Command
|
Description (short)
|
Example
|
Explanation
|
|
Date
|
Writes the current date to the screen
|
date
|
Mon
Nov 20 18:25:37 EST 2000
|
|
sort
infile
|
Sorts
the contents of the input file in alphabetical order
|
sort
names
|
Sorts
the contents of names in alphabetical order
|
|
Who
|
Tells
you who is logged onto your server
|
who
|
None
|
|
who
am I
|
Tells
you your user information
|
who
am i
whoami
|
None
|
|
Clear
|
Clears
the window and the line buffer
|
clear
|
None
|
|
echo
whatever I type
|
Writes
whatever I type to the screen.
|
echo
hey you!
|
Writes
hey you! to the screen
|
|
banner
big words
|
Does
the same thing as echo only in BIG words
|
banner
hey!
|
Writes
hey! in large letters on the screen
|
|
cat
file1 file2 file3
|
Shows
the three files in consecutive order as one document (can be used to combine
files)
|
cat
cheese milk
|
This
prints the cheese file to the screen first and immediately follows it
with the milk file.
|
|
df
system
|
Reports
the number of free disk blocks
|
df
~
df
$HOME
|
Both
commands will print the total kb space, kb used, kb available, and %used on
the home system (your system).
|
|
head
file
|
Prints
the first 10 lines of the file to the screen
|
head
addresses
|
Prints
the first 10 lines of addresses to the screen
|
|
Number
of lines can be modified
|
head
-25 addresses
|
Prints
the first 25 lines of addresses to the screen
|
||
tail
file
|
Prints
the last 10 lines of the file to the screen
|
tail
test.txt
|
Prints
the last 10 lines of test.txt to the screen
|
|
Number of lines can be modified here, too
|
tail
-32 test.txt
|
Prints
the last 32 lines of test.txt to the screen
|
||
more
input
|
This
prints to screen whatever is input—useful because it only shows one screen at
a time.
|
more
groceries
|
This
will list the groceries file to the screen.
|
|
scroll bar continues to the next screen
|
||||
return moves one line forward
|
||||
Q quits
|
||||
G
goes to the end
|
||||
1G
goes to the beginning
|
||||
Ctrl
u moves up ½ screen
|
||||
Ctrl
d moves down ½ screen
|
ls (-option-optional)
|
Lists all the nonhidden files and directories
|
ls
|
Lists
all nonhidden files and directories in the current directory
|
|||
ls
bin
|
Lists
all nonhidden files and directories in the bin directory
|
|||||
ls
-l or ll
|
Lists
all nonhidden files and directories in long format
|
ls
-l
ll
|
Lists
all nonhidden files and directories in the current directory in long format
|
|||
ls
-l work
ll
work
|
Lists
all nonhidden files and directories in the work directory in long
format
|
|||||
ls
–a
|
Lists
all files and directories including hidden ones
|
ls
-a
|
Lists
all files and directories, including hidden, in the current directory
|
|||
ls
-a temp
|
Lists
all files and directories in the temp directory.
|
|||||
ls
–r
|
Lists
all files and directories in reverse alphabetical order
|
ls
-r
|
Lists
all nonhidden files and directories in the current directory in reverse
alphabetical order
|
|||
ls
-r abc
|
Lists
all nonhidden files and directories in the abc directory in reverse
alphabetical order
|
|||||
ls
–t
|
Lists
all nonhidden files in the order they were last modified
|
ls
-t
|
Lists
all the nonhidden files in the current directory in the order they were last
modified from most recent to last
|
|||
ls
-t work
|
Lists
all the nonhidden files in the work directory in the order they were
last modified from most recent to last
|
|||||
NOTE: Options can be
combined using ls
|
ls -al
|
Lists all files (including hidden (-a)) in long format
(-l)
|
||||
Important Characters
|
>
>>
&
~
<
|
“pipe”
directs the output of the first command to the input of another.
