This is a summary of the few most useful commands in Unix. It is not a complete reference.
To see full details on each command, read the corresponding online
Arguments are displayed like this,
This is to remind you that
you must not type the argument text literally as it appears here, but replace it with something sensible.
For example, pathname should always be replaced with the
pathname of a file or directory.
optional arguments have square brackets around them, [like this],
and an argument of the form filename... denotes a list of one or more arguments
of the same type.
Most commands have optional flags, which are detailed fully in the
manual page. For example, ls has an optional flag -F ("indicate
file type") to make it display a special character after each file it lists indicating
whether the file is a directory, an executable file, etc. This could be used like
ls -F mydir
Always remember that in Unix, case is significant, so LS is not a
Unix command, while ls is.
- cd [pathname]
- If pathname names a valid directory, then cd
("Change Directory") makes it the new current directory for your shell.
Without an argument, cd changes to your home directory.
- ls [pathname...]
- If pathname names a valid directory, then ls displays a listing of it.
Without an argument, ls displays the current directory.
- man [section-number] topic
- The man command lets you read the online Unix manual page corresponding
to the given topic. Usually topic is just a command name. For
presents the manual page about the man command itself. The section-number
is not usually necessary, but it can be used to distinguish pages with the same name
in different sections. For example, section 1 is for user commands, while section
5 describes Unix file formats. If you're running X Windows, you may prefer
- mv filename [filename...] directory
mv filename new-filename
- The mv command has two forms. In the first form, all the named files are moved to the
named directory, retaining the same filenames.
In the second form, the file filename is renamed to new-filename. Note that if
new-filename already exists and is a directory, mv will simply move the file into
the directory instead, since this is indistinguishable from the first form of mv.
In both cases, any files in the target directory with the same name can be overwritten, although
mv will ask first, unless you disable this feature in your
- pwd displays the name of the shell's
- rm filename [filename...]
- The rm command removes all of the named files. There is no way to recover
a file deleted in this way. rm will ask for confirmation before deleting each file,
unless you have changed your startup files
to indicate otherwise.
Use rm -r (with caution!) to recursively delete a directory and all
of its subdirectories. It is safer to use
rmdir to remove a directory.
- rmdir directory-name
- The rmdir command removes the named directory, so long as
it is empty and the user has
permission to do so.
- This X Windows command starts a small window from which you can search the online
Unix manual. It is the same manual as presented by the man
command, but the user interface is nicer. You may already have xman running when you
log in. If not, read Customizing X Windows .
who is still writing this, would like to
hear your comments and suggestions.