ref: c9b749da88bb2e6b9ef03ffb0bc7a89aafb4089c dir: /sys/src/ape/lib/ap/plan9/getgroups.c/
#include <sys/types.h> #include <unistd.h> #include <errno.h> int getgroups(int gidsize, gid_t grouplist[]) { errno = EINVAL; return -1; }