1 files changed, 5 insertions, 2 deletions

diff --git a/prot.c b/prot.c
index 79a88c5..1ffd20c 100644
--- a/prot.c
+++ b/prot.c
@@ -1,12 +1,15 @@
 /* Public domain. */
 
+#include <sys/types.h>
+#include <unistd.h>
+#include <grp.h>
 #include "hasshsgr.h"
 #include "prot.h"
 
-int prot_gid(int gid)
+int prot_gid(gid_t gid)
 {
 #ifdef HASSHORTSETGROUPS
-  short x[2];
+  gid_t x[2];
   x[0] = gid; x[1] = 73; /* catch errors */
   if (setgroups(1,x) == -1) return -1;
 #else