How to check if a shell command exists from PHP

Question

I need something like this in php:

If (!command_exists(\'makemiracle\')) {
  print \'no miracles\';
  return FALSE;
}
else {
  // safely call the command kno         


        

Answer 1

Based on @xdazz answer, works on Windows and Linux. Should also work on MacOSX too, since it's unix.

function is_windows() {
  return strtoupper(substr(PHP_OS, 0, 3)) === 'WIN';
}

function command_exists($command) {
    $test = is_windows() ? "where" : "which";
    return is_executable(trim(shell_exec("$test $command")));
}