Contents

   

1.	man
2.	ls
3.	cd, mkdir
4.	rm, rmdir
5.	cp

      

1. "man"

Display Manual Pages

The man command will display the manual pages for most UNIX commands. For more information on any of the Unix commands below, use this to see if there is an online manual page available. For example, if you require help on the move (mv) command, you would type:

man mv

The command syntax for man is:

man commandname

By default, the man command uses another command called more to display the manual page one screenfull at a time. To display the next screen, press the space bar. To end the display before the end of the file, press the "q" key. 

2. "ls"

List the contents of a directory

Use this command to list the contents of the current directory. This will display all files and directories within the current directory in a columnar format.

You may change the format in which ls displays your directory listing by adding options to the ls command. To add an option to the command, follow the ls command with a minus sign '-' and the option(s) you wish to add. For example, ls -l will list the current directory in long format, showing size, date, and permissions. ll is a common alias or shortcut for the list long command (ls -l).

In Unix, there are files which are normally hidden called "dotfiles". These dotfiles are files that start with a dot (i.e. a period - ".") and are used by programs and shells to retain control information such as preference settings and bookmarks. To see hidden files, use ls -a to list all files, including those files whose names begin with a period. Be careful not to remove dotfiles if you're not sure of their purpose.

The command syntax for ls is :

ls [ -aAcCdfFgilLqrstux ] filename 

If you use the ls command on a directory with many files, the display will probably scroll off the screen. To avoid this, you can "pipe" the display through the more command, just as with man pages. The Unix "pipe" symbol is a vertical bar (often a broken vertical bar on your keyboard). It means "take the command on the left, and use it as input to the command on the right". For example:

ls -la | more 

Which lists the content of the current directory, in long format (-l) and includes all files (-a), and sends the listing to the more command which displays the listing one screen at a time.

3. "cd" - and     "mkdir"

Change Directory Make Directory

The "change directory" command is used to switch from one directory to another. The purpose of having multiple directories is to enable you to easily organize your files. Your directory structure should resemble a filing cabinet, with folders (directories) for each set of files.

Using cd without a directory name following it will always return you to your home directory, no matter where you are in the Unix directories. To change to a subdirectory, for example one called "skiing", you would type:

cd skiing 

To "back up" a level in the directory structure from a subdirectory to its parent directory, you can use:

cd .. 

.. is a special directory which always links a directory backwards to its parent directory, you can see this directory with the ls -a command. There is a second special directory called . which always refers to the current directory.

The command syntax for cd is :

cd [directoryname] 

For more complete information on the cd command, try man cd.

The "make directory" command is used to create a new directory. As noted above, a directory serves to organize files in a manner to similar to a filing cabinet. However, unlike most filing cabinets, a single directory may contain several subdirectories. For example, to create a directory called "Banff":

mkdir Banff 

The command syntax for mkdir is:

mkdir directoryname   

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4. "rm" and     "rmdir"

Remove files Remove Directories

The "remove" command is used to permanently delete your files from your directories. To remove a file named "whistler.ps" from the current directory:

rm whistler.ps 

To remove multiple files, use the remove command followed by the names of the files, separated by spaces. For example:

rm file1 file2 file3 

The command syntax for rm is:

rm [-fir] filename 

The "remove directory" command is used to delete your directories. The directory you wish to remove must be empty before using the rmdir command. To remove a directory called "bigsky", you would type:

rmdir bigsky 

The command syntax for rmdir is:

rmdir directoryname 

To remove a directory that is not empty (and all of its contents) you can use the rm command with the -r (recursive) option. This will recursively remove all files from a directory (or subdirectories) and then remove the directory itself. Repeating the previous example:

rm -r bigsky 

5."cp"

Copy files

The "copy" command is used to make a copy of a file in the same or a different directory. If copying to the same directory the filename of the copy must be different. This is useful for making backups or working copies of files while leaving the originals alone. To copy the file tahoe.txt to a backup file tahoe.txt.bak in the same directory:

cp tahoe.txt tahoe.txt.bak 

To copy the file named "tahoe.txt" from your home directory to a directory named "goodskiing" (without changing the name):

cp tahoe.txt goodskiing 

If you wished to rename the copied file:

cp tahoe.txt goodskiing/newname.txt 

The command syntax for cp is:

cp [ -ip ] filename1 filename2