PhpBrew\Utils::pipeExecute PHP Method

    public static function pipeExecute($command)
    {
        $proc = proc_open($command, array(array('pipe', 'r'), array('pipe', 'w'), array('pipe', 'w')), $pipes);
        return stream_get_contents($pipes[1]);
    }

 public function check(Build $build)
 {
     $apxs = $build->getVariant('apxs2');
     // trying to find apxs binary in case it wasn't explicitly specified (+apxs variant without path)
     if ($apxs === true) {
         $apxs = Utils::findbin('apxs');
         $this->logger->debug("Found apxs2 binary: {$apxs}");
     }
     if (!is_executable($apxs)) {
         throw new Exception("apxs binary is not executable: {$apxs}");
     }
     // use apxs to check module dir permission
     if ($apxs && ($libdir = trim(Utils::pipeExecute("{$apxs} -q LIBEXECDIR")))) {
         if (false === is_writable($libdir)) {
             throw new Exception("Apache module dir {$libdir} is not writable.\nPlease consider using chmod or sudo.");
         }
     }
     if ($apxs && ($confdir = trim(Utils::pipeExecute("{$apxs} -q SYSCONFDIR")))) {
         if (false === is_writable($confdir)) {
             $msg = array();
             $msg[] = "Apache conf dir {$confdir} is not writable for phpbrew.";
             $msg[] = "Please consider using chmod or sudo: ";
             $msg[] = "    \$ sudo chmod -R og+rw {$confdir}";
             throw new Exception(join("\n", $msg));
         }
     }
 }