#include <grp.h>

#define T(t) (t*)0;

#define F(t,n) {t *y = &x.;;}

static void f()

{

T(gid_t)

T(size_t)

{

struct group x;

F(char*, gr_name)

F(gid_t, gr_gid)

F(char**, gr_mem)

}

{void(*p)(void) = endgrent;}

{struct group*(*p)(void) = getgrent;}

{struct group*(*p)(gid_t) = getgrgid;}

{int(*p)(gid_t,struct group*,char*,size_t,struct group**) = getgrgid_r;}

{struct group*(*p)(const char*) = getgrnam;}

{int(*p)(const char*,struct group*,char*,size_t,struct group**) = getgrnam_r;}

#ifdef _XOPEN_SOURCE

{void(*p)(void) = setgrent;}

#endif

}