UNIX Commands
Note: UNIX is case sensitive. Be sure to type the commands as they are listed. UNIX considers the capital and lower case versions of the same letter to be totally different. Be careful.
cd Changes the current working directory to the directory you indicate.
To move back to your home directory, type cd.
To move to a directory that is not a subdirectory off the current working directory, you can use a full pathname – one that begins with a slash. For example, to look around in the /usr directory (where all home directory are stored), you can type
cd /usr
Example:
You log in and do some work in your home directory. Next, you want to move into your budget directory to see which file are there you type:
cd budget
clear Clears the screen. This command doesn’t’ affect files or jobs – it just clears the clutter from your screen.
clear
Example:
You just tried to use the cat command to lock a word-processing document and your screen is full of gibberish. Type clear.
cp Copies one or more files.
If you know DOS, you may think that omitting the second filename tells cp to copy a file into the current working directory. This technique doesn’t work in UNIX – instead, use a period (.) to copy a file into the current directory.
NOTE! What happens if you copy a file to a new name and a file already has that name? Assuming that you have permission to write (change) the existing file, UNIX blow it away and replaces it with the copied file. Always use the ls command to check that your filename isn’t already in use. And use the –I to tell cp to ask before overwriting a file.
cp [-I] oldfiles newfiles
or
cp [-I] [-r] oldfiles directory [/newfiles]
-I Ask before you replace an existing file with a copied file
ksh fix.it.up
mkdir Creates a new directory.
mkdir directory
directory – Specifies the name of the new directory. If the name doesn’t begin with a slash, the new directory is created as a subdirectory of the current working directory. If the name begins with a slash, the name defines the path from the root directory to a new directory.
You must have permission to write in a directory to create a subdirectory to it. For the most part, you should create directories in your own home directories or subdirectories of it.
mkdir temp
more Display information one screen at a time so that you can read it easily.
ls |more
You receive a file (new.fil). To display it on your screen type.
more new.fil
mv renames a file or moves it from directory to another.
mv [-I] oldname newname
ps Display information about your processes (jobs).
You wonder weather the process you ran in the background is still running. Type:
ps
to see a list of all your processes. To see more information about them type
ps –l
pwd Display the name of the current working directory.
rm Deletes (removes) a file permanently.
