ref: b9c1eaa2de919a6c1a323826eba1a9e63e3d149c 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; }