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May 19, 2015 - A Look At The New Commandlinefu
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Maintained by Jon H.

Site originally by David Winterbottom (user root).

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Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

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All commands from sorted by
Terminal - All commands - 12,407 results
echo "-------------" >> nicinfo.txt; echo "computer name x" >> nicinfo.txt; ifconfig | grep status >> nicinfo.txt; ifconfig | grep inet >> nicinfo.txt; ifconfig | grep ether >> nicinfo.txt; hostinfo | grep type >> nicinfo.txt;
2009-06-25 12:32:37
User: miccaman
Functions: echo grep ifconfig type
Tags: Os X ifconfig
-2
Up
Down
get linkspeed, ip-adress, mac-address and processor type from osx

get desired info from machine and pipe it txt file.

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
/usr/dt/bin/dtconfig -d
2009-06-25 09:32:37
User: thesuperjason
1
Up
Down
Disable graphical login on Solaris

With a full installation of Solaris 10, the graphical login and desktop will start by default. This command will disable that feature. To enable it again use: /usr/dt/bin/dtconfig -e

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sudo /Applications/Utilities/Adobe\ Utilities.localized/Adobe\ Updater5/Adobe\ Updater.app/Contents/MacOS/Adobe\ Updater
2009-06-25 08:07:47
User: miccaman
Functions: sudo
Tags: Os X
-9
Up
Down
Adobe Updater Crashes on Mac OS X Fix

adobe updater keeps popping up. (normal update fails, probably due to insufficient rights)

(src: http://aricsblog.blogspot.com/2007/12/adobe-updater-crashes-on-mac-os-x-and.html)

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ctrl + r
2009-06-25 06:51:38
User: Bluehive
9
Up
Down
Search command history on bash

Very handy and time-saving.

Do a 'ctrl+ r' on command prompt. You will see a "(reverse-i-search)`':" mark. Just type any sub-string of the command you want to search(provided you have used it sometime in the same session).

Keep on searching by repeatedly pressing ctrl+r. Press enter once you get the desired command string.

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curl -v -k -u user:password "https://members.dyndns.org/nic/update?hostname=<your_domain_name_here>&myip=$(curl -s http://checkip.dyndns.org | sed 's/[a-zA-Z<>/ :]//g')&wildcard=NOCHG&mx=NOCHG&backmx=NOCHG"
2009-06-24 17:00:15
User: din7
5
Up
Down
Update dyndns.org with your external IP.

This is great if you are behind a router that does not support dynamic dns updates!

Example: AT&T u-verse gateway...

Put this in a script and run it as a cron job.

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echo $numbers | sed "s/\( \|$\)/\n/g" | sort -nu | tr "\n" " " | sed -e "s/^ *//" -e "s/ $//"
2009-06-24 15:12:17
User: chickenzilla
Functions: echo sed sort tr
-1
Up
Down
Sort a list of numbers on on line, separated by spaces.

You can replace "sort -nu" with "sort -u" for a word list sorted or "sort -R" for a random-sorted line

(edit: corrected)

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mii-tool eth0
2009-06-24 08:43:55
User: flart
6
Up
Down
Check if network cable is plugged in and working correctly

with 'mii-tool -w eth0' you can watch the interface for changes of the link status

Show sample output | Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo "${STRING}" | tr '[A-Z]' '[a-z]' | awk '{print toupper(substr($0,1,1))substr($0,2);}'
2009-06-23 21:11:34
User: mohan43u
Functions: awk echo tr
Tags: awk tr
0
Up
Down
String Capitalization

Helpful when we want to do mass file renaming(especially mp3s).

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find . -depth -type d -exec du -s {} \; | sort -k1nr
2009-06-23 20:52:35
User: mohan43u
Functions: du find sort
Tags: sort find du
4
Up
Down
Size(k) of directories(Biggest first)

somewhat faster version to see the size of our directories. Size will be in Kilo Bytes. to view smallest first change '-k1nr' to '-k1n'.

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readlink -f ../super/symlink_bon/ahoy
2009-06-23 17:46:08
User: rbs
Functions: readlink
11
Up
Down
Get the canonical, absolute path given a relative and/or noncanonical path

readlink -f accepts a relative, noncanonical path and emits the corresponding canonical, absolute path.

