bash history

************************************************************************* * * * Original:blog.csdn.net/clark_xu Xu Changliang's Column************************************************************************? time to read the file#!/bin/bashFor file in ' Ls/root 'DoStat $file >1.txtSed-n "7p" 1.txt>2.txtUsetime= awk-f ":" ' {print $2.txt} 'echo "Time=" $file $usetimeDone? reads each line of the file while statement. Cat Afile | While Read onelineDoEcho $onelineDone? reads each line of the file

") confuse bash. After bash expands "$ myvar", the Code is as follows: [ foo bar oni = "foo bar oni" ] Bash considers that there are too many independent variables in square brackets because the environment variables are not placed in double quotes. Double quotation marks can be used to enclose string independent variables to eliminate this probl

command, are immediately invalidated. Each user has a private bash file in the user's home directory, with a file name of. BASHRC, modified to restart the Bash program or the source command or "." will take effect,Second, bash's shortcut keys:C: Represents the CTRL keyM: Represents the ALT keyE: Represents the ESC keyDEL: Represents the BACKSPACE keyCommon:C-l: Clear ScreenC-A: Jumps the cursor to the begi

More than 2000 years ago, a scholar suffered a great humiliation, but "do not fall Lingyun's ambition", with blood for ink, the mind for paper, completed a "historian of the Swan song, no rhyme Li Sao" history masterpiece. This is Sima Qian and his "historical records".A common historian and a masterpiece, what is it that integrates them into one? Who initiated the "Shiji" of the eternal grand? Who changed the life of Sima Qian?"Historical records" re

software. Advantages of shell: the shell on the command line interface is also remotely managed: the command line interface is a shell (/etc/shells file) that can be used in Linux to manage the legitimate shell and/etc/shells functions of key systems of the system quickly ): /bin/bash (Bourne Again SHell, the default shell in Linux)/bin/ksh (Kornshell developed by ATT Bell lab and compatible with bash)/bin

Bash Preface This article is translated from the bash chapter in slackware Linux unleashed (Third edition), but some necessary deletions are made, and some changes are made according to the actual situation, if necessary, refer to the original article. If you have any questions about this article, please contact me: con@nease.net Introduction This article will introduce in detail the most common shell and

the mathematical expression is stored as a string and is not evaluated.Two, references and metacharactersIf everything is a trivial string with no special features, it cannot form a programming language. In bash, there are a number of symbols with special meanings, such as the "$" symbol being used for string expansion, and the "" symbol for the command to execute in the background, "|" Use as a pipe, > What is the difference between a quoted string

completion is followed by the alias, reserved word, shell function, shell internal command, and finally the executable file name. [ CTRL - X , ! ] The text before the mark Point as the command name and the completion of the article can be complete. ALT-TAB Compare the text in front of the mark point to the text in the history to find a match and try to complete the completion. ALT-{ Complete the file name, and pu

The command history of Bash's underlying features:Command history: The shell process saves commands that were previously executed by the user in its session~] #historyCustomizing the history function, which can be implemented by environment variablesHistsize:shell the number of commands history that the process can ret

SOURCE : Tpircsboy's blog (@churechill123) Many people who have used Linux for a period of time have already been able to play the basics of Linux in some basic ways, but without systematic learning it is easy to lack some practical skills. This series of articles describes some of the techniques that can improve the effectiveness of bash, mainly about historical command operations and some shortcut keys, so that you double your productivity at the co

The basic features of bash are as follows:First, the alias of the command--alias commandThe alias used to define and display the command, UNALIAS to revoke the defined alias, but note the following:The effect of 1.alias is limited to the lifetime of the current shell;2. If you modify the. BASHRC configuration file, the saved alias will not take effect immediately and will only take effect after reloading the contents of the file.3. In order to ensure

Tags: linux command bash linux command line file name PAC space append different row15 Examples of mastering the Linux command line historyWhen you use Linux command lines frequently, using history effectively can increase productivity. In fact, once you have the following 15 examples, you will find it more interesting and interesting to use a command line.1. Use Histtimeformat to display timestampsTypicall

better do it myself.It's really hard to get a friend. I'm glad to know them in this homecoming. The road ahead is very long, and the line and cherish. I think. The story of me and them just started.Not to be continued.Good luck!RobinJuly 20, 2014 related articles Program Ape's Struggle History (37)--University dynastic history (I.)--Opening Program Ape Struggle

first column of each row indicates the type of the file[[Email protected]]# ll/usrtotal124dr-xr-xr-x. 2 root root 36864 10:15 bin-: Normal fileD: Catalog fileB: Block device filesC: Character device fileL: Symbolic Link file (similar shortcut)P: Named pipe fileS: Socket fileBasic features of Bash (i)( 1 ) Command HistoryA list of commands that bash has executed in the pastThe command

popsicles, selling various snacks, and rushing steps, there is also a leisurely manner. Various life forms a wonderful world. Guangzhou is a suitable place for people to live in. Its beautiful environment, fresh air, non-exclusive, historical, and low cost of living. There is no doubt that the air is fresh, at least N times better than Chengdu. The Morning and evening of Guangzhou are very cool, and the sea breeze is quite pleasant. There are many reasons why Guangzhou is not exclusive and its

Thinkphp browsing history implementation method, thinkphp history This article describes how to implement the thinkphp browsing history function and shares it with you for your reference. The implementation method is analyzed as follows: The history browsing function uses the cookie function to record user information

replacement symbol of the command line history. But there is no such problem in shell scripts. Unfortunately, you cannot use escape characters to escape! : $ echo "hi\!"hi\! Solution: use single quotes, that is $ echo ‘Hello, world!‘ If you must use double quotation marks, you can use set + H to cancel the replacement of command line history. set +Hecho "Hello, world!"23. For ARG in $ * $ * Indicates

HTML5 adds a new management of history, and updates the history object to make it easier to manage historical states. In modern Web applications, you can use the forward and backward buttons to switch historical pages. This allows some new pages that are not opened in the new page to move forward and backward freely, improving the user experience. Through the haschange event, you can know when the URL param

environment variables take effect:1. directly input relevant variables in the current shell. For example, if we do not want to retain the command history, we set HISTSIZE to 0.[Root @ localhost ~] # HISTSIZE = 0[Root @ localhost ~] # History Tested. However, the limitation of this setting is that it only applies to the current shell and its sub-shell. If you switch the user or log out and then log on to it

particularly useful for commands that use a long path file name as a parameter. 　　 Table 10-2 is a summary of the command line editing operation. 　　　 Command History 　　 In Bash, the history Command can save the recently executed command. The history number of these commands starts from 1, and only a limited number of