ref: edd3be53e7dc7b3362b4f1af86788a8fcae8b4fb 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; }