unix shell scripting examples

Scripting programming languages and compiled languages: Scripting programming Language: (Bash) The scripting language is usually interpreted (interpreted), which is read into the program code primarily by the interpreter (interpreter) and is translated into an internal form for execution. Advantages: can easily handle objects such as files and directories. D

list ..." {# rsync startedSet Timeout-1}-re "Bind:address already in use" {# for local or remote port forwardingSet Timeout-1}-re "is a directory| No such file or directory "{Exit}-re "Connection refused" {Exit} Timeout {Exit} EOF {Exit}}Note usage:Eg. Remote-exec "SSH [email protected] ls; echo Done "passwordOr:remote-exec "Scp/local-file [email protected]:/remote-file" passwordOr:remote-exec "SCP [email protected]:/remote-file local-file" passwordOr:remote-exec "rsync--rsh=ssh/local-file [ema

functionality is written in C or C + +, it can take two days, and generally, the script executes fast enough to allow people to ignore its performance problems. Examples of scripting languages are awk, Perl, Python, Ruby, and Shell. When to use the shell Because the shell

files under/var/logPut all the commands in one file and build up the script, here is the simplest command to stack up the script, empty the log script.Cd /var/logCat /dev/null > messagesEcho “Logs cleaned up.”Expand: Three ways to empty logs and file contents[[emailprotected] ~]# echo >test.log [[emailprotected] ~]# >test.log [[emailprotected] ~]# cat /dev/null >test.logScenario: Preserve files and empty content.Two Shell language and category Introd

In Linux or Unix-like systems, each user and process is running in a specific environment. This environment contains variables, settings, aliases, functions, and more. Here is a brief introduction to some of the common commands in the shell environment, including examples of how each command is used, and setting your own environment at the command line to improve

What is a shell script Shell scripting (English: Shell script), also known as shell Command Draft, programmatic script, is a computer program and text file, the contents of a series of shell commands, through the

What is a shell script sample Let's look at an example: #!/bin/sh cd ~ mkdir shell_tut cd shell_tut for ((i=0; i Example explanation Line 1th: Specify the script interpreter, here is the interpreter with/bin/sh Line 2nd: Switch to the current user's home directory Line 3rd: Create a directory Shell_tut Line 4th: Switch to the Shell_tut directory Line 5th: Cycle conditions, 10 cycles

Shell Script Introduction Shell is a scripting language You can use logical judgments, loops, and other syntax Functions can be custom-defined The shell is a collection of system commands Shell scripts enable automated operations, which can greatly i

curly braces to tell the shell that we're printing num variables: num=2 echo "This is the ${num}nd" This will print: This is the 2nd There are many variables that are automatically set by the system, which are discussed later when these variables are used. If you need to work with mathematical expressions, you need to use programs such as expr (see below). In addition to the usual shell variables that are

Learn Shell to now, always thought that they will not commit a very two problems, the result of this book last time made a very 2, integrity not protect AH!!! I'm under the test file path except wildcard * and? What can be used outside the same thing, the result of the $home under the implementation of RM. All right, the egg hurts for the whole afternoon! Return the wood to any one of the configuration files. Warn posterity, do not use RM Test wildcar

value. You can use curly braces to tell the shell that we're printing num variables:num=2echo "This is the ${num}nd"This will print: This is the 2ndThere are many variables that are automatically set by the system, which are discussed later when these variables are used.If you need to work with mathematical expressions, you need to use programs such as expr (see below).In addition to the usual shell variab

, The interpreter (interpreter) needs to read the source code that we wrote and convert it to the target (object), which is then run by the computer. Because each execution of the program is more than the compilation process, so efficiency has decreased.The advantage of using scripting languages is that they are mostly run at a higher level than the compiled language and can easily handle objects such as files and directories, and the disadvantage is

1. Linux Scripting Basics1.1 Basic Introduction to grammar1.1.1 StartThe program must start with the following line (must be placed on the first line of the file):#!/bin/shThe symbolic #! is used to tell the system that the parameters behind it are the programs used to execute the file. In this example we use/BIN/SH to execute the program.When you edit a good script, you must also make it executable if you want to execute the script.To make the script

Tags: ges vim editor nginx root user Form bash script expec Ash rsyncObjectiveLearn about the knowledge reserves required for Shell script programming:Vi/vim Editor Command VIMRC set to be proficientBasic commands, more than 100 skilledBasic and common Network Service commands to be: NFS, rsync, INotify, Lanmp, Sersync, SSH keyI. Shell scripting concepts and

folders, and ended up with a single command line: xcopy /e C:\Windows\assembly\GAC_MSIL G:\GAC_MSIL Then look for the desired assembly in the copied directory. Ha, now we can look at the PS code, it will be a very enjoyable thing.In addition, I found an additional assembly "System.Management.Automation.dll" through the _sfx_manifest_ file and the Reflector Analysis assembly reference, and its EXE note is "Microsoft Command-Line Shell

Often, when people refer to the "Shell scripting language", they are bash,ksh,sh or other similar Linux/unix scripting languages emerging in their minds. Scripting languages are another way to communicate with a computer. Users can move the mouse and click on a variety of ob

line string. Such as:System ("env lc_all=es_es sort infile > outfile") #以Spanish的locale排序文件.The system () function is described later. Patterns and Operations form the core of the awk program. The mode is true to operate. A normal pattern is a regular expression that is taken to match an entire input record, such as:NF = 0 #选定空记录NF > 3 #选定拥有三个字段以上的记录NR $ ~/jones/#选定字段1中有jones的记录/[xx][mm][ll]/#忽略大小写选定含xml的记录 Awk can also use a range expression, two expressions separated by commas, on the match

Shell: get started with Linux, OS X, and Unix Shell Environments In Linux or Unix-like systems, each user and process runs in a specific environment. This environment contains variables, settings, aliases, functions, and more. The following is a brief introduction to some common commands in the

] ~]# Expr 2 * 3expr:syntax errorSecond, let command[[email protected] ~]# let A=2+3[[email protected] ~]# echo $a 5[[email protected] ~]# let A=2-3[[email protected] ~]# Echo $a -1[[email protected] ~]# let A=2*3[[email protected] ~]# echo $a 6[[email protected] ~]# let A=2/3[[email protected] ~]# echo $a 0[[email protected] ~]# b=4[[email protected] ~]# c=2[[email protected] ~]# let a= $b/$c [[email protected] ~]# Echo $a 2When using let, it is generally necessary to assign them to a variable

Use PHP as the Shell scripting language, read the use of PHP as the Shell scripting language, -- English original: DarrellBrogdon, published in http://www.phpbuilder.com/columns/darrell20000319.php3) many may have thought about using PHP to write some program such as timed sending, but it is impossible to execute Darre