问题描述
我经常在运行cd命令后运行ls命令。如何为此操作创建别名(如cs)？
最佳解决办法
来自Bash Tips and Tricks: ‘cd’ with style：
Finally, I want to show you how to write your own custom replacement for the ‘cd’ command.
Do you find yourself always typing the same thing upon changing into a directory? You probably at least list the files there every time, perhaps so much that your hands automatically type ‘ls’ after every ‘cd’.
Well, by trying every way I could think of, it turns out there’s only one way to properly accomplish the goal we’re seeking. We have to create a shell function.
Shell functions are part of shell programming. Like in compiled programming languages, functions provide a sort of procedural modularizability. One can create a generic function to perform an often-used bit of logic or computation with different parameters. In this case, the parameter is the current working directory.
Here’s a simple one:
function cs () { cd $1 ls }
正如@geirha正确指出的那样，如果您尝试切换到名称中包含空格的目录，则上述功能将失败：
$ cs A\ B/
-bash: cd: A: No such file or directory
<current directory listing>
您应该使用以下函数：
function cs () {
cd "$@" && ls
}
将该代码添加到~/.bashrc后，您应该可以这样做：
hello@world:~$ cs Documents/
example.pdf tunafish.odt
hello@world:~/Documents$
次佳解决办法
您可以在bash中使用builtin命令：
function cd() {
new_directory="$*";
if [ $# -eq 0 ]; then
new_directory=${HOME};
fi;
builtin cd "${new_directory}" && ls
}
第三种解决办法
使用函数而不是别名：
cs() { cd "$1" && ls; }
第四种办法
感谢Florian Diesch获取使用功能的提示。我不能使用cs作为名称，因为csound包中有一个cs命令，所以我使用了lc。
我把它添加到~/.bash_aliases(nano ~/.bash_aliases)：
function lc () {
cd $1;
ls
}
终端需要为reset才能生效。