Shell Scripting Learning

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Shell script: Data batch processing, Task batch processing

The shell script file is suffixed with. SH, which is practically meaningless.

Shell Operating principle:

1. Command Relay (Create sub-process, parse execution, return result)

2. Create a process to complete a task

3. Parent process is not affected by child process errors

File/bin/bash, as a binary file, Shell interpreter (not shell script)

The relationship between bash and Shell: Lady Wang and Matchmaker

The first line in the script must be: Tell the interpreter and version, #! Called Shebang

#！ Bin/bash

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Bash test.sh

Test.sh is passed as a parameter to the executable file, the child bash,

The running process is as follows:

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Operating methods are:

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Cd,export Such commands do not create child processes, the current environment runs directly, such commands are called built-in commands. That is, through bash: the binary inside function call.

This article is from the "Small Stop" blog, please be sure to keep this source http://10541556.blog.51cto.com/10531556/1787929

Shell Scripting Learning