Commands by karel1980

Commands by karel1980 (4)

sorted by

Generat a Random MAC address

Just increase the 1 at the end if you want to generate more than one. (Alternative to "| head -n N" you could use the -b flag of od: -b $[6*N] Show Sample Output
This is sample output - yours may be different.
```
ca:41:5d:28:ad:a2
```
2

od /dev/urandom -w6 -tx1 -An|sed -e 's/ //' -e 's/ /:/g'|head -n 1

karel1980 · 2011-05-16 15:05:34 1
Delete all but the latest 5 files, ignoring directories
This is sample output - yours may be different.
1

ls -lt|grep ^-|awk 'NR>5 { print $8 }'|xargs -r rm

karel1980 · 2009-09-16 07:43:03 0
Merge ( directories [looking for improvement]

Using a GUI file managers you can merge directories (cut and paste). This command roughly does the same (it doesn't ask for confirmation (no problem for me) and it doesn't clean up the empty SRC directories (no problem, trivial). probably does the same: cp -l SRC TARGET; rm -rf SRC
This is sample output - yours may be different.
0

(cd SRC; find . -type d -exec mkdir TARGET/{} ";"; find . -type f -exec mv {} TARGET/{} ";")

karel1980 · 2009-08-17 12:35:48 4
Move all images in a directory into a directory hierarchy based on year, month and day based on exif information

This command would move the file "dir/image.jpg" with a "DateTimeOriginal" of "2005:10:12 16:05:56" to "2005/10/12/image.jpg". This is a literal example from the exiftool man page, very useful for classifying photo's. The possibilities are endless. Show Sample Output
This is sample output - yours may be different.
```
    1 directories scanned
    1 directories created
  222 image files updated
    1 image files unchanged
```
15

exiftool '-Directory<DateTimeOriginal' -d %Y/%m/%d dir

karel1980 · 2009-08-04 11:47:34 6

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands

Check These Out

Get information about libraries currently installed on a system.

This command is very helpful when we need to duplicate a test scenario and first we want to find out the installed libraries together with the version and release numbers and architecture. (look example) Command can be tuned by choosing just the names of libraries we are interested in. For example glibc and gcc.

Play all files in the directory using MPlayer

Skip forward and back using the < and > keys. Display the file title with I.

grep for minus (-) sign

Use flag "--" to stop switch parsing

eavesdrop

Record off the microphone on a remote computer and listen to it live through your speakers locally.

check open ports without netstat or lsof

Display two calendar months side by side

Displays last month, current month, and next month side by side.

Count the number of characters in each line

ping a host until it responds, then play a sound, then exit

Audio acknowledgement for host availability. When running the command from a Linux systems, you can use "festival" or "espeak" instead of "say".

Which processes are listening on a specific port (e.g. port 80)

swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

The wisdom of Cave Johnson

There's been a similar Futurama thing around for a while, which grabs a quote from the /. headers [curl -Ism3 slashdot.org | egrep "^X-(F|B|L)" | cut -d \- -f 2- | fmt -w $(tput cols)]. Same deal, but more likely to stop working when someone forgets to pay the bill on the domain. Until then: Cave Johnson!

Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for:

» all commands
» commands with 3 up-votes (commandlinefu3)
» commands with 10 up-votes (commandlinefu10)
» commands by karel1980