void endgrent(void);
void setgrent(void);
+#if defined(_GNU_SOURCE) || defined(_BSD_SOURCE)
+int getgrouplist(const char *, gid_t, gid_t *, int *);
+int setgroups(size_t, const gid_t *);
+int initgroups(const char *, gid_t);
+#endif
+
#ifdef __cplusplus
}
#endif