Mac添加PATH环境变量

用常规方法安装好npm之后,

$ npm --version
bash: npm: commmand not found

以为是没有安装后，换用brewhomehttps://brew.sh/index_zh-cn.html进行安装

$ brew --version

依旧 command not found

注意到，warning:

==> Cleaning up /Library/Caches/Homebrew...
==> Migrating /Library/Caches/Homebrew to /Users/htwt/Library/Caches/Homebrew...
==> Deleting /Library/Caches/Homebrew...
Already up-to-date.
Warning: /usr/local/bin is not in your PATH.
==> Installation successful!

$ echo $PATH
/usr/bin:/bin:/usr/sbin:/sbin:/Applications/Emacs.app/Contents/MacOS/bin-x86_64-10_9:/Applications/Emacs.app/Contents/MacOS/libexec-x86_64-10_9

需要手动添加一个PATH

$ export PATH=/usr/local/bin:$PATH
$ echo $PATH
/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:/Applications/Emacs.app/Contents/MacOS/bin-x86_64-10_9:/Applications/Emacs.app/Contents/MacOS/libexec-x86_64-10_9

现在npm, brew都可以直接用了

另外一种方法是修改 ~/.bash_profile文件

# export local bin
export PATH=/usr/local/bin:$PATH

接着,
$ source ~/.bash_profile

但接着又出现了新的问题, 每次重启emacs, 重启terminal之后, 都需要 source ~/.bash_profile

解决方法如下:
1, 搞清楚用的是哪个shell,
$ echo $SHELL
/bin/bash

2, zsh对应~/.zshrc, bash对应~/.bashrc,
添加入source ~/.bash_profile

这样的话，在每次打开shell时候都能自动加载了

ref: