regex_internal.h: define __attribute_warn_unused_result__

[gnulib.git] / doc / posix-functions / getgroups.texi

diff --git a/doc/posix-functions/getgroups.texi b/doc/posix-functions/getgroups.texi
index 951705e..0e838f7 100644 (file)
--- a/doc/posix-functions/getgroups.texi
+++ b/doc/posix-functions/getgroups.texi
@@ -12,10 +12,23 @@ Portability problems fixed by Gnulib:
 This function is missing on some platforms:
 mingw.
 @item
-On Ultrix 4.3, @code{getgroups (0, 0)} always fails.  See macro
+On some platforms, this function fails to reject a negative count,
+even though that is less than the size that would be returned:
+FreeBSD 7.2.
+@item
+On Ultrix 4.3, @code{getgroups (0, NULL)} always fails.  See macro
 @samp{AC_FUNC_GETGROUPS}.
+@item
+On very old systems, this function operated on an array of @samp{int},
+even though that was a different size than an array of @samp{gid_t}.
 @end itemize
 
 Portability problems not fixed by Gnulib:
 @itemize
+@item
+It is unspecified whether the effective group id will be included in
+the returned list, nor whether the list will be sorted in any
+particular order.  For that matter, some platforms include the
+effective group id twice, if it is also a member of the current
+supplemental group ids.
 @end itemize