ref: 3b65e3d6975fed9177cd827346e56f708c3ce6c1 dir: /sys/src/ape/lib/ap/plan9/setgid.c/
#include <sys/types.h> #include <unistd.h> #include <errno.h> /* * BUG: never works */ int setgid(gid_t) { errno = EPERM; return -1; }