ref: ad6e6444f9c1bf3a2d65c67ab8f4f48ac6468104 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 gid) { errno = EPERM; return -1; }