private function hasSttyAvailable()
{
if (null !== self::$stty) {
return self::$stty;
}
exec('stty 2>&1', $output, $exitcode);
return self::$stty = $exitcode === 0;
}
/**
* Return a valid Unix shell.
*
* @return string|bool The valid shell name, false in case no valid shell is found
*/
private function getShell()
{
if (null !== self::$shell) {
return self::$shell;
}
self::$shell = false;
if (file_exists('/usr/bin/env')) {
// handle other OSs with bash/zsh/ksh/csh if available to hide the answer
$test = "/usr/bin/env %s -c 'echo OK' 2> /dev/null";
foreach (array('bash', 'zsh', 'ksh', 'csh') as $sh) {
if ('OK' === rtrim(shell_exec(sprintf($test, $sh)))) {
self::$shell = $sh;
break;
}
}
}
return self::$shell;
}
