Shulou(Shulou.com)06/02 Report--

Today, I will talk to you about the use of efficient Bash skills. Many people may not know much about it. In order to let everyone know more, Xiaobian summarized the following contents for everyone. I hope everyone can gain something according to this article.

This is a Bash tips content, some of the content needs to have some basic knowledge and basic operating ability of Linux

The main content is divided into two parts, one part is about history, the other part is about operation

In our daily use, it is inevitable to use some historical commands or sometimes need to correct historical commands, so how to complete these operations more efficiently?

Historyhistory formatting

First we must think of the history command, history can return a list of previously used commands, like this:

(Tao) ➜ ~ history 10 1 cd myzh 2 cd zsh 3 ls 4 cat zshrc 5 brew info tmux 6 brew install tmux 7 cd .tmux 8 cd tmux 9 cp tmux.conf ~/ 10 mv tmux.conf .tmux.conf

We can conveniently return a fixed number of history records by specifying the numbers later, but we only know the order in which they are used. We want to get more detailed information, such as execution time, so we can do this:

(Tao) ➜ ~ export HISTTIMEFORMAT='%F %T '(Tao) ➜ ~ history 10 1 2016-02-09 15:38:40 cd myzh 2 2016-02-09 15:38:44 cd zsh 3 2016-02-09 15:38:51 ls 4 2016-02-09 15:38:59 cat zshrc 5 2016-02-09 15:39:04 brew info tmux 6 2016-02-09 15:48:13 brew install tmux 7 2016-02-09 15:48:17 cd .tmux 8 2016-02-09 15:49:04 cd tmux 9 2016-02-09 15:49:23 cp tmux.conf ~/ 10 2016-02-09 15:49:47 mv tmux.conf .tmux.conf

By setting the HISTTIMEFORMAT environment variable, the time is displayed in the history.

Use the Specify History command

How do you want to use a piece of history? We use! Serial number, for example, we want to execute the third command, then we enter! 3 is enough:

(Tao) ➜ ~ history 6 1 cd myzh 2 cd zsh 3 ls 4 cat zshrc 5 brew info tmux 6 brew install tmux(Tao) ➜ ~ ! 3(Tao) ➜ ~ lszshrc

Repeat command 3 above. If we want to do the n-th from the bottom, just type it!- n 。

Use the previous command

When we want to use the above command, we have the following four ways:

!- 1 Enter

!! enter

Ctrl + p Enter

Press up arrow Enter

Interested friends can try, these several uses are more common.

Commands that begin with or include certain characters

For example, if we want to use a statement that imports environment variables executed earlier, then I can execute it! export:

#Of course, export can also not lose the whole (Tao)~ ! export (Tao) ➜ ~ export HISTTIMEFORMAT='%F %T '

What if you only remember that xport was included in the command? Of course, that's fine, just add one. You can:

(Tao) ➜ ~ !? xport (Tao)~ export HISTTIMEFORMAT='%F %T ' Get parameters from previous command

For example, touch a file, now want to edit it, then just execute!$ Or!!:$ You can:

(Tao) ➜ ~ touch test.sh (Tao) ➜ ~ vi !$ vi test.sh(Tao) ➜ ~ vi !!:$ vi test.sh

This method only gets the last parameter, so what if we want to get more than just the last parameter? Use!* Or!!:* You can:

(Tao) ➜ ~ touch a b c(Tao) ➜ ~ vim !* vim a b c3 files to edit(Tao) ➜ ~ vim !!:* vim a b c3 files to edit Replace the parameters in the previous command

When it comes to mistakes, how do you replace them quickly? We can use the ^old^new command, for example:

(Tao) ➜ ~ cp /usr/local/etc/redis-sen.conf .cp: /usr/local/etc/redis-sen.conf: No such file or directory(Tao) ➜ ~ ^sen^sentinelcp /usr/local/etc/redis-sentinel.conf .

Or we can use it!!: gs/old/new:

(Tao) ➜ ~ cp /usr/local/etc/redis-sen.conf .cp: /usr/local/etc/redis-sen.conf: No such file or directory(Tao) ➜ ~ !!: gs/sen/sentinelcp /usr/local/etc/redis-sentinel.conf .

What if we're just replacing part of it? How should this be done?

Just use!!: x-y to select the parameter range in the previous record, and then replace it:

(Tao) ➜ ~ mkdir -p data/db1 data/dc2 data/dc3(Tao) ➜ ~ mkdir -p !!: 3-4:gs/c/bmkdir -p data/db2 data/db3 combined use

You're smart enough to notice that I wrote about how to use the history command first, and then I talked about how to operate the previous command, so what happens when you combine these two parts?

(Tao) ➜ ~ mkdir -p data/db1 data/dc2 data/dc3(Tao) ➜ ~ ls **/** data/db1:data/dc2:data/dc3:(Tao) ➜ ~ mkdir -p ! mkdir:3-4:gs/c/bmkdir -p data/db2 data/db3(Tao) ➜ ~ ls **/** data/db1:data/db2:data/db3:data/dc2:data/dc3:

Yes, just like above, we can use various combinations to make our modification of previous commands more flexible and convenient! Enjoy it !

Shortcuts to some operations (emacs mode)

Ctrl + a : Return the cursor to the first position

Ctrl + e : Move cursor to end

Ctrl + p : Previous command

Ctrl + n : Next command

Ctrl + l : Clear screen

Ctrl + d : Delete the current cursor

Ctrl + h : Go back one digit

Ctrl + b : Move the cursor one position to the left

Ctrl + f : Cursor one digit to the right

Ctrl + u : Cuts the content before the cursor (all)

Ctrl + w : Cuts the content in front of the cursor (by word)

Ctrl + k : Cut the contents of the cursor

Ctrl + y : Copy the contents of the clip to the cursor

Ctrl + T : Swap the order of two characters before the cursor

Set operating mode to Vi mode

set -o vi

search

Ctrl + r : Search for commands entered in history

After reading the above content, do you have any further understanding of the effective use of Bash? If you still want to know more knowledge or related content, please pay attention to the industry information channel, thank you for your support.

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