fix compile failure: legacy cuserid needs to define feature test

diff --git a/src/misc/cuserid.c b/src/misc/cuserid.c
index 8ad0b9f3b90377080ef92cf872827723abd3c2eb..4e78798ded26b09992bb69c4383447a805ae2ab9 100644 (file)
--- a/src/misc/cuserid.c
+++ b/src/misc/cuserid.c
@@ -1,3 +1,4 @@
+#define _GNU_SOURCE
 #include <pwd.h>
 #include <stdio.h>
 #include <unistd.h>