#include "ourhdr.h" int main(void) { printf("fd 0: %s\n", isatty(0) ? "tty" : "not a tty"); printf("fd 1: %s\n", isatty(1) ? "tty" : "not a tty"); printf("fd 2: %s\n", isatty(2) ? "tty" : "not a tty"); exit(0); }