bash 检测是否安装了自制软件包
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/20802320/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Detect if homebrew package is installed
提问by iltempo
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?
我即将编写一个 shell 脚本来检测系统中是否安装了多个自制程序包。有没有办法使用 brew 命令来实现这一点？
I tried using the exit code of brew install <formula> --dry-run. But this builds the package if it is missing.
我尝试使用brew install <formula> --dry-run. 但是如果它丢失，这会构建包。
回答by Holger Just
You can use
您可以使用
brew ls --versions myformula
to output the installed versions of the respective formula. If the formula is not installed, the output will be empty.
输出相应公式的已安装版本。如果未安装公式，则输出将为空。
When using a recent versions of homebrew, which you can get with brew update, you can just run this (thanks Slaven):
当使用最新版本的自制软件时，你可以使用它brew update，你可以运行这个（感谢 Slaven）：
if brew ls --versions myformula > /dev/null; then
# The package is installed
else
# The package is not installed
fi
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 $PATH). People tend to install tools in a rather large amount of ways in practice, with homebrew being just one of them.
也就是说，检查该工具是否存在可能是一个好主意，而不仅仅是检查相应的自制程序包（例如，通过在 中搜索可执行文件$PATH）。人们在实践中倾向于以相当多的方式安装工具，自制软件只是其中之一。
回答by Johannes Weiss
What about?
关于什么？
for pkg in macvim ngrep other needed packages; do
if brew list -1 | grep -q "^${pkg}$"; then
echo "Package '$pkg' is installed"
else
echo "Package '$pkg' is not installed"
fi
done
回答by timotheecour
# install if we haven't installed any version
brew ls --versions $lib || brew install $lib
# install if we haven't installed latest version
brew outdated $lib || brew install $lib
