Shell Scripts to learn and automate task
- A Shell script is a list of commands in a computer program that is runed by the Unix Shell wich is a command line interpreter. A Shell script usually has comments that descibe the steps. The different operations performed by shell scripts are program execution, file manipulation and text printing.
- The shell is a program that takes commands from the keyboard and gives them to the operating system to perform. In the old days, it was the only user interface available on a Unix-like system such as Linux. Nowadays, we have graphical user interfaces (GUIs) in addition to command line interfaces (CLIs) such as the shell.
- Types of shell ?
cat/etc/shells
#!/bin/bash
- This #! is called shebang or hashbang. The shebang plays an important role in shell scripting, specially while dealing with different types of shell.
- The shebang is the combination of the # (pound key) and ! (exclamation mark). This character combination has a special meaning when it's used in the very first line of the script. It is used to specify the interpreter with wich the given script will be runed by default.
- So, if the first line of a script is:
#!/bin/bash. It means the interpreter should be bash shell.