How can I solve "laravel/horizon v1.1.0 requires ext-pcntl * -> the requested PHP extension pcntl is missing from your system"?

When I run composer install on command promp, there exist error like this :

  Problem 1
    - Installation request for laravel/horizon v1.1.0 -> satisfiable by laravel/horizon[v1.1.0].
    - laravel/horizon v1.1.0 requires ext-pcntl * -> the requested PHP extension pcntl is missing from your system.

  To enable extensions, verify that they are enabled in your .ini files:
    - C:\xampp-7.1\php\php.ini
  You can also run `php --ini` inside terminal to see which files are used by PHP in CLI mode.

How can I solve this error?

Solution 1:

Run composer with the --ignore-platform-reqs option and specify pcntl and posix

composer install --ignore-platform-reqs

Solution 2:

As per the accepted answer, but you can add this to your composer.json so that you don't have to run --ignore-platform-reqs all the time

"config": {
  "platform": {
    "ext-pcntl": "8.0",
    "ext-posix": "8.0"
  }
}

Solution 3:

install horizon this way :

composer require laravel/horizon --ignore-platform-reqs

then run

php artisan horizon:install

Solution 4:

pcntl extension is not supported on Windows. (based on your XAMPP information)

Please see these github issues on laravel/horizon page #131, #78.

I suggest you use Laravel Homestead on your Windows system, It is easy to setup and will save you from many of the similar problems in future.

Solution 5:

If you are using docker based on a Unix image you can add it with the docker utility:

docker-php-ext-install pcntl

You can then confirm that this extension is installed and enabled inside of your container:

?> php -i | grep pcntl
/usr/local/etc/php/conf.d/docker-php-ext-pcntl.ini,
pcntl
pcntl support => enabled