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tune2fs -O extents,uninit_bg,dir_index /dev/yourpartition
2009-06-23 17:42:01
User: starchox
Functions: tune2fs
Tags: Filesystem ext3 ext4
5
Up
Down
Migrate existing Ext3 filesystems to Ext4

Before doing this, back-up all data on any ext3 partitions that are to be converted to ext4.

After running previous command you MUST run fsck, is needed to return the filesystem to a consistent state.

fsck -pDf /dev/yourpartition

Edit /etc/fstab and change the 'type' from ext3 to ext4 for any partitions that are converted to ext4.

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echo {0..1}{0..1}{0..1}{0..1}
2009-06-23 17:30:20
User: dennisw
Functions: echo
Tags: bash binary ksh zsh decimal array
17
Up
Down
Create a list of binary numbers

If you should happen to find yourself needing some binary numbers, this is a quickie way of doing it. If you need more digits, just add more "{0..1}" sequences for each digit you need. You can assign them to an array, too, and access them by their decimal equivalent for a quickie binary to decimal conversion (for larger values it's probably better to use another method). Note: this works in bash, ksh and zsh. For zsh, though, you'll need to issue a setopt KSH_ARRAYS to make the array zero-based.

binary=({0..1}{0..1}{0..1}{0..1})

echo ${binary[9]}
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ls -1t | head -n10
2009-06-23 12:15:12
User: wires
Functions: head ls
Tags: ls
7
Up
Down
find the 10 latest (modified) files

order the files by modification (thanks stanishjohnd) time, one file per output line and filter first 10

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ditto --arch i386 doubleTwist.app doubleTwist_i386.app
2009-06-22 23:59:14
User: thebillywayne
0
Up
Down
remove unnecessary architecture code from Mac OS X Universal binaries

ditto can be used to "thinnify" Mach-O Universal binaries to separate unncessary code from your machine. For example, doubleTwist.app shaved off around 10 MB while Google Earth went from 112 MB to 62 MB after extracting only the i386 code from them.

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ssh -L :: -L :: @
2009-06-22 19:12:48
User: starchox
Functions: ssh
10
Up
Down
Multiple SSH Tunnels

Thankfully, the ssh command allows you to specify multiple tunnels through the same server in one command.

Remeber if you want a priviliged port on your machine, you must use root or sudo account.

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wget -q --user=<username> --password=<password> 'https://updates.opendns.com/nic/update?hostname=your_opendns_hostname&myip=your_ip' -O -
2009-06-22 18:08:42
User: Alanceil
Functions: wget
Tags: IP OpenDNS Dynamic IP
5
Up
Down
Update your OpenDNS network ip

Intended for dynamic ip OpenDNS users, this command will update your OpenDNS network IP.

For getting your IP, you can use one of the many one-liners here on commandlinefu.

Example:

I use this in a script which is run by kppp after it has successfully connected to my ISP:

---

#!/bin/bash

IP="`curl -s http://checkip.dyndns.org/ | grep -o '[[:digit:].]\+'`"

PW="hex-obfuscated-pw-here"

if [ "$IP" == "" ] ; then echo 'Not online.' ; exit 1

else

wget -q --user=topsecret --password="`echo $PW | xxd -ps -r`" 'https://updates.opendns.com/nic/update?hostname=myhostname&myip='"$IP" -O -

/etc/init.d/ntp-client restart &

fi

---

PS: DynDNS should use a similar method, if you know the URL, please post a comment. (Something with members.dyndns.org, if I recall correctly)

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find . -name "*.sql" -print0 | wc -l --files0-from=-
2009-06-22 17:45:03
User: vincentp
Functions: find wc
Tags: find wc count line
2
Up
Down
Get lines count of a list of files

This command gives you the number of lines of every file in the folder and its subfolders matching the search options specified in the find command. It also gives the total amount of lines of these files.

The combination of print0 and files0-from options makes the whole command simple and efficient.

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multitail /var/log/messages /var/log/apache2/access.log /var/log/mail.info
2009-06-22 06:51:11
User: Neo23x0
4
Up
Down
Watch several log files in a single window

It works like a "tail -f" on several files.

Use the number keys 0-9 to set a baseline in the numbered window.

Pressing "b" let you scroll back in one of the windows.

