翻译_bash:bash命令行下如何引用历史命令的参数

本文来自stackoverflow一个问答，提及的技巧似乎以前在网上或资料上未见过，特译之。

原文地址:http://stackoverflow.com/questions/4009412/bash-how-to-use-arguments-from-previous-command

译文:

问:

I know that ESC DOT gives you the last argument of the last command.

But I'm interested in first argument of the last command. Is there a key binding to do so?

On the same lines, is there a generic way of getting nth argument from last command. (I know that in a bash script you can use $0, $1 etc., but these don't work on commandline)

Also, what about iterating through 0th argument of previous commands, like we can do with last argument by continuously pressing ESC DOT

我知道ESC-.(即ALT-.)可以引用上条命名的最后一个参数。

但如果感兴趣的是第一个参数，是否有一个快捷键来引用呢？

在同一行，是否有一个一般的方法来获得上条命令的第N条参数(我知道bash脚本中你可以使用$0,$1...，但在命令行下不起作用)

此外，如果是像ESC-.(ALT-.)那样引用上条命令的最后一个参数，怎样去逐条访问每条过去命令的第0个参数呢？

答:

Just as M-. (meta-dot or esc-dot or alt-dot) is the readline function yank-last-arg, M-C-y (meta-control-y or esc-ctrl-y or ctrl-alt-y) is the readline function yank-nth-arg. Without specifying n, it yanks the first argument of the previous command.

就像 M-.(meta-.,或esc-.或alt-.)是调用readline函数 yank-last-arg一样，M-C-y(meta-ctrl-y或esc-ctrl-y或alt-ctrl-y)是调用readline函数yank-nth-arg。不指定n,函数黏贴(yank)过去命令的第一个参数。

To specify an argument, press Escape and a number or hold Alt and press a number. You can do Alt--to begin specifying a negative number then release Alt and press the digit (this will count from the end of the list of arguments.

  为了指定一个参数，可以按Esc然后接一个数字或同时按住alt和一个数字。你可以按alt--来开始指定一个负数，然后松开alt再按一个数字,这将从过去命令的参数的从后向前计数的参数。

Example:

例子:

Enter the following command

输入下面命令

$ echo a b c d e f ga b c d e f g

Now at the next prompt, type echo (with a following space), then

Press Alt-Ctrl-y and you'll now see:

现在在下个提示符下，输入echo(跟随一个空格),接着按alt-ctrl-y然后你可以看到:

$ echo a

without pressing Enter yet, do the following
不回车，接着做:
Press Alt-3 Alt-Ctrl-y
Press Alt-- 2 Alt-Ctrl-y
Now you will see:
现在你看到：
$ echo ace

By the way, you could have put the echo on the line by selecting argument 0:

顺便说，你可以把像引用参数0一样输入echo:

Press Alt-0 Alt-Ctrl-y

To answer the question you added to your original:

现在回答你的补充问题:

You can press Alt-0 then repeatedly press Alt-. to step through the previous commands (arg 0). Similarly Alt-- then repeating Alt-. would allow you to step through the previous next-to-last arguments.

你能按alt-o然后重复的按alt-.来访问过去每一个命令，类似的，alt--然后alt-.允许你访问过去命令的每一个倒数第二个参数。

If there is no appropriate argument on a particular line in history, the bell will be rung.

如果历史命令上没有恰当的参数，将响铃提示.

If there is a particular combination you use frequently, you can define a macro so one keystroke will perform it. This example will recall the second argument from previous commands by pressing Alt-Shift-Y. You could choose any available keystroke you prefer instead of this one. You can press it repeatedly to step through previous ones.

如果有一个你经常使用的特定的组合，你可以定义一个宏，这样可以一键执行。比如下面的例子可以重复调用过去命令的第二个参数通过按alt-shift-y.你可以选择任何你喜欢的按键。你可以重复按来访问过去的参数。

To try it out, enter the macro at a Bash prompt:

现在来试试，在bash提示符下输入宏:

bind '"\eY": "\e2\e."'

To make it persistent, add this line to your ~/.inputrc file:

如果要永久化，则把下面的这行加入你的~/.inputrc文件:

"\eY": "\e2\e."

Unfortunately, this doesn't seem to work for arg 0 or negative argument numbers

不幸的是，这似乎对参数0或负参数不起作用。