Drush dl이 PHP 7 및 우분투 16.04에서 작동하지 않습니다

내가하려고 할 때 :

drush dl drupal-8

다음과 같은 오류가 발생합니다.

PHP Fatal error:  Uncaught Error: Call to undefined function Drush\UpdateService\simplexml_load_file() in /home/alexander/.config/composer/vendor/drush/drush/lib/Drush/UpdateService/Project.php:74
Stack trace:
#0 /home/alexander/.config/composer/vendor/drush/drush/lib/Drush/UpdateService/ReleaseInfo.php(64): Drush\UpdateService\Project::getInstance(Array, 86400)
#1 /home/alexander/.config/composer/vendor/drush/drush/lib/Drush/UpdateService/ReleaseInfo.php(122): Drush\UpdateService\ReleaseInfo->get(Array)
#2 /home/alexander/.config/composer/vendor/drush/drush/commands/pm/download.pm.inc(111): Drush\UpdateService\ReleaseInfo->selectReleaseBasedOnStrategy(Array, '', 'auto', false, NULL)
#3 /home/alexander/.config/composer/vendor/drush/drush/includes/command.inc(366): drush_pm_download()
#4 /home/alexander/.config/composer/vendor/drush/drush/includes/command.inc(217): _drush_invoke_hooks(Array, Array)
#5 /home/alexander/.config/composer/vendor/drush/drush/includes/command.inc(185): drush_command()
#6 /home/alexander/.config/compos in /home/alexander/.config/composer/vendor/drush/drush/lib/Drush/UpdateService/Project.php on line 74
Drush command terminated abnormally due to an unrecoverable error.

drush cc, drush status와 같은 다른 명령도 작동합니다.

Drush 상태 출력은 다음과 같습니다.

 PHP executable         :  /usr/bin/php
 PHP configuration      :  /etc/php/7.0/cli/php.ini
 PHP OS                 :  Linux
 Drush script           :  /home/alexander/.config/composer/vendor/drush/drush/drush.php
 Drush version          :  8.1.2
 Drush temp directory   :  /tmp
 Drush configuration    :
 Drush alias files      :

simplexml 확장명없이 PHP를 설치 / 구성한 것처럼 들립니다.

다음과 같이 apt-get과 함께 php7.0-xml 패키지를 설치하십시오.

sudo apt-get install php-xml

또한 UI 설치 프로그램을 확인하십시오.이 누락 된 경우 Drupal을 설치 / 사용하는 다른 확장 링크 mbstring, gd 등이 누락되었을 수 있습니다.