Create an alias. Aliases allow a string to be substituted for a word. An alias can be used as the first word of any simple command.

alias [-p] [name[=value] ...]

unalias [-a] [name...]

-p Print the current values

-a Remove All aliases

When arguments are supplied, an alias is defined for each name whose value is given. A trailing space in value causes the next word to be checked for alias
substitution when the alias is expanded.

If no value is given, (or with the -p option) alias will print a list of Aliases along with their current values. For each name in the argument list for which no value is supplied, the name and value of the alias is printed.

Alias returns true unless a name is given for which no alias has been defined.

name can not be `alias’ or `unalias’.

unalias can be used to remove each name from the list of defined aliases.

Alias substitution
The shell maintains a list of aliases which can be set, unset and printed by the alias and unalias commands. After a command line is parsed into simple commands the first word of each command, left-to-right, is checked to see if it has an alias. If so, the first word is replaced by the alias. If the alias contains a history reference, it undergoes History substitution (q.v.) as though the original command were the previous input line. If the alias does not contain a history reference, the argument list is left untouched.

Thus if the alias for ls were ls -l the command ls /usr would become ls -l /usr, the argument list here being undisturbed. If the alias for lookup were grep !^ /etc/passwd‘ then lookup bill would become grep bill /etc/passwd.

Aliases can be used to introduce parser metasyntax. For example, alias print ‘pr !* | lpr’ defines a command (print) which pr‘s its arguments to the line printer.

The first word of the replacement text is tested for aliases, but a word that is identical to an alias being expanded is not expanded a second
time. This means that you can alias ls to ls -F, for instance, and bash does not try to recursively expand the replacement text.


Create an alias ‘c’ that will clear the screen:
$ alias c=’clear’

Create an alias ‘ls’ that will change the default action of ls:
$ alias ls=’ls –classify’
$ ls
$ unalias ls

More aliases for ls:
$ alias la=’ls -lAXh –color=always’   #Show all, sort by extension
$ alias ls-al=’ls -al’   #fix typo missing space
$ alias l=”ls -l”
$ alias la=”ls -la”

Use alias to fix missing space typos:
$ alias cd..=’cd ..’
alias ..=’cd ..’

Display the working directory
$ alias .=’echo $PWD’

Prevent accidental deletions by making rm interactive:
$ alias rm=’rm -i’

Shorten apt-get installation commands:
$ alias canhaz=’sudo apt-get install’

Run firefox and open a specific website:
$ alias fftr=’/Applications/’

Produce a custom prompt to display which machine you are on, the current folder, and the number of the current command:

   $ alias cd='cd !*; set currDir = `basename $cwd`; set currDir = `echo
" ! >"`; set prompt = "${currDir} "'
$ cd $cwd

<Mac_One:Work-folder 15 >

Making an alias permanent:

Assuming you have the BASH shell, then use your favorite text editor to edit or create a file called ~/.bash_aliases and add your alias commands.

alias is a bash built-in command.

“There are many reasons why novelists write, but they all have one thing in common – a need to create an alternative world” ~ John Fowles


Alias man page –
env – Display, set, or remove environment variables
echo – Display message on screen
set – Set a shell variable
shift – Shift positional parameters

