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Mac OS X Terminal Commands list

An A-Z Index of the Apple OS X command line (TERMINAL)
The tcsh command shell of Darwin (the open source core of OSX)
aliasCreate an alias
allocList used and free memory awk Find and Replace text within file(s) basenameConvert a full pathname to just a folder path bash Bourne-Again SHell (Linux)
blessSet volume bootability and startup disk options.
breakExit from a loop
cal Display a calendar case Conditionally perform a command cat Display the contents of a file cd Change Directory
chflagsChange a file or folder's flags.
chgrpChange group ownership
chmod
Change access permissions
chownChange file owner and group
chrootRun a command with a different root directory
cksumPrint CRC checksum and byte counts
clearClear terminal screen
cmp
Compare two files comm Compare two sorted files line by line
completeEdit a command completion [word/pattern/list]
continueResume the next iteration of a loop
cp
Copy one or more files to another location cron Daemon to execute scheduled commands
crontabSchedule a command to run at a later date/time
cut
Divide a file into several parts date Display or change the date & time dc Desk Calculator dd Data Dump - Convert and copy a file df Display free disk space diff Display the differences between two files
diff3Show differences among three files
dig
DNS lookup
dirnameConvert a full pathname to just a path
dirs
Display list of remembered directories
diskutilDisk utilities - Format, Verify, Repair
dittoCopy files and folders
dscl
Directory Service command line utility du Estimate file space usage echo Display message on screen ed A line-oriented text editor (edlin)
enableStop or start printers and classes.
env
Set environment and run a utility eval Evaluate several commands/arguments exec Execute a command exit Exit the shell expectProgrammed dialogue with interactive programs Also see AppleScript
expandConvert tabs to spaces
expr
Evaluate expressions falseDo nothing, unsuccessfully
fdiskPartition table manipulator for Darwin UFS/HFS/DOS
find
Search for files that meet a desired criteria fmt Reformat paragraph text fold Wrap text to fit a specified width for Expand words, and execute commands
foreachLoop, expand words, and execute commands
fsck
Filesystem consistency check and repair
fsaclctlFilesystem enable/disable ACL support
fs_usageFilesystem usage (process/pathname)
ftp Internet file transfer program GetFileInfo Get attributes of HFS+ files
getoptParse positional parameters
goto
Jump to label and continue execution grep Search file(s) for lines that match a given pattern
groupsPrint group names a user is in
gzip
Compress or decompress files head Display the first lines of a file hdiutilManipulate iso disk images history Command History hostnamePrint or set system name id Print user and group names/id's
if Conditionally perform a command info Help info installCopy files and set attributes jobs List active jobs join Join lines on a common field kill Stop a process from running l List files in long format (ls -l) ll List files in long format, showing invisible files (ls -la) less Display output one screen at a time ln Make links between files (hard links, symbolic links) locate Find files lognamePrint current login name login log into the computer
logoutExit a login shell (bye)
lpr
Print files lprm Remove jobs from the print queue
lpstatPrinter status information
ls
List information about file(s)
lsbomList a bill of materials file
lsof
List open files man Help manual
mkdirCreate new folder(s)
mkfifoMake FIFOs (named pipes)
more
Display output one screen at a time
mountMount a file system
mv
Move or rename files or directories net Manage network resources nice Set the priority of a command nohupRun a command immune to hangups onintrControl the action of a shell interrupt open Open a file/folder/URL/Application osascript Execute AppleScript passwdModify a user password
pasteMerge lines of files
pbcopyCopy data to the clipboard
pbpastePaste data from the Clipboard pico Simple text editor ping Test a network connection
pmsetPower Management settings
popd
Restore the previous value of the current directory pr Convert text files for printing
printenvPrint environment variables
printfFormat and print data
ps
Process status
pushdSave and then change the current directory
pwd
Print Working Directory quotaDisplay disk usage and limits rcp Copy files between machines. repeatExecute a command multiple times rm Remove files rmdir Remove folder(s) rpm Remote Package Manager rsyncRemote file copy - Sync file tree (also RsyncX) say Convert text to audible speech
schedSchedule a command to run at a later time.
screencapture Capture screen image to file or disk
sdiffMerge two files interactively
securityAdminister Keychains, keys, certificates and the Security
framework
sed
Stream Editor set Set a shell variable = value
setenvSet an environment variable = value
setfileSet attributes of HFS+ files
shiftShift positional parameters
shutdownShutdown or restart OS X
sleepDelay for a specified time
softwareupdate System software update tool
sort
Sort text files
splitSplit a file into fixed-size pieces
stop
Stop a job or process su Substitute user identity sudo Execute a command as another user sum Print a checksum for a file switchConditionally perform a command
tail Output the last part of files tar Tape ARchiver tee Redirect output to multiple files test Condition evaluation
textutilManipulate text files in various formats
time
Measure Program Resource Use
touchChange file timestamps
traceroute Trace Route to Host
tr
Translate, squeeze, and/or delete characters true Do nothing, successfully tty Print filename of terminal on stdin type Describe a command umaskUsers file creation mask umount a device unaliasRemove an alias
unamePrint system information
unexpandConvert spaces to tabs
uniq
Uniquify files
unitsConvert units from one scale to another
unsetRemove variable or function names
unsetenvRemove environment variable
usersPrint login names of users currently logged in
uuencodeEncode a binary file
uudecodeDecode a file created by uuencode
vi
Text Editor wc Print byte, word, and line counts
whereReport all known instances of a command
whichLocate a program file in the user's path
while Execute commands who Print all usernames currently logged on whoamiPrint the current user id and name (`id -un') xargsExecute utility - passing arguments yes Print a string until interrupted 

Note: tcsh is the default shell in OS X Jaguar (10.2)
Panther (10.3) and Tiger (10.4) default to bash - many commands
do work in either shell, but this page will soon be updated to list
the bash syntax.