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Similar to awk Functions Example 1 $ A = 'echo root: X: 0: 0: Root:/root:/bin/bash | cut-D: -F 1,5 'shuohailhl @ shuohailhl-PC/cygdrive/d $ echo $ aroot: Root In the preceding example, the root: X: 0: 0: Root:/root:/bin/bash command is

Basename is the name left after the directory is removed.Example: shell> temp =/home/temp/1. TestShell> base = 'basename $ temp '(reverse quotation marks)Shell> echo $ BaseResult: 1. TestDirname is the DirectoryExample: shell> temp =/home/temp/1.

/*************************************** ******************************* Author: Samson* Date: 08/18/2012* Test Platform:* GNU Linux version 2.6.29.4* GNU bash, version 4.0.16 (1)-release (i386-redhat-linux-gnu) ************************************

Linux ShellTruncation character variableThe first 8 bits of the signature are as follows:1. expr substr "$ A" 1 82. Echo $ A | awk '{print substr (, 1, 8 )}'3. Echo $ A | cut-c1-84. Echo $5. expr $ :'/(.//).*'6. Echo $ A | dd BS = 1 COUNT = 8 2>/dev/

(1) Python //ArticleAs mentioned inHttp://blog.chinaunix.net/u/12325/showart_217175.htmlEither way, And popen. Output = subprocess. popen (['Ls', '-l'], stdout = subprocess. Pipe, shell = true). commun Icate () Print Output [0] Another method is

Example about Linux Shell #! /Bin/bash echo "Hello world! " echo" Hello $ LOGNAME, it's nice talking to you " echo" U present working on a machine is 'uname-N' " echo" U Present working directory is $ (PWD) " echo" Bye for now $ LOGNAME. the time

1. String Truncation (1) intercept the string before and after a specified character [Root @ gd86 applications] # Var = Hello: zkl: zyh [Root @ gd86 applications] # echo $ {var %: *} returns the first string from right to left.Hello: zkl[Root @

Difference between $ * and $ @ in Shell A little bit about $ * and $ @ is also learned by cainiao. $ *All location parameters are used as a word.Note: "$ *" must be referenced.$ @It is synonymous with $ *, but each parameter is an independent ""

Unix shell programming (4)   Cut commandYou can extract the required data fields from the data file or command output.Command Format: Cut-cchars FileChars indicates the characters to intercept, which can be numbers.File indicates a file. If file is

This article summarizes some of my frequently used shell commands or some short commands. 1. view the compile time of a tool; ll $(which appname) 2. Common for Loops for i in 1 2 3 4 5; do echo "$i"; done； for((i=140;i 3. Commonly Used File

Common grep command syntax 1. Double quotation marks and single quotation marksWhen you input a string parameter in the g r e p command, it is best to enclose it with double quotation marks. For example, "m y s t r I n g ". There are two reasons for

When I went to bed in chemistry today (Khan ......) dreaming, dreaming of penetrating a magic = off PHP injection point, and then happy mouth water flow (..... sleep too much), suddenly woke up, and immediately wrote the dream idea on the paper:

Mycommand> mylog.txt 2> & 1 should be the most classic usage. Command results can be output in the form of "%>", % indicates the file descriptor: 1 indicates the standard output stdout, and 2 indicates the standard error stderr. The default value of

1. Using securitycrt in the options-> session Options dialog box, there are many options for emulation under terminal. the Linux server has different terminal simulation packages called the terminfo database, each type corresponds to a terminfo File

Control script, Stat. Sh PID_NUM=$$PID_FILE=stat.pid#echo "pid : "$PID_NUMPROG_NAME=$0ACTION=$1usage() { echo "Usage: ${PROG_NAME} {start|stop|restart}" exit 1;}start(){ sh ./stat_run.sh & PID_NUM=$! echo "worker pid is " $PID_NUM

/*************************************** ******************************* Author: Samson* Date: 08/17/2012* Test Platform:* GNU Linux version 2.6.29.4* GNU bash, version 4.0.16 (1)-release (i386-redhat-linux-gnu) **************************************

Linux scripts are huge and powerful. Definition: Function Name () // function can be omitted { Command } Call: directly use the function name in the script. Of course, you can also include parameters such Function Name parameters (separated by

In Shell, only one process can be implemented at a time:   1. lockf command   2. Simple implementation: I = 'ps-Ef | grep [N] ew_mvbackup | WC-l' if [$ I-GT 1];ThenEcho "wait for the other mvbackup finish! "Exit-1Else # Do something here   3.

The most important script language in Linux is Bash. I will write this (I will only use this :)). Compared with other development languages (such as C), bash is a relatively simple language, mainly used to write some script code, some batch

1. Write a script to calculate the factorial of 10 in a loop. #! /Bin/sh factorial = 1 for a in 'seq 1 10' DO factorial = 'expr $ factorial/* $ a' done echo "10! = $ Factorial "   2. Write a script. After the script is executed, print a