何为 PATH？
PATH 路径是环境变量，和 Windows 系统类似，是可执行命令文件的存放路径。
当你在命令行输入一个 ls 命令时，系统会在当前工作目录以及 PATH 的路径中依次寻找，找到的话执行，找不到的话返回 command not found: ls。
PATH 路径可以通过 echo $PATH 查看，
或者 env|grep PATH。
修改 PATH
添加
-
临时添加
usr/local/bin直接在终端输入命令
PATH=$PATH:/usr/local/bin更改在当前会话有效，退出本次会话后则失效
-
永久添加
usr/local/bin修改
.bashrc文件添加一句：
export PATH=$PATH:/usr/local/bin
删除
-
临时删除
直接在终端输入命令
PATH=......为除去不想要的路径的其他所有路径 -
永久删除
- 将上面的临时命令放入
.bashrc中：echo PATH=...
或者在.bashrc文件末尾添加以下代码：
### remove unnecessary Win PATHs # This can prevent extension-less commands from bleeding into BASH. # (eg. "ng" would execute the Win bin if "@angular/cli" wasn't installed on Linux.) # function path_remove { # Delete path by parts so we can never accidentally remove sub paths PATH=${PATH//":$1:"/":"} # delete any instances in the middle PATH=${PATH/#"$1:"/} # delete any instance at the beginning PATH=${PATH/%":$1"/} # delete any instance in the at the end } path_remove '/mnt/c/Users/me/AppData/Roaming/npm' path_remove '/mnt/c/Users/me/AppData/Local/Yarn/bin' path_remove '/mnt/c/Program Files (x86)/Yarn/bin' path_remove '/mnt/c/Program Files/Git' path_remove '/mnt/c/Program Files/Git/cmd' path_remove '/mnt/c/Program Files/nodejs' path_remove '/mnt/c/OpenSSL-Win32/bin' path_remove '/mnt/c/Program Files (x86)/Python27' - 将上面的临时命令放入
