code: function exec(opts, cmd, extra) {
      extra = extra || {};
      var silent = (extra.silent !== false); // Silent, unless explicitly passed `false`
      if ( opts.noWrite && extra.always !== true) {
        grunt.log.writeln('DRY-RUN: would exec: ' + cmd);
      } else {
        grunt.verbose.writeln('Running: ' + cmd);
        var result = shell.exec(cmd, {silent: silent});
  
        // grunt.verbose.writeln('exec(' + cmd + ') returning code ' + result.code +
        //   ', result: ' + result.stdout);
        if (extra.checkResultCode !== false && result.code !== 0) {
          grunt.fail.warn('exec(' + cmd + ') failed with code ' + result.code +
            ':\n' + result.stdout);
        }else{
          return result;
        }
      }
    }
docs: Execute shell command (synchronous).