$ ps
  PID TTY          TIME CMD
  265 pts/5    00:00:00 bash
 2969 pts/5    00:00:00 bash
 6679 pts/5    00:00:00 ps
$ echo hihi >/tmp/hi
Broken pipe
$ ps
  PID TTY          TIME CMD
  265 pts/5    00:00:00 bash
32561 pts/5    00:00:00 ps

#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <string.h>
#include <fcntl.h>

int main(int argc, char **argv) { 
        int fd;

        fd = open(argv[1], O_RDONLY);
        printf("%d\n", lseek(fd, 0, SEEK_SET));
}