Apple OS X command line

An A-Z Index of the Apple OS X command line

You can get more from


  alias     Create an alias •
alloc List used and free memory
apropos Search the whatis database for strings
asr Apple Software Restore
awk Find and Replace text within file(s)
basename Convert a full pathname to just a filename
bash Bourne-Again SHell
bg Send to background •
bind Display readline key and function bindings •
bless Set volume bootability and startup disk options
break Exit from a For, While, Until or Select loop •
builtin Execute a shell builtin •
bzip2 Compress or decompress files
cal Display a calendar
calendar Reminder Service
caller Return the context of a subroutine call •
case Conditionally perform a command •
cat Concatenate and print (display) the content of files
cd Change Directory •
chflags Change a file or folder's flags
chgrp Change group ownership
chmod Change access permissions
chown Change file owner and group
chroot Run a command with a different root directory
cksum Print CRC checksum and byte counts
clear Clear terminal screen
cmp Compare two files
comm Compare two sorted files line by line
command Run a command (not a function) •
complete Edit a command completion [word/pattern/list] •
continue Resume the next iteration of a loop •
cp Copy one or more files to another location
cron Daemon to execute scheduled commands
crontab Schedule a command to run at a later date/time
csplit Split a file into context-determined pieces
curl Transfer data from or to a server
cut Divide a file into several parts
date Display or change the date & time
dc Desk Calculator
dd Convert and copy a file, clone disks
declare Declare variable & set attributes •
defaults Set preferences, show hidden files
df Display free disk space
diff Display the differences between two files
diff3 Show differences among three files
dig DNS lookup
dirname Convert a full pathname to just a path
dirs Display list of remembered directories •
diskutil Disk utilities - Format, Verify, Repair
disown Unbind a job from the current login session •
ditto Copy files and folders
dot_clean Remove dot-underscore files
drutil Interact with CD/DVD burners
dscacheutil Query or flush the Directory Service/DNS cache
dseditgroup Edit, create, manipulate, or delete groups
dsenableroot Enable root access
dsmemberutil View user and groups rights
dscl Directory Service command line utility
du Estimate file space usage
echo Display text on screen •
ed A line-oriented text editor (edlin)
enable Enable and disable builtin shell commands •
env List or Set environment variables
eval Evaluate several commands/arguments •
exec Execute a command •
exit Exit the shell •
expand Convert tabs to spaces
expect Programmed dialogue with interactive programs
Also see AppleScript
export Set an environment variable •
expr Evaluate expressions
false Do nothing, unsuccessfully
fc Fix command (history)
fdisk Partition table manipulator for Darwin UFS/HFS/DOS
fg Send job to foreground •
file Determine file type
find Search for files that meet a desired criteria
fmt Reformat paragraph text
fold Wrap text to fit a specified width
for Loop command •
fsck Filesystem consistency check and repair
fsaclctl Filesystem enable/disable ACL support
fs_usage Filesystem usage (process/pathname)
ftp Internet file transfer program
function Define Function Macros
GetFileInfo Get attributes of HFS+ files
getopt Parse positional parameters
getopts Parse positional parameters •
goto Jump to label and continue execution
grep Search file(s) for lines that match a given pattern
groups Print group names a user is in
gzip Compress or decompress files
halt Stop and restart the operating system
hash Refresh the cached/remembered location of commands •
head Display the first lines of a file
hdiutil Manipulate iso disk images
history Command History •
hostname Print or set system name
iconv Convert the character set of a file
id Print user and group names/id's
if Conditionally perform a command •
ifconfig Configure network interface parameters
ipconfig View and control IP configuration state
info Help info
install Copy files and set attributes
jobs List active jobs •
join Join lines on a common field
kextfind List kernel extensions
kickstart Configure Apple Remote Desktop
kill Kill a process by specifying its PID
killall Kill processes by name
l List files in long format (ls -l)
last Indicate last logins of users and ttys
launchctl Load or unload daemons/agents
ll List files in long format, showing invisible files (ls -la)
less Display output one screen at a time
let Evaluate expression •
lipo Convert a universal binary
ln Make links between files (hard links, symbolic links)
local Set a local (function) variable •
locate Find files
logname Print current login name
login log into the computer
logout Exit a login shell (bye) •
look Display lines beginning with a given string
