	/* empty unquoted name not allowed */
+		}
+
+		while (isspace((unsigned char) *nextp))
+			nextp++;			/* skip trailing whitespace */
+
+		if (*nextp == separator)
+		{
+			nextp++;
+			while (isspace((unsigned char) *nextp))
+				nextp++;		/* skip leading whitespace for next */
+			/* we expect another name, so done remains false */
+		}
+		else if (*nextp == '\0')
+			done = true;
+		else
+			return false;		/* invalid syntax */
+
+		/* Now safe to overwrite separator with a null */
+		*endp = '\0';
+
+		/* Truncate path if it's overlength */
+		if (strlen(curname) >= MAXPGPATH)
+			curname[MAXPGPATH-1] = '\0';
+
+		/*
+		 * Finished isolating current name --- add it to list
+		 */
+		tmpname = pstrdup(curname);
+		canonicalize_path(tmpname);
+		*namelist = lappend(*namelist, tmpname);
+
+		/* Loop back if we didn't reach end of string */
+	} while (!done);
+
+	return true;
+}
 
 /*****************************************************************************
  *	Comparison Functions used for bytea
diff --git a/src/backend/utils/init/miscinit.c b/src/backend/utils/init/miscinit.c
index fb376a0..8620ee8 100644
--- a/src/backend/utils/init/miscinit.c
+++ b/src/backend/utils/init/miscinit.c
@@ -663,10 +663,11 @@ UnlinkLockFile(int status, Datum filename)
  * filename is the name of the lockfile to create.
  * amPostmaster is used to determine how to encode the output PID.
  * isDDLock and refName are used to determine what error message to produce.
+ * socketPath is the path to the Unix socket we want to lock.
  */
 static void
 CreateLockFile(const char *filename, bool amPostmaster,
-			   bool isDDLock, const char *refName)
+			   bool isDDLock, const char *refName, const char *socketPath)
 {
 	int			fd;
 	char		buffer[MAXPGPATH * 2 + 256];
@@ -892,7 +893,7 @@ CreateLockFile(const char *filename, bool amPostmaster,
 			 (long) MyStartTime,
 			 PostPortNumber,
 #ifdef HAVE_UNIX_SOCKETS
-			 (*UnixSocketDir != '\0') ? UnixSocketDir : DEFAULT_PGSOCKET_DIR
+			(socketPath) ? socketPath : ""
 #else
 			 ""
 #endif
@@ -949,19 +950,20 @@ CreateLockFile(const char *filename, bool amPostmaster,
 void
 CreateDataDirLockFile(bool amPostmaster)
 {
-	CreateLockFile(DIRECTORY_LOCK_FILE, amPostmaster, true, DataDir);
+	CreateLockFile(DIRECTORY_LOCK_FILE, amPostmaster, true, DataDir, NULL);
 }
 
 /*
  * Create a lockfile for the specified Unix socket file.
  */
 void
-CreateSocketLockFile(const char *socketfile, bool amPostmaster)
+CreateSocketLockFile(const char *socketfile, bool amPostmaster,
+					 const char *socketDir)
 {
 	char		lockfile[MAXPGPATH];
 
 	snprintf(lockfile, sizeof(lockfile), "%s.lock", socketfile);
-	CreateLockFile(lockfile, amPostmaster, false, socketfile);
+	CreateLockFile(lockfile, amPostmaster, false, socketfile, socketDir);
 	/* Save name of lockfile for TouchSocketLockFile */
 	strcpy(socketLockFile, lockfile);
 }
@@ -1292,3 +1294,4 @@ pg_bindtextdomain(const char *domain)
 	}
 #endif
 }
+
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 087aaf9..5603ce4 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -207,6 +207,7 @@ static bool check_application_name(char **newval, void **extra, GucSource source
 static void assign_application_name(const char *newval, void *extra);
 static const char *show_unix_socket_permissions(void);
 static const char *show_log_file_mode(void);
+static void assign_unix_socket_directories(const char *newval, void *extra);
 
 static char *config_enum_get_options(struct config_enum * record,
 						const char *prefix, const char *suffix,
@@ -2895,14 +2896,18 @@ static struct config_string ConfigureNamesString[] =
 	},
 
 	{
-		{"unix_socket_directory", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
-			gettext_noop("Sets the directory where the Unix-domain socket will be created."),
-			NULL,
+		{"unix_socket_directories", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
+			gettext_noop("Sets the directories where the Unix-domain socket will be created."),
+			gettext_noop("Directories are separated by \",\"."),
 			GUC_SUPERUSER_ONLY
 		},
-		&UnixSocketDir,
+		&UnixSocketDirs,
+#ifdef HAVE_UNIX_SOCKETS
+		DEFAULT_PGSOCKET_DIR,
+#else
 		"",
-		check_canonical_path, NULL, NULL
+#endif
+		NULL, assign_unix_socket_directories, NULL
 	},
 
