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