Shell

1. Description Top selection parameters 2. Option ①-B runs in batch mode, but cannot accept command line input; ②-C: displays the command line, not just the command name; ③-D N indicates the interval between two refreshes. For example,-D 5

Shell commandsXargs Build and execute command lines from standard input Xargs can be readStdinAnd use a space character or line break character as the resolutionStdinData is separatedArguments. 1) Description Xargs [-0epn] command Options

1. Diff 1) Name Diff-find differences between two files Synopsis Diff [Options] From-file to-file Description In the simplest case, diff compares the contents of the two files from-file and to-file. 2) Option A single letter preceded

1,Which Which-shows the full path of (Shell) commands. Which [Option] 2,Whereis Whereis-locate the binary, source, and manual page files for a command Whereis [Option] filename 3,Find Find-search for files in a directory hierarchy Find [

Parentheses The parentheses structure can force the command to run in the sub-shell. Its basic format is: ( Command 1 Command 2 ... Command n ) The N commands in parentheses are run in the sub-shell. After bash version 3, the internal

1. Description /Sbin/ldconfig-configure dynamic linker Run-Time Bindings Ldconfig Option 2. Option 1)-P: indicates that ldconfig prints the names of all the shared libraries saved in the current cache file. 2)-V: ldconfig displays the

1. Description Strace-trace system CILS and Signals 2. Option 1) strace-p pid tracks a background process 2) strace-O filename outputs the trace result to the file 3) strace-T records the time spent on each system call. You can see which

Bitwise operator. Bitwise operators are rarely used in shell scripts..Their main purpose seems to be to operate and test from sockets Read variables. "Bit flipping" is closely related to the compilation language , for example, C/C ++ , in

1. Tail-output the last part of Files Tail [Option] [+/-num]... [file]... 2. Option ①-F,: Output appended data as the file grows; ②-S,: With-F, sleep for S seconds (default 1.0) between iterations. ③-N,: output the last n lines, instead of

1. About the prompt, special Variables 1) Bash has two levels of prompt. The first-level prompt is often seen when Bash is waiting for command input. The default value is the $ symbol, and PS1 is the variable value. The second-level prompt is

Http://rimuhosting.com/howto/profile.jsp   Linux Shell environment setup using/etc/profile. d /*   When a user logs in, environment variables are set from various places. That between des: /Etc/profile (for all users ). Then all the

> VI copy and paste Move the cursor to the beginning of the part to be copied. Run ESC to exit the insert mode. Press V to enter visual mode. Use hjkl to select the part to be copied. Press Y or YY to copy Move the cursor to the target

1. find Find pathname-options [-print-Exec-OK] let's take a look at the parameters of this command: path of the Directory searched by the pathname find command. For example, use "." To represent the current directory, and use "/" to represent

1. Expression writing: [2] Regex_ip = "(2 [0-4] [0-9] | 25 [0-5] | 1 [0-9] [0-9] | [1-9]? [0-9]) (\. (2 [0-4] [0-9] | 25 [0-5] | 1 [0-9] [0-9] | [1-9]? [0-9]) {3 }" It means (0-255) (point 0-255) 3 times Echo "123.1.1.1" | grep-e "$ regex_ip"

I have learned shell scripts before, but it has never been used in my work. To prevent repeated startup of PHP scripts, I need to write a shell, What I learned was finally used. I wrote this script with the knowledge points I remembered. I want to

First article written since last timeArticleTwo months have passed. This article describes how to obtain the decrypted il bytes.Code.Let's review the previous article. In the previous article, we mentioned that "After infacemaxtocode. startup is

Linux file descriptor: Three file descriptors are opened by default: standard input 0, standard output 1, error output 2 Output redirection Command-line1 [1-N]> file or file operator or device First, check whether the file on the right exists.

This series will focus on the advanced usage skills in Linux Shell. It is mainly intended for experienced Shell developers, Linux system administrators, and Linux enthusiasts. The examples in the blog mainly come from the Internet and some classic

7. grep family:1. grep exit status:0: indicates successful;1: The matching pattern cannot be found in the provided file;2: The file provided in the parameter does not exist.See the following example:/> Grep 'root'/etc/passwdRoot: x: 0: 0:

CPU resources are consumed in an endless loop. If the server has multiple CPUs, you can select the number of CPU resources to be consumed: #! /bin/sh # filename killcpu.shif [ $# != 1 ] ; then echo "USAGE: $0 " exit 1;fifor i in `seq $1`do echo