getgrent.3: Note glibc 2.22 changes for feature test macro requirements

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>

diff --git a/man3/getgrent.3 b/man3/getgrent.3
index 2ffe6483d8b084c03ba4335c9c431a09a635ef67..5aee88d5e957dedf6b7ec7da89b460788abc8c6c 100644 (file)
--- a/man3/getgrent.3
+++ b/man3/getgrent.3
@@ -60,10 +60,16 @@ _XOPEN_SOURCE\ >=\ 500
 .BR getgrent (),
 .BR endgrent ():
 .RS 4
-_XOPEN_SOURCE\ >=\ 500
-.\"    || _XOPEN_SOURCE\ &&\ _XOPEN_SOURCE_EXTENDED
-    || /* Since glibc 2.12: */ _POSIX_C_SOURCE\ >=\ 200809L
-    || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
+Since glibc 2.22:
+    _XOPEN_SOURCE\ >=\ 500 ||
+.\"        || _XOPEN_SOURCE\ &&\ _XOPEN_SOURCE_EXTENDED
+        _DEFAULT_SOURCE
+.br
+Glibc 2.21 and earlier    
+    _XOPEN_SOURCE\ >=\ 500
+.\"        || _XOPEN_SOURCE\ &&\ _XOPEN_SOURCE_EXTENDED
+        || /* Since glibc 2.12: */ _POSIX_C_SOURCE\ >=\ 200809L
+        || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
 .RE
 .PD
 .ad b