code: function bash(pattern, options, cb) {
    if (!isGlob(pattern)) {
      return nonGlob(pattern, options, cb);
    }
  
    if (typeof options === 'function') {
      cb = options;
      options = undefined;
    }
  
    var opts = extend({cwd: process.cwd()}, options);
  
    fs.stat(opts.cwd, function(err, stat) {
      if (err) {
        cb(handleError(err, pattern, opts));
        return;
      }
  
      if (!stat.isDirectory()) {
        cb(new Error('cwd is not a directory: ' + opts.cwd));
        return;
      }
  
      var cp = spawn(bashPath, cmd(pattern, options), options);
      var buf = new Buffer(0);
  
      cp.stdout.on('data', function(data) {
        emitMatches(data.toString(), pattern, options);
        buf = Buffer.concat([buf, data]);
      });
  
      cp.stderr.on('data', function(data) {
        cb(handleError(data.toString(), pattern, options));
      });
  
      cp.on('close', function(code) {
        cb(code, getFiles(buf.toString(), pattern, options));
      });
    });
  }
docs: Base bash function