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.
If you have a new feature suggestion or find a bug, please get in touch via http://commandlinefu.uservoice.com/
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.
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.
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:
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:
gzip -9 < /dev/loop6 > part6.gz
cat /dev/loop10 > /media/usb/part10.bin
You need to be root to do this. So check the command before running it.
You enter the same password for
Enter LUKS 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