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Technology Help Desk
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Basic UNIX Commands

Use the following commands to help you manage your UNIX account.
IMPORTANT: The UNIX (Ultrix) operating system is case sensitive. All commands must be typed in lower-case
letters unless noted otherwise.

Displaying a Directory
ls-- Lists the names of files in a particular UNIX directory. If youtype the ls command with no parameters or qualifiers, the command
displays the files listed in your current working directory. When you give the ls command, you can add one or more modifiers to get
additional information.
Example: ls
Result: Lists the names of files in your default directory, in alphabetical order.
Example: ls -l
Result: Gives a "long listing" of the files in your directory.In addition to the file name, the long listing shows protection information,
file owner, number of characters in file, and the date and time of the last change to the file.
Example: ls -a
Result: Causes all your files to be listed, including those files that begin with a period (i.e., hidden files).
For more information, type man ls at the UNIX system prompt.

Displaying and Concatenating(Combining) Files
more-- Enables examination of a continuous text one screenful at a time on a terminal. It normally pauses after each screenful,
printing -- More -- at the bottom of the screen. Press to display one more line. Press the to display
another screenful. Press the letter Q to stop displaying the file.
Example: more newfile
Result: Displays the contents of “newfile” one screen("page") at a time.
For more information about this command, type man more at the UNIX system prompt.
cat-- Displays the contents of a file on your terminal.
Example: cat newfile
Result: Displays the contents of the file “newfile” on your terminal.
Example: cat newfile oldfile
Result: Displays the contents of two files -- “newfile” and “oldfile” -- on your terminal as one continuous display.While a file is being displayed, you can interrupt the output by pressing and return to the UNIX system prompt.
suspends the terminal display of the file and the processing of the command. To resume display, press . The
interrupted command displays lines beginning at the point at which processing was interrupted.
The cat command is also used to concatenate (combine) files and put them intoanother file. If you concatenate files to another one
that already exists, the existing contents are permanently lost.
Example: cat fileone filetwo filethree > newfile
Result: Links together three files -- fileone, filetwo and filethree -- into a new file called “newfile”. The original files remain intact.
File: Basic UNIX Commands
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June 2000
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For more information aboutthe cat command, type man cat at the UNIX system prompt.

Copying Files
cp-- Makes copies of your files. You can use it to make copies of files in your default directory, to copy files from one directory to
another directory, or to copy files from other devices.
Example: cp fileone filetwo
Result: Copies the contents of fileone to a file named filetwo. Two separate files now exist.
Example:cp /usr/neighbor/testfile .
Result: Copies the file testfile from the directory /user/neighbor to your UNIX account. The period( . ) at the end of the command line
indicates that the file is to be copied to your current working directory and the name will remain the same.
To copy a file from another user’s directory on UNIX, you must know the person’s username.
Example: cp ~username/file1yourfile
Result: Copies the file "file1" from user to your UNIX account. The name of the file in your directory becomes yourfile. (Protections
must be set for file to be readable by you in user abcst’s directory in order to be able to copy the file.)
For more information, type man cp at the UNIX system prompt.

Deleting Files
rm-- Deletes specific files. You can enter more than one file...