UNIX commands
Following is a list of commonly used UNIX commands used on UMD
central system computers such bulldog. Of special
interest is the umenu command, which displays a menu of frequently used
UNIX programs and utilities; the gopher command, which connects you to
UMD's on-line information system; and the man command, which displays the
UNIX on-line documentation about a specific command.
cat filename
displays the file called filename on your terminal screen (see
more for displaying a file one screen at a time).
cc -o filename filename.c
compiles the c program in filename.c and creates an executable program
(if there are no errors) in filename. Note that the .c suffix is required
for the c source filename.
cd dirname
changes the current directory path to include dirname. For example, if
you have used mkdir dirname to create a new directory, you
could then use
cd dirname to "move into" that directory. Any files
created after the cd will be stored in this directory.
diff filename1 filename2
checks the two files to see if there are any differences between them.
Very useful for comparing an old version of a program to a new version.
cp old-filename new-filename
makes a copy of old-filename in a file called new-filename. If
new-filename already exists it will be replaced.
enscript filename
sends the contents of filename to the default laser printer is for your
account.
To print to the printer in MWAH 177:
enscript -Pmwah177 filename
To to print to the general lab queue:
enscript -Plaptop filename
The enscript command has many options. For details enter:
man enscript
One nice feature for reducing the number of pages is to print 2 reduced
pages across the width of each page (known as landscape mode). The
enscript option to do this is -2r, e.g.
enscript -2r -Plaptop filename
f77 -o filename filename.f
compiles the FORTRAN 77 program in filename.f and creates an executable
program (if there are no errors) in filename. Note that the .f suffix is
required for the FORTRAN source filename.
grep pattern filename1 filename2
searches for all lines matching the pattern specified in all of the files
specified. grep
history
prints out the last n (usually 20) commands you have
entered. You
can re-execute any command listed by entering a ! followed by the number
associated with the command on the history (for example:
!10 would re-execute command #10).
lpq
displays a list of the files waiting to print on your default printer. To
see a list of files waiting to print on the laser printer in MWAH 177 enter
lpq -Pmwah177
ls
lists the names of the files in your current directory.
ls -l
lists the names of the files in your current directory giving more
information such as when the files were last modified, what protections
they have, and how many characters long each file is.
man command
displays the manual page(s) for a specific command on your screen. For
example, you can find out more about man by entering man
man, or find out man ls.
mkdir dirname
creates a directory called dirname. A directory can be thought of as a
folder containing other files and directories. Usually, directories are
used to organize the way files are stored on UNIX. For example, you
might have a source program directory, an executable file directory, and
a documentation directory (see cd).
more filename
displays the file called filename on your terminal one screen at a time.
After displaying a screen, more prompts you with a line like "--more--"
at the bottom of your screen. Press the space bar to obtain the next
screenfull, or type a "q" to quit displaying the file.
mv old-filename new-filename
renames the file old-filename to new-filename. If new-filename already
exists it will be replaced. mv can also be used to do
other things (enter man mv for details).
pico
a simple, easy-to-use, text editor. pico provides on screen
menus
and on-line help. pico is the editor used within the
rm filename
deletes the file called filename. Usually the system will ask you if you
are sure, and you must reply by entering a "y" to remove a
file. Note
that the removal of a file is permanent - do not rm a file that you might
need.
rmdir dirname
removes the directory dirname. Note that all files that exist in dirname
must be removed (see rm) before you can use
rmdir.
script
makes a copy of your terminal session in a file named "typescript".
script must be stopped by entering a "CTRL D" (hold down
the CTRL key
while typing a "d"). script writes the
terminal session (including
everything you type and everything the computer types) into the file
named "typescript". After you stop script, you can print
the file
typescript by entering: print typescript.
script must be stopped before
UNIX will allow you to log off, so if you see the message "Not login
shell", try entering a "CTRL D".
tin
tin is a program for reading and posting to Usenet newsgroups. It is also
available from umenu (see below). See IS handout U10: Using tin.
umenu
an easy-to-use menuing system that presents you with most of the commonly
used options people use the UNIX systems for, including electronic mail,
reading campus announcements and other Usenet news groups, changing your
default printer, connecting to gopher, and working with your central
system files.
vi filename
edits the file filename using the vi editor.
vi is a powerful, although
somewhat complicated editor useful for writing and editing computer
programs. A handout containing commonly used vi
commands is available in
the UMD computer labs or from the Information Services Help Desk. The
following sequence of characters will always get you out of
vi (type them
carefully, and ignore whatever you see on your terminal): ESC : w
q (the
Escape key, the : key, the w key, the
q key,) and then press
<return>. Upper/lower case matters - do not use the
capital W or Q keys.
who
prints out a list of users currently logged onto the system.
w
prints out a list of users currently logged onto the system, and includes
what they are currently doing.
| Did you find what you were looking for?
YES
NO |
©2003 Regents of the University of Minnesota. All rights reserved.
The University of Minnesota is an equal opportunity educator and employer.
Last modified on 10/06/05
| Contact ITSS |
Privacy
|