 	{
@@ -8759,4 +8764,34 @@ show_log_file_mode(void)
 	return buf;
 }
 
+static void
+assign_unix_socket_directories(const char *newval, void *extra)
+{
+#ifdef HAVE_UNIX_SOCKETS
+	char	   *rawSocketsString;
+	ListCell   *l;
+
+	/* Clean previous UnixSocketDirList list if not empty */
+	if (UnixSocketDirList)
+	{
+		list_free(UnixSocketDirList);
+		UnixSocketDirList = NIL;
+	}
+
+	/* Need a modifiable copy of value */
+	rawSocketsString = pstrdup(newval);
+
+	/* Parse string into list of directories */
+	if (!SplitDirectoriesString(rawSocketsString, ',', &UnixSocketDirList))
+	{
+		/* syntax error in list */
+		ereport(FATAL,
+			   (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+						errmsg("invalid list syntax for \"unix_socket_directories\"")));
+	}
+
+	pfree(rawSocketsString);
+#endif
+}
+
 #include "guc-file.c"
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index fa75d00..42b5e40 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -65,7 +65,8 @@
 # Note:  Increasing max_connections costs ~400 bytes of shared memory per
 # connection slot, plus lock space (see max_locks_per_transaction).
 #superuser_reserved_connections = 3	# (change requires restart)
-#unix_socket_directory = ''		# (change requires restart)
+#unix_socket_directories = ''		# comma-separated list of directories,
+					# (change requires restart)
 #unix_socket_group = ''			# (change requires restart)
 #unix_socket_permissions = 0777		# begin with 0 to use octal notation
 					# (change requires restart)
diff --git a/src/bin/pg_ctl/pg_ctl.c b/src/bin/pg_ctl/pg_ctl.c
index 72fc4c1..af8d8b2 100644
--- a/src/bin/pg_ctl/pg_ctl.c
+++ b/src/bin/pg_ctl/pg_ctl.c
@@ -521,7 +521,7 @@ test_postmaster_connection(bool do_checkpoint)
 						hostaddr = optlines[LOCK_FILE_LINE_LISTEN_ADDR - 1];
 
 						/*
-						 * While unix_socket_directory can accept relative
+						 * While unix_socket_directories can accept relative
 						 * directories, libpq's host parameter must have a
 						 * leading slash to indicate a socket directory.  So,
 						 * ignore sockdir if it's relative, and try to use TCP
diff --git a/src/include/libpq/libpq.h b/src/include/libpq/libpq.h
index 7083cd8..a79200d 100644
--- a/src/include/libpq/libpq.h
+++ b/src/include/libpq/libpq.h
@@ -45,7 +45,7 @@ typedef struct
  * prototypes for functions in pqcomm.c
  */
 extern int StreamServerPort(int family, char *hostName,
-	unsigned short portNumber, char *unixSocketName, pgsocket ListenSocket[],
+	unsigned short portNumber, char *unixSocketDir, pgsocket ListenSocket[],
 				 int MaxListen);
 extern int	StreamConnection(pgsocket server_fd, Port *port);
 extern void StreamClose(pgsocket sock);
diff --git a/src/include/miscadmin.h b/src/include/miscadmin.h
index b186eed..edfa161 100644
--- a/src/include/miscadmin.h
+++ b/src/include/miscadmin.h
@@ -399,7 +399,8 @@ extern char *local_preload_libraries_string;
 #define LOCK_FILE_LINE_SHMEM_KEY	7
 
 extern void CreateDataDirLockFile(bool amPostmaster);
-extern void CreateSocketLockFile(const char *socketfile, bool amPostmaster);
+extern void CreateSocketLockFile(const char *socketfile, bool amPostmaster,
+								 const char *socketDir);
 extern void TouchSocketLockFile(void);
 extern void AddToDataDirLockFile(int target_line, const char *str);
 extern void ValidatePgVersion(const char *path);
diff --git a/src/include/postmaster/postmaster.h b/src/include/postmaster/postmaster.h
index 7d01d3d..aa549e6 100644
--- a/src/include/postmaster/postmaster.h
+++ b/src/include/postmaster/postmaster.h
@@ -13,13 +13,16 @@
 #ifndef _POSTMASTER_H
 #define _POSTMASTER_H
 
+#include "utils/builtins.h"
+
 /* GUC options */
 extern bool EnableSSL;
 extern int	ReservedBackends;
 extern int	PostPortNumber;
 extern int	Unix_socket_permissions;
 extern char *Unix_socket_group;
-extern char *UnixSocketDir;
+extern char *UnixSocketDirs;
+extern List *UnixSocketDirList;
 extern char *ListenAddresses;
 extern bool ClientAuthInProgress;
 extern int	PreAuthDelay;
diff --git a/src/include/utils/builtins.h b/src/include/utils/builtins.h
index 1063403..adab4ec 100644
--- a/src/include/utils/builtins.h
+++ b/src/include/utils/builtins.h
@@ -752,6 +752,8 @@ extern int	varstr_cmp(char *arg1, int len1, char *arg2, int len2, Oid collid);
 extern List *textToQualifiedNameList(text *textval);
 extern bool SplitIdentifierString(char *rawstring, char separator,
 					  List **namelist);
+extern bool SplitDirectoriesString(char *rawstring, char separator,
+					  List **namelist);
 extern Datum replace_text(PG_FUNCTION_ARGS);
 extern text *replace_text_regexp(text *src_text, void *regexp,
 					text *replace_text, bool glob);