/* Use editor if stdin and stdout are the same and is a tty */
return (!fstat(0, &st_stdin) &&
!fstat(1, &st_stdout) &&
- isatty(0) &&
+ isatty(0) && isatty(1) &&
st_stdin.st_dev == st_stdout.st_dev &&
st_stdin.st_ino == st_stdout.st_ino &&
st_stdin.st_mode == st_stdout.st_mode);