isatty.c raw

   1  #include <unistd.h>
   2  #include <errno.h>
   3  #include <sys/ioctl.h>
   4  #include "syscall.h"
   5  
   6  int isatty(int fd)
   7  {
   8  	struct winsize wsz;
   9  	unsigned long r = syscall(SYS_ioctl, fd, TIOCGWINSZ, &wsz);
  10  	if (r == 0) return 1;
  11  	if (errno != EBADF) errno = ENOTTY;
  12  	return 0;
  13  }
  14