Erro ao no comando composer

miguelangelo1973
(usa Linux Mint)

Enviado em 12/12/2019 - 00:46h

Olá alguém pode me ajudar? Instalei o Xampp no Linux e o Composer, eles estão rodando mas ao usar o comando para criar um projeto com Laravel, aparece esse erro:

sudo composer create-project --prefer-dist laravel/laravel teste
[sudo] senha para miguel:
Do not run Composer as root/super user! See https://getcomposer.org/root for details
Installing laravel/laravel (v6.5.2)
- Installing laravel/laravel (v6.5.2): Loading from cache
Created project in teste
> @php -r "file_exists('.env') || copy('.env.example', '.env');"
Loading composer repositories with package information
Updating dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.

Problem 1
- laravel/framework v6.7.0 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
- laravel/framework v6.6.2 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
- laravel/framework v6.6.1 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
- laravel/framework v6.6.0 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
- laravel/framework v6.5.2 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
- laravel/framework v6.5.1 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
- laravel/framework v6.5.0 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
- laravel/framework v6.4.1 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
- laravel/framework v6.4.0 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
- laravel/framework v6.3.0 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
- laravel/framework v6.2.0 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
- laravel/framework 6.x-dev requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
- Installation request for laravel/framework ^6.2 -> satisfiable by laravel/framework[6.x-dev, v6.2.0, v6.3.0, v6.4.0, v6.4.1, v6.5.0, v6.5.1, v6.5.2, v6.6.0, v6.6.1, v6.6.2, v6.7.0].

To enable extensions, verify that they are enabled in your .ini files:
- /etc/php/7.2/cli/php.ini
- /etc/php/7.2/cli/conf.d/10-opcache.ini
- /etc/php/7.2/cli/conf.d/10-pdo.ini
- /etc/php/7.2/cli/conf.d/20-calendar.ini
- /etc/php/7.2/cli/conf.d/20-ctype.ini
- /etc/php/7.2/cli/conf.d/20-exif.ini
- /etc/php/7.2/cli/conf.d/20-fileinfo.ini
- /etc/php/7.2/cli/conf.d/20-ftp.ini
- /etc/php/7.2/cli/conf.d/20-gettext.ini
- /etc/php/7.2/cli/conf.d/20-iconv.ini
- /etc/php/7.2/cli/conf.d/20-json.ini
- /etc/php/7.2/cli/conf.d/20-phar.ini
- /etc/php/7.2/cli/conf.d/20-posix.ini
- /etc/php/7.2/cli/conf.d/20-readline.ini
- /etc/php/7.2/cli/conf.d/20-shmop.ini
- /etc/php/7.2/cli/conf.d/20-sockets.ini
- /etc/php/7.2/cli/conf.d/20-sysvmsg.ini
- /etc/php/7.2/cli/conf.d/20-sysvsem.ini
- /etc/php/7.2/cli/conf.d/20-sysvshm.ini
- /etc/php/7.2/cli/conf.d/20-tokenizer.ini
You can also run `php --ini` inside terminal to see which files are used by PHP in CLI mode.