diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml
index 8ef5387..c76fe60 100644
--- a/doc/src/sgml/ref/psql-ref.sgml
+++ b/doc/src/sgml/ref/psql-ref.sgml
@@ -2236,6 +2236,24 @@ lo_import 152801
+ \setenv [ name [ value ] ]
+
+
+
+ Sets the environment variable name to value, or if the
+ value is
+ not supplied, unsets the environment variable. Example:
+
+foo=> \setenv PAGER less
+foo=> \setenv LESS -imx4F
+
+
+
+
+
+
\sf[+] function_description>
diff --git a/src/bin/psql/command.c b/src/bin/psql/command.c
index 2c38902..797317a 100644
--- a/src/bin/psql/command.c
+++ b/src/bin/psql/command.c
@@ -1104,6 +1104,50 @@ exec_command(const char *cmd,
free(opt0);
}
+
+ /* \setenv -- set environment command */
+ else if (strcmp(cmd, "setenv") == 0)
+ {
+ char *envvar = psql_scan_slash_option(scan_state,
+ OT_NORMAL, NULL, false);
+ char *envval = psql_scan_slash_option(scan_state,
+ OT_NORMAL, NULL, false);
+
+ if (!envvar)
+ {
+ psql_error("\\%s: missing required argument\n", cmd);
+ success = false;
+ }
+ else if (!envval)
+ {
+ /* No argument - unset the environment variable */
+ unsetenv(envvar);
+ success = true;
+ }
+ else
+ {
+ /* Set variable to the vakue of the next argument */
+ int len = strlen(envvar) + strlen(envval) + 1;
+ char *newval = malloc(len + 1);
+
+ if (!newval)
+ {
+ psql_error("out of memory\n");
+ exit(EXIT_FAILURE);
+ }
+ snprintf(newval, len+1, "%s=%s", envvar, envval);
+ putenv(newval);
+ success = true;
+ /*
+ * Do not free newval here, it will screw up the environment
+ * if you do. See putenv man page for details. That means we
+ * leak a bit of memory here, but not enough to worry about.
+ */
+ }
+ free(envvar);
+ free(envval);
+ }
+
/* \sf -- show a function's source code */
else if (strcmp(cmd, "sf") == 0 || strcmp(cmd, "sf+") == 0)
{