[root@VM_0_7_centos laravel-develop]# composer install
Do not run Composer as root/super user! See https://getcomposer.org/root for details

Fatal error: Uncaught Error: Call to undefined function Symfony\Component\Console\mb_detect_encoding() in /usr/share/php/Symfony/Component/Console/Application.php:1096
Stack trace:

0 /usr/share/php/Symfony/Component/Console/Application.php(650): Symfony\Component\Console\Application->stringWidth(' [Composer\Exc...')

1 /usr/share/php/Symfony/Component/Console/Application.php(131): Symfony\Component\Console\Application->renderException(Object(Composer\Exception\NoSslException), Object(Symfony\Component\Console\Output\StreamOutput))

2 /usr/share/php/Composer/Console/Application.php(100): Symfony\Component\Console\Application->run(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))

3 /usr/bin/composer(55): Composer\Console\Application->run(NULL, Object(Symfony\Component\Console\Output\ConsoleOutput))

4 {main}

thrown in /usr/share/php/Symfony/Component/Console/Application.php on line 1096