Linux-Basics-Complete-Course-With-Notes-Slides

Using command line to get help

In this section we will learn how to use help command to get help in command line

• If you are new to using linux or bash shell or if you are not sure which command does what, there are few commands in bash that can help get started.
• Lets take a look of those

First command is whatis , this command will displays a one line description of a command does.

Syntax: whatis <command>

$ whatis date

Most of the commands internal or external come bundled with man pages which provides information about the command in detail (with examples, usecases and with command options)

Syntax: man <command>

$ man date

Several commands will provide -h or --help to provide users with the options and usecases available in a command

$ date -h
$ date --help

To search through the man page names and descriptions for instances of the keyword use apropos. This is useful if you want to look for all commands within the system that contains the specifc keyword.

Syntax: apropos <keyword>

$ apropos modpr