ref: 2e1cd4eea3163cc033d0eca6ba5e5fd4efc4a5f2 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; }