Sends
the output of a command to a designated file
Appends
the output of a command to a designated file
Runs
command in the background; you can still work in the window
Designates
the home directory ($HOME)
Designates
input from somewhere other than terminal
|
ls
-l | more
ls
-l > myfiles
ls
-l >> allfiles
xclock
&
echo
~
progA
< input1
|
Lists
your files in long format one screen at a time
Prints
your listing to a file named myfiles
Appends
your filenames to the end of the allfiles file
Runs
xclock (a clock) allowing you to keep working
Writes
your home directory to the screen
progA
program gets its input from a file named input1
|
|||
Wildcards
*
?
[ ]
|
UNIX
has a set of wildcards that it accepts.
Any
string of characters
Any
one character
Match
any character in the brackets (a hyphen is used for ranges of characters)
|
ls
*.c
ls
file?
ls
v[6-9]file
|
Lists
any file or directory (nonhidden) ending with c
Lists
any file/directory with file and 1 character at the end
Lists
v6file, v7file, v8file, and v9file
|
|||
cd
directory
|
Changes
your current directory to the directory specified
|
cd
bin
|
Changes
directory to the bin directory
|
|||
cd
..
cd
../..
|
Moves
you to the directory that contains the directory you are currently in
Ex.
Current directory=/home/users/bob/bin
execute
cd ..
New
directory= /home/users/bob
or executing cd ../..
New
directory= /home/users.
|
|||||
cd
-
|
Moves
you to the directory you just came from
|
|||||
cd
~
cd
|
Both move you to your
home directory (the directory you start from initially)
|
|||||
mkdir
dirname
|
mkdir
junk
|
Makes a directory
named junk in your current directory
|
||||
mkdir
~/left
|
Makes a directory in
your home directory named left
|
|||||
rm
file1 file2 file3
|
Removes
(deletes) file(s)
|
rm
xyz
|
Deletes
a file named xyz
|
|||
rm
xyz abc
|
Deletes
the files named xyz and abc
|
|||||
rm
*
|
||||||
rm
-i file1 file2
|
Prompts
before deletion of files
*******USE -i AT FIRST*******
|
rm
-i *
|
Prompts
at each nonhidden file and lets you decide whether or not to delete it
|
|||
rm
-f file1 file2
|
Forces
deletion without prompt regardless of permissions
|
rm
-f program
|
Removes
the file program without regard to permissions, status, etc.
|
|||
rm
-r directory
rm
-R directory
|
Remove
a directory along with anything inside of it
|
rm
-r bin
rm
-R bin
|
Each
of these will remove the bin directory and everything inside of it.
|
|||
rmdir
directory
|
Removes
a directory like rm -r does if the directory is empty
|
rmdir
bin
|
Removes
the bin directory if it is empty
|
|||
****dangerous****
rm
-fR name
rm
-Rf name
|
This
combination will force the removal of any file and any directory including
anything inside of it
|
rm
-Rf c_ya
|
Forces
removal without prompts of the c_ya directory and anything inside of
it
|
|||
rm
-Ri directory
|
Deletes
the contents of a directory and the directory if it is empty by prompting the
user before each deletion
|
rm
-Ri rusure
|
Deletes
anything in the directory called rusure that you verify at the prompt,
and if you remove everything in the directory, you will be prompted whether
you want to remove the directory itself or not
|
|||
NOTE: Options can be combined using rm
|
||||||
rmdir
-p directory
|
rmdir -p /home/bin/dir1
|
Deletes
the dir1 directory; if bin directory is empty, it is deleted,
and if home directory is empty it is also deleted
|
||||
cp
file1 newname
|
Copies
a file (file1) and names the copy the new name (newname)
|
cp
old new
|
Makes
a copy of the file/directory named old and names the copy new,
all within the current directory
NOTE: If you copy a file to a newfile name and newfile
already exists, the newfile contents will be overwritten.
|
cp
file dir2/
|
Places
a copy of file in dir2/ and it retains its original name
|
||
cp
../dir1/* .
