Mid id.c /^main(argc, argv)$/ current id.c /^current()$/ err id.c /^err(fmt, va_alist)$/ gcmp id.c /^gcmp(a, b)$/ sgroup id.c /^sgroup(pw)$/ ugroup id.c /^ugroup(pw)$/ usage id.c /^usage()$/ user id.c /^user(pw)$/ who id.c /^who(u)$/