Clarify the return value of getenv.
Index: lib/libc/stdlib/getenv.3
===================================================================
RCS file: /cvsroot/OpenBSD/src/lib/libc/stdlib/getenv.3,v
retrieving revision 1.19
diff -u -p -r1.19 getenv.3
--- lib/libc/stdlib/getenv.3 5 Jun 2013 03:39:23 -0000 1.19
+++ lib/libc/stdlib/getenv.3 21 Apr 2014 01:37:57 -0000
@@ -102,11 +102,13 @@ function deletes all instances of the va
.Fa name
from the list.
.Sh RETURN VALUES
-These functions
-return zero if successful; otherwise the global variable
-.Va errno
-is set to indicate the error and \-1 is returned.
+.Rv -std putenv setenv unsetenv
.Pp
+The
+.Fn getenv
+function returns a pointer to the requested value, or
+.Dv NULL
+if it could not be found.
If
.Fn getenv
is successful, the string returned should be considered read-only.