|
Copies
everything from the dir1 directory located just below where you
currently are and places the copy “here” ( . ) in your current
directory
|
||
cp
-p name target
|
Preserves
all permissions in the original to the target
|
cp
-p execut1 execut2
|
Copies
execut1 executable file and calls the copy execut2, which also
has executable permissions
|
cp
-R directory target
|
Copies
a directory and names the copy the new name (target)
|
cp
-R old/ junk/
|
Makes
a copy of the directory named old and names the directory copy junk
|
cp
-f name target
|
Forces
existing pathnames to be destroyed before copying the file
|
none
|
No
example or description needed
|
mv
initial final
|
Renames
files and directories
|
mv
temp script_1
|
Renames
the file (or directory) temp to the name script_1 in the
current directory
|
Also
moves files to other directories
|
mv
script.exe ~/bin
|
Moves
the script.exe file to the bin directory that is in the home (~)
parent directory and it keeps its initial name
|
|
You
can do multiple moves.
|
mv
script_1 script.exe ~/bin
|
Moves
both script_1 and script.exe to the bin directory
|
|
Pwd
|
Prints
the current directory to the screen
|
pwd
|
May
print something like “/home/bob”
|
pr
(option) filename
|
Prints
the specified file to the default printer (options are not required but can
be combined in any order)
|
pr
userlist
|
Prints
the contents of userlist to the default printer
|
pr
+k filename
|
Starts
printing with page k
|
pr
+5 userlist
|
Prints
the contents of userlist starting with page 5
|
pr
-k filename
|
Prints
in k columns
|
pr
-2 userlist
|
Prints
the contents of userlist in 2 columns
|
pr
-a filename
|
Prints
in multicolumns across the page (use with -k)
|
pr
-3a userlist1
|
Prints
userlist in three columns across the page
|
pr
-d filename
|
Prints
in double space format
|
pr
-d userlist
|
Prints
userlist with double space format
|
pr -h “header” filename
|
Prints
the file with a specified header rather than the filename
|
pr
-h “users” userlist
|
Prints
userlist with users as the header
|
NOTE: Options can be combined using pr
|
lpconfig
printer_id queue
|
Configures remote printers to a local
print queue
|
lpconfig
prntr1 bobprt
|
Configures a printer
named prntr1 to accept print requests from a local queue named bobprt
|
||||
lpconfig
-r queue
|
Removes
the said queue from the local system
|
lpconfig
-r bobprt
|
Removes bobprt
queue from the local system if the person removing the queue is the
owner or “root”
|
||||
lpconfig
-d queue
|
Makes
the said queue the default queue
|
lpconfig
-d vpprnt
|
Makes vpprnt
the default print queue
|
||||
lpstat
(-options)
|
Prints
printer status information to screen (options not required)
|
lpstat
|
Prints status of all
requests made to the default printer by the current server
|
||||
lpstat
-u“user1, user2”
|
Prints
the status of requests made by the specified users
|
lpstat
-u“bob”
|
Prints
status of all requests made by the user with the id bob
|
||||
lpstat
s
|
Prints
the queues and the printers they print to
|
none
|
None
|
||||
lpstat
–t
|
Shows
all print status information
|
none
|
None
|
||||
lpstat
–d
|
Shows
the default printer for the lp command
|
none
|
None
|
||||
lpstat
–r
|
Lets
you know if the line printer scheduler is running
|
none
|
None
|
||||
lp
(-option) file(s)
|
Like
pr, this prints designated files on the connected printer(s) (options not
required and options may be combined).
