检测是否安装了自制程序包

本文介绍了检测是否安装了自制程序包的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我将要编写一个Shell脚本来检测系统中是否安装了几个自制程序包.有没有一种方法可以使用brew命令来实现这一目标?

I'm about to write a shell script to detect if several homebrew packages are installed in the system. Is there a way to use a brew command to achieve that?

我尝试使用brew install <formula> --dry-run的退出代码.但这会构建缺少的软件包.

I tried using the exit code of brew install <formula> --dry-run. But this builds the package if it is missing.

推荐答案

您可以使用

brew ls --versions myformula

输出相应公式的已安装版本.如果未安装该公式，则输出将为空.

to output the installed versions of the respective formula. If the formula is not installed, the output will be empty.

使用brew update可获得的最新版本的自制软件时，只需运行以下命令即可(感谢Slaven):

When using a recent versions of homebrew, which you can get with brew update, you can just run this (thanks Slaven):

if brew ls --versions myformula > /dev/null; then # The package is installed else # The package is not installed fi

也就是说，最好检查一下该工具是否存在，而不仅仅是检查各自的自制软件包(例如，通过在$PATH中搜索可执行文件).人们倾向于在实践中以大量方式安装工具，而自制软件只是其中一种.

That said, it is probably a good idea to check for the existence of the tool at all and not just checking for the respective homebrew package (e.g. by searching for the executable in the $PATH). People tend to install tools in a rather large amount of ways in practice, with homebrew being just one of them.