gistfile1.php

<?php

/**
 * @file
 */

function ssh_drush_command() {
  $items['ssh-blah'] = array(
    'description' => '',
    'arguments' => array(
      'site-alias' => 'A site alias',
    ),
    'options' => array(
    ),
    'examples' => array(
    ),
    'bootstrap' => DRUSH_BOOTSTRAP_DRUSH,
  );
  return $items;
}

/**
 * Command callback.
 */
function drush_ssh_blah($alias) {
  $site = drush_sitealias_get_record($alias);
  $hostname = isset($site['remote-host']) ? drush_escapeshellarg($site['remote-host'], "LOCAL") : null;
  $username = isset($site['remote-user']) ? drush_escapeshellarg($site['remote-user'], "LOCAL") . "@" : '';
  $ssh_options = isset($site['ssh-options']) ? $site['ssh-options'] : drush_get_option('ssh-options', "-o PasswordAuthentication=no");

  if (!is_null($hostname)) {
    $cmd = "ssh " . $ssh_options . " " . $username . $hostname . " " . drush_escapeshellarg($command, "LOCAL");
  }
  proc_close(proc_open($cmd, array(0 => STDIN, 1 => STDOUT, 2 => STDERR), $pipes));
}