|
lp
junkfile
|
Prints
the file junkfile to the default printer in default one-sided,
single-sided, single-spaced format
|
||||
lp
-ddest file(s)
|
Prints
the file(s) to a specific destination
|
lp
-dbobsq zoom
|
Sends
the file zoom to the bobsq print queue to print
|
||||
lp
-nnumber file(s)
|
Allows
user to designate the number of copies to be printed
|
lp
-n5 crash
|
Prints
five copies of crash in default settings
|
||||
lp
-ttitle file(s)
|
Places
title on the banner page
|
lp
-tBobs cash
|
Prints
Bobs on the banner page of the file printout named cash
|
||||
lp
-ooption file(s)
|
lp
-od output
|
Prints
the output file double-sided on the printout
|
|||||
lp
-obold output
|
Prints
output in bold print
|
||||||
lp
-ohalf output
|
Divides
the paper into two halves for printing output
|
||||||
lp
-oquarter output
|
Prints
four pages of output per side of paper
|
||||||
lp
-olandscape output
|
Prints
output in landscape orientation
|
||||||
lp
-oportrait output
|
Prints
output in portrait orientation
|
||||||
NOTE: Options can be combined using lp
|
|||||||
cancel
request_id
|
Stops
print jobs or removes them from the queue (request_ids are obtained
using lpstat)
|
cancel
5438
|
Stops
the print job with the id 5438 whether it is printing or if it is
sitting in the queue
|
||||
cancel
-a printer
|
Removes
all print requests from the current user on the specified printer
|
cancel
-a bobsprt
|
Removes
all the requests from the current user to the printer named bobsprt
|
||||
cancel
-u login_id
|
Removes
any print requests queued belonging to the user
|
cancel
-u bob
|
Cancels
all queued print requests for user bob
|
||||
Ps
|
ps
|
Shows
a listing of process IDs, terminal identifier, cumulative execution time, and
command name
|
||
ps
–e
|
Shows
information about all processes
|
ps
-e
|
Shows
a listing of process IDs, terminal identifiers, cumulative execution time,
and command names for all processes
|
|
ps
–f
|
Shows
a full listing of information about the processes listed
|
Shows
UID (user or owner of the process), PID (process ID--use this number to kill
it), PPID (process ID of the parent source), C (processor utilization for
scheduling), STIME (start time of the process), TTY (controlling terminal for
the process), TIME (cumulative time the process has run), and COMMAND (the
command that started the process)
|
||
ps
-u user_id
|
Shows
all processes that are owned by the person with the pertinent user_id
|
ps
-u bob
|
Shows
all the processes that belong to the person with the userid bob
|
|
ps
–ef
|
Shows
all processes in a full listing
|
ps
-ef
|
Shows
all current processes in full listing
|
|
kill
process_id
|
Stops
the process with the said id
|
kill
6969
|
Kills
the process with PID 6969
|
|
kill
-9 process_id
|
Destroys
the process with the said id
|
kill
-9 6969
|
PID
# 6969 doesn’t have a chance here.
|
|
grep
string file
|
Searches
input file(s) for specified string and prints the line with matches
|
grep
mike letter
|
Searches
for the string mike in the file named letter and prints any
line with mike in it to the screen
|
|
grep
-c string file
|
Searches
and prints only the number of matches to the screen
|
grep
-c hayes bankletter
|
Searches
the file bankletter for the string hayes and prints the number
of matches to the screen
|
|
grep
-i string file
|
Searches
without regard to letter case
|
grep
-i hi file1
|
Searches
file1 for hi, Hi, hI, and HI and prints
all matches to the screen
|
|
grep
-n string file
|
Prints
to the screen preceded by the line number
|
grep
-n abc alpha
|
Searches
alpha for abc and prints the matches’ lines and line numbers to
the screen
|
|
grep
-v string file
|
All
lines that do not match are printed
|
grep
-v lead pencils
|
Prints
all lines in pencils that do not contain the string lead
|
|
grep
-x string file
|
Only
exact matches are printed
|
grep
-x time meetings
|
Prints
only lines in meetings that match time exactly
|
|
grep
is useful when you use it in a | “pipe”
|
ps
-ef | grep bob
|
Finds
all processes in full listing and then prints only the ones that match the
string bob to the screen
|
||
You
can also redirect its output to a file.
|
grep
-i jan b_days>mymonth
|
Searches
the file b_days for case-insensitive matches to jan and places
the matching lines into a file called mymonth
|
||
vuepad
filename
|
Opens
filename for editing/viewing in the vuepad editor
|
none
|
None
|
vi
filename
|
Text
editor that exists on every UNIX system in the world
|
none
|
None
|
emacs
filename
|
Another
text editor
|
none
|
None
|
compress
filename
|
Compresses
the file to save disk space.
