List of Books


General Overview

Introduction to kernel

The Buffer Cache

Shell Programming

Unix Shell Commands

Welcome to the command line

Moving around the FileSystem

Commands for moving around the file system include the following:

Manipulating Files and Folders

You can manipulate files and folders using the following commands:

Note: If you are using mv with sudo you will not be able to use the ~ shortcut. Instead, you will have to use the full pathnames to your files.

Permissions are based on a fairly simple model. You can set permissions for user, group, and world, and you can set whether each can read, write, and execute the file. For an example, if a file had permission to allow everybody to read but only the user could write, the permissions would read rwxr-r-. To add or remove a permission, you append a + or a - in front of the specific permission. For example, to add the capability for the group to edit in the previous example, you could type chmod g+x file.

System Information Commands

System information commands include the following:

The following commands list the hardware on your computer, either a specific type or with a specific method. They are most useful for debugging when a piece of hardware does not function correctly.

Searching and Editing Text Files

Search and edit text files using the following commands:

Dealing with Users and Groups

You can use the following commands to administer users and groups:

Getting Help on the Command Line

This section will provide you with some tips on getting help on the command line. The commands -help and man are the two most important tools at the command line.
Virtually all commands understand the -h (or -help) option which will produce a short usage description of the command and its options, then exit back to the command prompt. Try man -h or man -help to see this in action.
Every command and nearly every application in Linux will have a man (manual) file, so finding them is as simple as typing man command to bring up a longer manual entry for the specified command. For example, man mv will bring up the mv (Move) manual.
Some helpful tips for using the man command include:

There are also info pages, which are generally more in-depth than man pages. Try info info for the introduction to info pages.

Using Wildcards

Sometimes you need to look at or use multiple files at the same time. For instance, you might want to delete all .rar files or move all .odt files to another directory. Thankfully, there are series of wildcards you can use to acomplish this.

Executing Multiple Commands

Often you may want to execute several commands together, either one after another or by passing output from one to another.

Run Sequentially

If you need to execute multiple commands in sequence, but don't need to pass output between them, you can run them using ; between each command. Each command will be executed, and the following command will be run. If you want to make the running of the second command conditional on the successful completion of the first command, separate the commands with &&.

If you need to execute multiple commands in sequence, but don't need to pass output between them, there are two options based on whether or not you want the subsequent commands to run only if the previous commands succeed or not. If you want the commands to run one after the other regardless of whether or not preceding commands succeed, place a ; between the commands. For example, if you want to get information about your hardware, you could run lspci ; lsusb, which would output information on your PCI buses and USB devices in sequence.

However, if you need to conditionally run the commands based on whether the previous command has succeeded, insert && between commands. An example of this is building a program from source, which is traditionally done with ./configure, make, and make install. The commands make and make install require that the previous commands have completed successfully, so you would use ./configure && make && make install.

Passing Output

If you need to pass the output of one command so that it goes to the input of the next, you need something called piping after the character used between the commands, | , which looks like a vertical bar or pipe.
To use the pipe, insert the | between each command. For example, using the | in the command ls | less allows you to view the contents of the ls more easily.