Basic Linux Commands

Basic Linux Commands
This list comes courtesy of Mark Rais, our senior editor.

NOTE:
All of these commands should work from your command prompt (regardless which shell you're using). Just in case some folks were not aware, you MUST press enter to invoke the command and the EX: stands for example and is not part of the command. Commands are denoted in courier type font. And of course, if they don't work or help you, we appologize!

Command	Summary Use
Use cd to change directories	Type cd followed by the name of a directory to access that directory. Keep in mind that you are always in a directory and allowed access to any directories hierarchically above or below. Ex: cd games If the directory games is not located hierarchically below the current directory, then the complete path must be written out. Ex: cd /usr/games To move up one directory, use the shortcut command. Ex: cd ..
Use mkdir to create new directory	Use mkdir to make/create a brand new directory Type mkdir followed by the name of a directory. Ex: mkdir testdir
Use rmdir to remove an existing directory	Use rmdir to remove an existing directory (assuming you have permissions set to allow this). Type rmdir followed by a directory's name to remove it. Ex: rmdir testdir You CAN'T remove a directory that contains files with this command. A more useful command is rm -r that removes directories and files within the directories. You can read more about this in Commands for Beginning Admins The rmdir command is used mostly to remove empty directories. If you have a desire to use this command then you'll need to delete or move the files before attempting to remove a full directory.
Use ls to list files and directories	Type ls to see a list of the files and directories located in the current directory. If you’re in the directory named games and you type ls, a list will appear that contains files in the games directory and sub-directories in the games directory. Examples: ls Mail ls /usr/bin Type ls -alt to see a list of all files (including .rc files) and all directories located in the current directory. The listing will include detailed, often useful information. Examples: ls -alt ls -alt /usr/bin If the screen flies by and you miss seeing a number of files, try using the \|more at the end like: ls -alt \|more * In Bash (Linux shell) often the abbreviated command L is available. To get a verbose listing of files and directories you could therefore simply type: l
Use man to pull up information about a Linux command	Type man followed by a command to get detailed information about how to use the command. Ex: man ls Type man -k followed by a word to list all of the commands and descriptions that contain the word you specified. Ex: man -k finger
Use more to read the contents of a file	Type more followed by the name of a text file to read the file’s contents. Why do we exmphasize using this on a "text" file? Because most other types of files will look like garbage! Ex: more testfile.txt
cp	Type cp followed by the name of an existing file and the name of the new file. Ex: cp newfile newerfile To copy a file to a different directory (without changing th e file’s name), specify the directory instead of the new filename. Ex: cp newfile testdir To copy a file to a different directory and create a new file name, you need to specify a directory/a new file name. Ex: cp newfile testdir/newerfile cp newfile ../newerfile The .. represents one directory up in the hierarchy.
Use pwd to list the name of your current directory	Type pwd and hit enter. You'll see the full name of the directory you are currently in. This is your directory path and is very handy. This is especially handy when you forget which directory you’ve changed to and are trying to run other commands.
mv	Type mv followed by the current name of a file and the new name of the file. Ex: mv oldfile newfile Type mv followed by the name of a file and the new directory where you'd like to place the file. Ex: mv newfile testdir This moves the file named newfile to an existing directory named testdir. Be certain you’re specifying a directory name or the mv command alters the name of the file instead of moving it.
Use rm to remove the file	Type rm followed by the name of a file to remove the file. Ex: rm newfile Use the wildcard character to remove several files at once. Ex: rm n* This command removes all files beginning with n. Type rm -i followed by a filename if you’d like to be prompted before the file is actually removed. Ex: rm -i newfile rm -i n* By using this option, you have a chance to verify the removal of each file. The -i option is very handy when removing a number of files using the wildcard character *.

Want more? Try Basic Linux Commands. Perhaps you're ready for our Commands for Guru Wanna-bees or review the Beginner commands for Server Administration.