diff --git a/libc/include/sys/linux-unistd.h b/libc/include/sys/linux-unistd.h
index d945d87..84ea7c3 100644
--- a/libc/include/sys/linux-unistd.h
+++ b/libc/include/sys/linux-unistd.h
@@ -17,8 +17,8 @@
 gid_t            getgid (void);
 uid_t            geteuid (void);
 gid_t            getegid (void);
-uid_t            getresuid (void);
-gid_t            getresgid (void);
+uid_t            getresuid (uid_t *ruid, uid_t *euid, uid_t *suid);
+gid_t            getresgid (gid_t *rgid, gid_t *egid, gid_t *sgid);
 pid_t            gettid (void);
 ssize_t          readahead (int, off64_t, size_t);
 int              getgroups (int, gid_t *);