-#ifdef __STDC__
-extern struct group *getgrgid(gid_t);
-extern struct group *getgrnam(const char *);
-#ifndef _POSIX_SOURCE
-extern struct group *getgrent(void);
-extern int setgrent(void);
-extern void endgrent(void);
-extern void setgrfile(const char *);
-extern int setgroupent(int);
-#endif
-#else
-extern struct group *getgrgid();
-extern struct group *getgrnam();