Linux Command Line or Shell Resources

Posted by JD 09/12/2017 at 20:00

There are times when not using a GUI is a smart option.

Not everyone has the desire to read a book and slowly learn Unix/Linux in the formal methods that have been proven. After all, we all learn best by scratching a personal itch. Learning bash, sh, ksh, tcsh, zsh, fish, or any of the multiple other Unix shells isn’t any different. All of them are base on the Bourne Shell, sh, so they are usually similar. Almost all Unix systems today default to bash, the Bourne-again shell .

First, the shell, the command line, the terminal are each different things, but people new to Unix-like systems get them confused. So, let’s clarify a little. The Terminal is the program in which the shell runs. The shell provides a command line interface. Different shells will behave differently. There are different terminal programs too.

Too someone new, the normal terminal program running on most Unix-like systems by default is gnome-terminal or a variant of it. There are also slightly stripped down terminals like lxterm, lxterminal and more stripped down versions like uxterm and xterm. There are probably 30 other terminal programs, each with the same basic options, but how those options are set usually differ. I prefer the uxterm – it is light, fast, supports utf-8, Settings are controlled using the normal X/Windows methods, which most Linux users have never learned to use.

There are probably 20 different shell programs too. Every user can change which shell they use by default from a list configured by the system admin. bash is usually the default and it is really an amazing shell. It is trivial to try out a different shell – just run the program from any terminal and use it.
On one of my systems, these are the allowed shells.

$ more /etc/shells 

\# /etc/shells: valid login shells

/bin/sh

/bin/dash

/bin/bash

/bin/rbash

If I installed tcsh or zsh, I would expect that file to be modified in include those shells.

Anyway, onto some links:

There are probably thousands of other sites covering all the basic commands. Don’t forget to google for “linux cheat sheets” too and to RTFM. All the commands on your linux system have manpages. Some are excellent.