lpr Print files
lprm Remove jobs from the print queue
lpstat Printer status information
ls List information about file(s)
lsregister Reset the Launch Services database
lsbom List a bill of materials file
lsof List open files
man Help manual
mdfind Spotlight search
mdutil Manage Spotlight metadata store
mkdir Create new folder(s)
mkfifo Make FIFOs (named pipes)
more Display output one screen at a time
mount Mount a file system
mv Move or rename files or directories
nano Simple text editor
net Manage network resources
netstat Show network status
networksetup Network and System Preferences
nice Set the priority of a command
nohup Run a command immune to hangups
ntfs.util NTFS file system utility
onintr Control the action of a shell interrupt
open Open a file/folder/URL/Application
opensnoop Snoop file opens as they occur
osacompile Compile Applescript
osascript Execute AppleScript
passwd Modify a user password
paste Merge lines of files
pbcopy Copy data to the clipboard
pbpaste Paste data from the Clipboard
ping Test a network connection
pkill Kill processes by a full or partial name
pkgutil Query and manipulate installed packages
plutil Property list utility
pmset Power Management settings
popd Restore the previous value of the current directory •
pr Convert text files for printing
printenv List environment variables
printf Format and print data •
ps Process status
pushd Save and then change the current directory
pwd Print Working Directory •
quota Display disk usage and limits
rcp Copy files between machines
read Read one line from standard input •
readonly Mark a variable or function as read-only •
reboot Stop and restart the system
return Exit a function •
rev Reverse lines of a file
rm Remove files
rmdir Remove folder(s)
rpm Remote Package Manager
rsync Remote file copy - Sync file tree
say Convert text to audible speech
screen Multiplex terminal, run remote shells via ssh
screencapture Capture screen image to file or disk
scutil Manage system configuration parameters
sdiff Merge two files interactively
security Administer Keychains, keys, certificates and the Security framework
sed Stream Editor
select Generate a list of items •
set Set a shell variable = value •
setfile Set attributes of HFS+ files
shasum Print or Check SHA Checksums
shift Shift positional parameters •
shopt Set shell options •
shutdown Shutdown or restart OS X
sips Scriptable image processing system
sleep Delay for a specified time
softwareupdate System software update tool
sort Sort text files
source Execute commands from a file •
split Split a file into fixed-size pieces
srm Securely remove files or directories
stat Display the status of a file
stop Stop a job or process
su Substitute user identity
sudo Execute a command as another user
sum Print a checksum for a file
suspend Suspend execution of this shell •
sw_vers Print Mac OS X operating system version
system_profiler Report system configuration
systemsetup Computer and display system settings
tail Output the last part of files
tar Tape ARchiver
tcpdump Dump traffic on a network
tee Redirect output to multiple files
test Condition evaluation •
textutil Manipulate text files in various formats (Doc,html,rtf)
time Measure Program Resource Use
times Print shell & shell process times •
tmutil Time Machine utility
top Display process information
touch Change file timestamps
tput Set terminal-dependent capabilities, color, position
tr Translate, squeeze, and/or delete characters
trap Execute a command when the shell receives a signal •
traceroute Trace Route to Host
true Do nothing, successfully
tty Print filename of terminal on stdin
type Describe a command •
ufs.util Mount/unmount UFS file system
ulimit limit the use of system-wide resources •
umask Users file creation mask
umount Unmount a device
unalias Remove an alias •
uname Print system information
unexpand Convert spaces to tabs
uniq Uniquify files
units Convert units from one scale to another
unset Remove variable or function names •
until Loop command •
uptime Show how long system has been running
users Print login names of users currently logged in
uuencode Encode a binary file
uudecode Decode a file created by uuencode
uuidgen Generate a Unique ID (UUID/GUID)
uucp Unix to Unix copy
vi Text Editor
wait Wait for a process to complete •
wc Print byte, word, and line counts
whatis Search the whatis database for complete words
whereis Locate a program
which Locate a program file in the user's path
while Loop command •
who Print all usernames currently logged on
whoami Print the current user id and name (`id -un')
write Send a message to another user
xargs Execute utility - passing arguments
xattr Display and manipulate extended attributes
youtube-dl Download video
yes Print a string until interrupted
zip Package and compress (archive) files.
!! Run the last command again

Apple OS X command line