Unix Commands
Unix Commands
Unix
January 2003
This quick reference lists commands, including a syntax diagram
2. Commands
and brief description. […] indicates an optional part of the
2.1. Command-line Special Characters
command. For more detail, use:
Quotes and Escape
man command
Join Words
"…"
Use man tcsh for the command language.
Suppress Filename, Variable Substitution
'…'
Escape Character
\
1. Files
Separation, Continuation
1.1. Filename Substitution
Command Separation
;
Wild Cards
? *
Command-Line Continuation (at end of line)
\
Character Class (c is any single character)
[c…]
2.2. I/O Redirection and Pipes
Range
[c-c]
Home Directory
~
Standard Output
>
Home Directory of Another User
~user
(overwrite if exists)
>!
List Files in Current Directory
ls [-l]
Appending to Standard Output
>>
List Hidden Files
ls -[l]a
Standard Input
<
Standard Error and Output
>&
1.2. File Manipulation
Standard Error Separately
Display File Contents
cat filename
( command > output ) >& errorfile
Copy
cp source destination
Pipes/ Pipelines
command | filter [ | filter]
Move (Rename)
mv oldname newname
Filters
Remove (Delete)
rm filename
Word/Line Count
wc [-l]
Create or Modify file
pico filename
Last n Lines
tail [-n]
Sort lines
sort [-n]
1.3. File Properties
Multicolumn Output
pr -t
Seeing Permissions
ls -l filename
List Spelling Errors
ispell
Changing Permissions
chmod nnn filename
chmod c=p…[,c=p…] filename
2.3. Searching with grep
n, a digit from 0 to 7, sets the access level for the user
grep Command
grep "pattern " filename
(owner), group, and others (public), respectively. c is one of:
command | grep "pattern "
u–user; g–group, o–others, or a–all. p is one of: r–read
Search Patterns
access, w–write access, or x–execute access.
beginning of line
^
Setting Default Permissions
umask ugo
end of line
$
ugo is a (3-digit) number. Each digit restricts the default
any single character
.
permissions for the user, group, and others, respectively.
single character in list or range
[…]
Changing Modification Time
touch filename
character not in list or range
[^…]
Making Links
ln [-s] oldname newname
zero or more of preceding char. or pattern
*
Seeing File Types
ls -F
zero or more of any character
.*
escapes special meaning
\
1.4. Displaying a File with less
Run less
less filename
3. C-Shell Features.
Next line
RETURN
3.1 History Substitution
Next Page
SPACE
Previous line
k
Repeat Previous Command
!!
Previous Page
b
Commands Beginning with str
!str
Commands Containing str
!?str[?]
1.5. Directories
All Arguments to Prev. Command
!*
Change Directory
cd directory
Word Designators
Make New Directory
mkdir directory
All Arguments
:*
Remove Directory
rmdir directory
Last Argument
:$
Print Working (Show Current) Directory
pwd
First Argument
:^
n'th Argument
:n
Arguments x Through y
:x-y
Standard Commands
whereis file
Modifiers
Aliases and Commands
which command
Print Command Line
:p
Describe Command
whatis command
Substitute Command Line
:[g]s/l/r/
Searching Out Files
find dir -name name -print
dir is a directory name within which to search.
3.2 Aliases
name is a filename to search for.
alias Command
alias name 'definition'
6.2. Finding Changes
definition can contain escaped history substitution
event
and
Comparing Files
diff leftfile rightfile
word designators as placeholders for command-line arguments.
diff prefixes a less-than (<) to selected lines from leftfile
and a greater-than (>) to lines from rightfile.
3.3. Variable Substitution
6.3. Automating Tasks
Creating a Variable
set var
Assigning a Value
set var = value
Create a Makefile
pico Makefile
Expressing a Value
$var
A makefile consists of macro definitions and targets.
Displaying a Value
echo $var
Test Makefile
make -n [target]
value is a single word, an expression in quotes, or an
Run make
make [target]
expression that results in a single word after variable,
6.4. Managing Disk Usage
filename and command substitution takes place.
Assigning a List
set var = (list)
Check Quota
quota -v
list is a space-separated list of words, or an expression that
Seeing Disk Usage
df
results in a space-separated list.
du -s
Selecting the n'th Item
$var[n]
6.5. Combining and Compressing Files
Selecting all Items
$var
Create a tarfile
tar cf file.tar file1 file2 … fileN
Selecting a Range
$var[x-y]
tar combines files but does not compress
Item Count
$#var
Create a zipfile
zip filename
3.4 foreach Lists
Unzip a file
unzip filename
Start foreach Loop
foreach var (list)
7. Printing
foreach prompts for commands to repeat for each item in
list (with >), until you type end. Within
the loop, $var
7.1 Formatting Output for Printing
stands for the current item in list.
Paginate with Page Headers
pr filename
in n columns
pr -n filename
3.5. Command Substitution
Format for Laser Printer
tex document
Replace Command with its Output on Command Line
`…`
7.2 The Printer Queue
3.6 Job Control
Print a File
lp [-dpr] filename
Run Command in the Background
&
lpcae filename
Stop Foreground Job
CTRL-Z
Check Quota
lpquot
List of Background Jobs
jobs
List Queue
lpq
Bring Job Forward
%[n]
Stop Job
lprm
Resume Job in Background
%[n] &
8. Miscellaneous
4. Processes
8.1 Miscellaneous Commands
Listing
ps [-[ef]]
List Commands for Subject
man -k subject
Terminating
kill [-9] PID
Display Current Date and Time
date
Timing
time command
Log off
exit
time is a number up to 4 digits. script is the name
of a file
containing the command line(s) to perform.
Electronic Mail
pine
Display Documentation
man command
5. Users
8.2 Control Keys
Seeing Who is Logged In
who
Abort Program
CTRL-C
w
Backspace (Delete Last Character)
CTRL-H
Seeing Your User Name
whoami
Pause Display on Screen
CTRL-S
Resume Display after CTRL-S
CTRL-Q
6. Managing Files
Send Job to Background
CTRL-Z followed by bg
6.1. Looking Up Files
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1410 Engineering Drive, or to: editor@engr.wisc.edu