|
none
|
None
|
uncompress
filename
|
Expands
a compressed file
|
none
|
None
|
Awk
|
UNIX
programming language
|
none
|
None
|
eval
`resize`
|
Tells
the target computer that you’ve resized the window during telnet
|
none
|
None
|
chexp
# filename
|
Keeps
the file(s) from expiring (being erased) on the target computer for # days
|
chexp
365 nr*
|
Keeps
the target computer from deleting all files starting with nr for 1
year (365 days)
|
chexp
4095 nr*
|
Makes
all files whose name starts with nr never expire or be deleted
(infinite)
|
||
Qstat
|
qstat
|
Shows
the status of the requests submitted by the invoker of the command—this will
print request-name, request-id, the owner,
relative request priority, and request state (is it running yet?)
|
|
qstat
-a
|
Shows
all requests
|
||
qstat
-l
|
Shows
requests in long format
|
||
qstat
-m
|
Shows
requests in medium-length format
|
||
qstat
-u bob
|
Shows
only requests belonging to the user bob
|
||
qstat
-x
|
Queue
header is shown in an extended format
|
||
xterm
xterm
-option
xterm
+option
|
Opens
a new window (x-terminal) for you to work
-option
sets the option
+option
resets the option to default
|
This
opens another window like the one you are currently working in.
USING XTERM WILL ELIMINATE A LOT OF DESKTOP CLUTTER. I
STRONGLY SUGGEST YOU LEARN TO USE IT IN YOUR SCRIPTS.
|
|
xterm
-help
|
Displays
the xterm options
|
xterm
-help
|
Shows
the options available
|
xterm
-e program
|
xterm
-e myprog.exe
|
This
opens an xterm window and executes the program myprog.exe from that
window so that you may still work in your present window.
|
||
xterm
-sb
|
Opens
an xterm that saves a set number of lines when they go off the top of the
page and makes them accessible with a scroll bar
|
xterm
-sb
|
Puts
a scroll bar on the right side of the page for reviewing past lines in the
window
NOTE:
When clicking in the scroll bar, the left button scrolls down, the right
scrolls up, and the middle snaps the scroll bar to the mouse position for
dragging up and down.
|
|
xterm
-sl number
|
Specifies
the number of lines to be saved once they go off the top of the screen
(default is 64)
|
xterm
-sl 1000
|
The
xterm will save 1,000 lines of work once it has moved off the
immediate viewing area; it can be accessed using the scroll bar.
|
|
xterm
-geom xxy+px+py
|
This
option allows you to specify the size x pixels by y pixels and
placement position x by position y of the new window when it
opens.
Position
+0+0 is the top left-hand corner of the screen, and the bottom right is
approx. +1200+1000 depending on your resolution.
Note:
The size of the window takes precedence over position, so if you position it
too close to the side of the screen, it will position at the edge with the
correct size.
|
xterm
-geom 80x80+0+50
xterm
-geom 10x35+300+500
xterm
-geom 5x5+0+0
|
The
first command will open a window 80 pixels wide by 80 pixels
tall and position its top left-hand corner at 0 pixels to the right of
the left edge and 50 pixels down from the top of the screen.
The
second command will open a window 10 pixs wide by 35 pixs tall
and position its top left-hand corner 300 pixs from the left edge and 500
pixs down from the top.
The
third command will make a 5 by 5 window and position its top
left-hand corner at the top left-hand corner of the screen.
xterm will not compromise size when positioning.
|
|
xterm
-title label
|
Allows
you to label your window’s top title bar
|
xterm
-title SCRIPTS
|
Opens
an xterm window with the title SCRIPTS (default is whatever follows
the -e option)
|
|
xterm
-(areas) color
|
Allows
you to modify different colors in your xterm window
|
xterm -bg white
xterm
-bd huntergreen
xterm
-fg red
|
The
first command sets the background color to white.
The
second command sets the window border color to huntergreen.
The
third command window sets the text color to red.
|
|
xterm
-fn font
|
Sets
the font in the new xterm window
|
xterm
-fn courr18
|
Sets
the font to courr18 (default is fixed)
|
|
xterm
-iconic
|
Starts
the new xterm as an icon (double-click to maximize)
|
xterm
-iconic -title xyz
|
Opens
an xterm in iconic form with the title xyz
|
|
NOTE: Options can be combined using xterm
|
||||
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