Comments (5) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
while true; do { $(which logger) -p local4.notice `free -m | grep Mem`; sleep 60; } done &
2009-06-22 00:29:53
User: Neo23x0
Functions: grep sleep which
3
Up
Down
Log the current memory statistics frequently to syslog

Uses logger in a while loop to log memory statistics frequently into the local syslog server.

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bind '"\e[24~"':"\"ps -elF;df -h;free -mt;netstat -lnpt;who -a\C-m"""
2009-06-21 23:57:20
User: Neo23x0
17
Up
Down
Create a system overview dashboard on F12 key

Command binds a set of commands to the F12 key.

Feel free to alter the dashboard according to your own needs.

How to find the key codes?

Type

read

Then press the desired key (example: F5)

^[[15~

Try

bind '"\e[15~"':"\"ssh [email protected]\C-m"""

or

bind '"\e[16~"':"\"apachectl -k restart\C-m"""
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!*
2009-06-21 17:58:01
User: Neo23x0
86
Up
Down
Reuse all parameter of the previous command line

!* is all of the arguments to the previous command rather than just the last one.

This is useful in many situations.

Here's a simple example:

vi cd /stuff

oops!

[exit vi, twice]

!*

expands to: cd /stuff

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# cd $partition; dd if=/dev/zero of=ShredUnusedBlocks bs=512M; shred -vzu ShredUnusedBlocks
2009-06-21 14:17:22
User: mpb
Functions: cd dd shred
8
Up
Down
securely erase unused blocks in a partition

This command securely erases all the unused blocks on a partition.

The unused blocks are the "free space" on the partition.

Some of these blocks will contain data from previously deleted files.

You might want to use this if you are given access to an old computer and you do not know its provenance.

The command could be used while booted from a LiveCD to clear freespace space on old HD.

On modern Linux LiveCDs, the "ntfs-3g" system provides ReadWrite access to NTFS partitions thus enabling this method to also be used on Wind'ohs drives.

NB depending on the size of the partition, this command could take a while to complete.

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sudo sed 's/\o0/\n/g' "/proc/$(pidof -x firefox)/environ" ;# replace firefox
2009-06-21 09:47:02
User: plasticdoc
Functions: sed sudo
3
Up
Down
Show an application's environment variables
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watch -t -n1 "date +%T|figlet"
2009-06-21 01:02:37
User: dennisw
Functions: watch
Tags: Linux terminal unix shell date time figlet watch
45
Up
Down
Display a cool clock on your terminal

This command displays a clock on your terminal which updates the time every second. Press Ctrl-C to exit.

A couple of variants:

A little bit bigger text:

watch -t -n1 "date +%T|figlet -f big"

You can try other figlet fonts, too.

Big sideways characters:

watch -n 1 -t '/usr/games/banner -w 30 $(date +%M:%S)'

This requires a particular version of banner and a 40-line terminal or you can adjust the width ("30" here).

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sudo pmset -a hibernatemode 1
2009-06-20 22:52:10
User: thebillywayne
Functions: sudo
-1
Up
Down
Mac OS X (laptops ??) only : control hibernation state more easily from Terminal.app

sudo pmset -a hibernatemode 1 sets hiberate on.

sudo pmset -a hibernatemode 0 sets hibernate off.

from the pmset man page:

0001 (bit 0) enables hibernation; causes OS X to write memory state to

hibernation image at sleep time. On wake (without bit 1 set) OS X will

resume from the hibernation image. Bit 0 set (without bit 1 set) causes

OS X to write memory state and immediately hibernate at sleep time.

I often change my MacBook's sleep state. So I created a function for bash to make it a little easier.

Usage:

hibernate (on | off)

"hibernate on" will set your laptop to hibernate if the lid is closed.

"hibernate off" will set your laptop to sleep if the lid is closed.

### note : "proper" indentation isn't preserved on the website

function hibernate()

{

case "${1}" in

on)

sudo pmset -a hibernatemode 1

echo Hibernate mode on.

;;

off)

sudo pmset -a hibernatemode 0

echo Hiberate mode off.

;;

*)

echo "I'm sorry Dave, but I can't do that."

;;

esac

}

To make things easier, add the proper line in your /etc/sudoers file so that your user may invoke pmset without a password. Here's how mine looks:

bwayne luna = NOPASSWD: /usr/bin/pmset

Don't forget that you must edit sudoers with `sudo visudo` from Terminal.app, and not by another text editor.

Sorry this is so Mac OS specific.

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