#include #include #include #include int main(int argc, char* argv[]) { struct timeval tv; fd_set readfs; int STDIN = atoi(argv[1]); tv.tv_sec = 2; tv.tv_usec = 0; FD_ZERO(&readfs); FD_SET(STDIN ,&readfs); //*ptr = 1 << (STDIN % 32); select(STDIN+1, &readfs, NULL, NULL, NULL); if (FD_ISSET(STDIN, &readfs) ) printf("Something pressed\n"); else printf("Time out\n"); printf("%tv %d\n", sizeof(tv) ); printf("readfs %d\n", sizeof(fd_set)); return 0; } .