ref: 07c8c2c838256ea0b3b9dd6d5a70ba32ff3bafab dir: /sys/src/ape/lib/ap/plan9/setuid.c/
#include <sys/types.h> #include <unistd.h> #include <errno.h> /* * BUG: never works */ int setuid(uid_t) { errno = EPERM; return -1; }