方法 1：按住 control + c 取消本次更新操做composer
➜ ~ brew install composer Updating Homebrew... ^C
按住 control + c 以后命令行会显示 ^C，就表明已经取消了 Updating Homebrew 操做命令行
大概不到 1 秒钟以后就会去执行咱们真正须要的安装操做了code
➜ ~ brew install composer Updating Homebrew... ^C==> Satisfying dependencies ==> Downloading https://getcomposer.org/download/1.7.2/composer.phar ...