What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again.

Delete that bloated snippets file you've been using and share your personal repository with the world. 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.

Get involved!

You can sign-in using OpenID credentials, or register a traditional username and password.

First-time OpenID users will be automatically assigned a username which can be changed after signing in.

Universal configuration monitoring and system of record for IT.

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:



May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

Top Tags



Psst. Open beta.

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:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Commands using losetup from sorted by
Terminal - Commands using losetup - 3 results
FILE=file_name; CHUNK=$((64*1024*1024)); SIZE=$(stat -c "%s" $FILE); for ((i=0; i < $SIZE; i+=$CHUNK)); do losetup --find --show --offset=$i --sizelimit=$CHUNK $FILE; done
2014-10-03 13:18:19
User: flatcap
Functions: losetup stat

It's common to want to split up large files and the usual method is to use split(1).

If you have a 10GiB file, you'll need 10GiB of free space.

Then the OS has to read 10GiB and write 10GiB (usually on the same filesystem).

This takes AGES.


The command uses a set of loop block devices to create fake chunks, but without making any changes to the file.

This means the file splitting is nearly instantaneous.

The example creates a 1GiB file, then splits it into 16 x 64MiB chunks (/dev/loop0 .. loop15).


Note: This isn't a drop-in replacement for using split. The results are block devices.

tar and zip won't do what you expect when given block devices.


These commands will work:

hexdump /dev/loop4


gzip -9 < /dev/loop6 > part6.gz


cat /dev/loop10 > /media/usb/part10.bin
edrv() { N=${1:-edrv}; truncate -s ${2:-256m} $N.img && L=$(losetup -f) && losetup $L $N.img && cryptsetup luksFormat --batch-mode $L && cryptsetup luksOpen $L $N && mkfs.vfat /dev/mapper/$N -n $N; cryptsetup luksClose $N; echo losetup -d $L to unmount; }
2014-02-24 01:38:21
User: snipertyler
Functions: echo losetup

You need to be root to do this. So check the command before running it.

You enter the same password for

Enter LUKS passphrase:

Verify passphrase:

Enter passphrase for /dev/loopn:


You can then copy the .img file to somewhere else.

Loop it it with losetup -f IMAGENAME.img and then mount it with a file manager (eg nemo) or run mount /dev/loopn /media/mountfolder

Acts similar to a mounted flash drive

losetup /dev/loop0 harddrive.img; kpartx -a -v /dev/loop0; mount /dev/mapper/loop0p1 /mountpoint/