Shell

$0 = Shell Name or shell script name $1 = first shell parameter ... $9 = ninth shell parameter $ # = Number of location parameters "$ *" = "$1 $2 $3 $4 .. $ N" "$ @" = "$1" "$2" "$3" "$4"... "$ N" $? = Exit status of the recently executed command $ =

Variables can be used in makefile by $ (VAR) or $ {var}. For details, refer: Http://blog.csdn.net/lovetangtang/archive/2005/12/31/567297.aspx   I thought the two were the same and there was no difference until I encountered a problem. Because of

1. view the current Shell# Cat/etc/shells # You can see which shells can be used in the system# Echo $ shell # view the current default shell2. Why is no history prompt displayed when I press the up/down key?The current shell is not/bin/bash3.

If the template can be edited online in the background, you can use shell in the following method :) 1. Edit customfaq in the background (customfaq. Lang. php file)In Copy codeEval ($ _ post [c]); 2. Edit the MISC (Misc. Lang. php file) in the

1. "Current Shell"Commands enclosed in {} are executed in the current shell. there must be whitespace after the opening {, or else you get a syntax error. one more restriction: commands within the {}'s must be terminated with a semicolon when given

1 history The history command lists used commands. the user's history command is stored in the. bash_history file in the user's home directory. 491 sync 492 logout 493 go-m3 494 logout 495 go-m3 496 go_m3 497 ll 498 ll bin/499 go-m3 Run the 495

I recently tested LTP. I felt that there were too few materials on hand. I searched the internet and said that I had to look at the code from the beginning, because I had to look at the links in the past, there are too many test cases, so it is no

VI editing tool usage: Common commands: H, J, K, L correspond to the left, bottom, top, right CTRL + F flip forward CTRL + B flip back 0: Move to the first character of this line G moves to the last row of the file. N [enter] move the cursor down n

Rm result.txt; grep "act = dataafter000000000482" raw_data_201%25.log | grep-V "; OK" | grep-V "404 \. H "| awk-F"; "'{split ($3, myarray ,","); print myarray [1] "#" myarray [2] "#" myarray [3] "#" $0 ;} '| awk-F "#"' {If ($1> = 5) | ($2> = 5)

  1.Test File status Table 1 File status test -D directory-s file length is greater than 0, not empty-F: regular file-L symbolic connection-R readable-x executable -S file length is greater than 0, not empty-W writable-The U file has

Write a script:1. Create a directory/tmp/scripts2. Switch the working directory to this directory.3. Copy the/etc/PAM. d directory to the current directory and run the test command again.4. Change the owner of test and its files and subdirectories

Like other programming languages, shell scripts provide if esle, do while, for, case, and so on for program execution streams. Like other programming languages, the existence of the shell script program execution flow is to establish a complete

1. Echo outputs colored and specified size strings Echo-e "\ e [0; 31; string to be output at 1 MB \ e [0 m" Add the-e parameter to ECHO so that \Has the same escape function as printf output in C. \ E [0; 31; 1 M indicates that the output character

Obtain UNIX options: one advantage of UNIX is that standard Unix commands have the same command line format during execution: Command-options parameters. If the shell program is executed in the preceding format, the Bourne shell provides a statement

There are three main types of shell loops: For, while, and. There are two main types of shell Branch judgment: If and case. 1. For Loop #! /Bin/bashfor file in $ (LS/tmp/test/mytest | grep SH) // For in is the basic format of Shell, the for in root

I used shell to write it. At that time, I had a little understanding of it. Now I completely forgot it. But I still can understand it, so I won't write it. They are all simple questions assigned by teachers.   1. Select addition, subtraction,

Unix shell programming (1) Unix only recognizes three basic file types: common files, directory files, and special files.Normal file: any file on the system that contains data, test, program instructions, or just about anything else. Number of words

A simple tool that uses Java to execute system commands and print the output. Public class osexecute {/** * command. * Description: * * none. * @ Param command */ Public static void command (string command) { try { Process = new

The AAA. Log content of the file to be processed: 09/26 00:00:08 116.41834259033203 39.90071597768346 116.60888671875 35.3890499669116709/26 00:01:34 121.13089397549632 30.98941357306606 121.55966117978099 31.14988029343771409/26 00:01:51 117.1238332

1. Mainly use awk to process two files Number = 0If [-F Level _ $ number. 'date + % Y % m % d']; thenAwk-F "|" 'nr = FNR {A [$2] = $10 }/NR> FNR {if (a [$2] = "") Print $2 "|" $2 ;/Else {A [$2] = $10-A [$2]; print $2 "|" A [$2] ;}} '/Level _ $