composer require第三方包的时候，发生如下错误

D:\study\shop>composer require laravel/jetstream
Using version ^1.6 for laravel/jetstream
./composer.json has been updated
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/horizon v5.4.0 requires ext-pcntl * -> the requested PHP extension pcntl is missing from your system.
    - laravel/horizon v5.4.0 requires ext-pcntl * -> the requested PHP extension pcntl is missing from your system.
    - laravel/horizon v5.4.0 requires ext-pcntl * -> the requested PHP extension pcntl is missing from your system.
    - Installation request for laravel/horizon (locked at v5.4.0, required as ^5.4) -> satisfiable by laravel/horizon[v5.4.0].

  To enable extensions, verify that they are enabled in your .ini files:
    - D:\phpstudy_pro\Extensions\php\php7.4.3nts\php.ini
  You can also run `php --ini` inside terminal to see which files are used by PHP in CLI mode.

Installation failed, reverting ./composer.json to its original content.

解决方法

带上引包的时候后面加上--ignore-platform-reqs

命令说明

—ignore-platform-reqs: ignore all platform requirements (php, hhvm, lib- and ext-) and force the installation even if the local machine does not fulfill these. See also the platform config option

忽略所有平台要求（php，hhvm，lib- 和ext- ）并强制安装，即使本地计算机不满足这些要求