ref: baa5bfb2cc12a1dba2be5fff032d1fcf6cee49f7 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; }