ref: e74a87d537dfd2ed817ba94314df7c517b51d65a dir: /sys/src/ape/lib/ap/plan9/getgroups.c/
#include <sys/types.h> #include <unistd.h> #include <errno.h> int getgroups(int, gid_t*) { errno = EINVAL; return -1; }