Bash
Bash (short for Bourne Again SHell) is the main scripting language used to provide a command line to Linux. I covered it briefly in Linux 101, but I will be covering it more in depth here. Very rarely will you write entire programs in bash, but it is a quick way to do many tasks all in one if you master it, it's just a little confusing as most lower level languages tend to be at times.
The most basic thing with bash, is that there is a variable that sets what directories to look for executable files. Every time you run a command, it searches these folders for a matching file to execute. These files can be anything, from python scripts to bash scripts to compiled executable files.
Bash builtins
The following is a list of the most common built in commands in bash with examples:
- alias
alias dir=ls- Will create a special note that says "hey, if this command is executed, run this command instead." The example will basically say if the command dir is typed, run ls instead.
- echo
echo "bash"echo "$PATH"- Prints out the text passed as an argument. Can be used in conjunction with variables to view them.
- cd
cd Desktop- Changes the working directory.
- export
export MYVAR="PASSME"- Sets variables to be passed to child processes of the shell itself.
- history
- source
- pwd
- printf
- variables
- exit
- logout