Basic Commands

Basic commands for the Unix family, including Linux and Mac OS X.


Command-Chaining Operators

Syntax Description
AND - OR && - || Combining and AND and OR operator acts like an if-else statement
AND && Execute proceeding command only if the preceding command succeeds with an exit status of 0
Ampersand & Run the preceding command in the background
Group {} Group two or more commands, dependent on the preceding operand.
NOT ! Execute all except the condition provided
OR || Execute proceeding command only if the preceding command fails with an exit status of 1
PIPE | Output from the preceding command is fed to the proceeding command
Precedence () Execute commands with precedence such as in math
Semi-colon ; Run the preceding command sequentially

File Management

cd

Change working directory.

Syntax Description
$ cd ~/ Change to home directory.
$ cd .. Change working directory to one level back.

clear

Clear the terminal output.

Syntax Description
$ clear Clear the terminal output.

find

Recursively finds files within path.

Syntax Description
$ find ~/ -name basic-commands.md Finds the file basic-commands.md within the users home directory.

locate

Find filenames quickly by using a database.

Syntax Description
$ locate *.md -n 20 List filenames ending with .md, and limit queries to 20.

ls

List files within working directory.

Syntax Description
$ ls -1 *.md List files that ends with .md, and force output to be one entry per line.

man

Displays manual for the utility. Pressing q quits the process.

Syntax Description
$ man cd Displays manual for the ls utility.

mkdir

Create directory if they do not already exist.

Syntax Description
$ mkdir wiki Create directory named wiki.

mv

Move and or rename file/folder from source to destination.

Syntax Description
$ mv basic-commands.md unix/basic-commands.md Move basic-commands.md to the unix directory, and name the file commands.md.

pwd

Return working directory name.

Syntax Description
$ pwn Return working directory name.

rm

Removes directory entries. Be very careful with this command.

Syntax Description
$ rm basic-commands.md Remove file named basic-commands.md.
$ rm -rf .DS_Store Removes all Mac Desktop Servies Store files, recursively.

rmdir

Removes directories.

Syntax Description
$ rmdir docs Remove directory named docs.

touch

Create a file with default permissions.

Syntax Description
$ touch basic-commands.md Create file basic-commands.md, if it does not exist. If it does, change modification and access times.

whereis

Locates source/binary and manuals sections for specified files in a list of standard Linux places.

Syntax Description
$ whereis mame Where is the installed mame binary.

Removing .DS_Store Files

Find and remove all matches, recursively. This is incredibly useful for removing Desktop Services Store files (Mac OSX). Be sure to change into your target directory first!

$ cd wiki
$ find . -name '.DS_Store' -type f -delete

Power Management

halt

Stop the system.

Syntax Description
$ sudo halt Stop the system.

reboot

Restart the system.

Syntax Description
$ sudo reboot Restart the system.