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Recently around here for a long time ah, now reluctantly come out, share a little understanding of their ownExit statusA program once run must have only two kinds of results, either success or failure, the result of success is the same, the reason

Compile-language:The program needs a special compilation process before execution, which compiles the program into a machine language file, the runtime does not need to be re-translated, the results of the direct use of the compilation is OK. The

#1, print the usage of the mounted directory, the default is separated by a spacedf-ph | awk ' {print $5,$6} '#2, separated by a space, colon, \ t, semicolonAwk-f ' [: \ t;] ' ' {print '} '#3, Print lines 3rd through 5th in the 6.txt file, nr

echo $PATHvar =aecho $varexport var1=11echo $var access relationship: Whereis yum File/usr/bin/yumvi/usr/bin/python script: Create a sh.sh #!/bin /bash The following statement uses what to parse echo $varvar 1=12echo $var 1sleep 10echo "Hello" echo $

I like a wordThe only-to really learn scripting are to write scriptsThe only way to learn a script is to write a scriptBetter command-line parameter detectione_wrongargs=85 # non-numerical argument (Bad argument format).41 ## case "$" in# "") lines=5

Linux Problem Set1 Linux setting environment variables and where to save1. Display Environment Variables Home$ echo $HOME/home/terry2. Set a new environment variable welcome$ exportwelcome= "hello!"$ echo$welcomeHello!3. Use the ENV command to

Linux script (shell) programmingAh, yesterday on the Internet to see an article about Linux/unix shell, think of their last write this thing is also a year ago, think about it is almost forgotten.or tidy up, do a review, it may be used in the future,

Transferred from: http://www.1987.name/151.html　　The Read command is an internal command for reading input from a terminal or a file, and the Read command reads an entire line of input, and the newline character at the end of each line is not read

Environment Variables $HOMEHome directory of the current user $PATHA colon-delimited list of directories to search for commands $PS 1A command prompt, usually a $ character, but in bash, you can use some more complex values. For

1. Display Environment Variables Home$ echo $HOME/home/redbooks2. Set a new environment variable Hello$ export hello= "hello!"$ echo $HELLOHello!3. Use the ENV command to display all environment variables$

The shell is the interface between the user and the Linux operating system.CCat Zdd Browse the contents of a ZDD fileCat Zdd1 Zdd2 Browsing the contents of multiple filesCat-n ZDD Browse the contents of a file Zdd and display line numbersCD back to

#! /bin/bashpid=$ (pgrep Hello) echo ${pid}The script name is hello_test.shAlways returns two values when a hello process existsWhen the hello process does not exist, the return value is not empty, always returns a value, runs multiple times, and

Reference: http://blog.csdn.net/wanglang3081/article/details/49423105 (1) Makefile is essentially a shell script, that is, each command is a shell process, and the shell process exits when it finishes running. (2) Shell code line, if there is =,

Shell variables: Local variables and environment variablesBasic elements:#！ /bin/bash#VariableProcess ControlHome: The current user's home directoryPath: The current user's executable file search pathLANG: The default language the program should

File and directory operation commands, organized according to the following ideas, feel more convenient to remember and use1. Create a binary fileTouch F12. Write data to the fileecho "Hello" >> F1echo "World" >> F1 (the world is appended to

CCat Zdd Browse the contents of a ZDD fileCat Zdd1 Zdd2 Browsing the contents of multiple filesCat-n ZDD Browse the contents of a file Zdd and display line numbersCD back to the start directory, that is, just logged into the system directory, CD

function allows us to divide a complex function into several modules, which makes the program structure clearer and the code reuse more efficient. Like other programming languages, the Shell supports functions as well. The Shell function must be

PHP calls Curl Prompt error: SSL certificate problem, verify that CA cert is OK. Details:error:14090086:ssl routines:ssl3_get_server_certificate:certificate verify failed. This is due to a certificate expiration.Ssl-error You need to download the

1. Show Environment Variables Home $ echo $HOME /home/redbooks 2. Set up a new environment variable Hello $ export hello= "hello!" $ echo $HELLO Hello! 3. Display all environment variables using the ENV command $ env

Linux is a multi-user operating system. After each user logs on to the system, there will be a dedicated running environment. Typically, the default environment for each user is the same, and this default environment is actually the definition of a