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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,…):
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if you use disk-based swap then it can defeat the purpose of this function.
Renames files in a directory to incremental numbers, following alphabetic order. The command does not maintain extensions.
rename is a great command, but can't get it to work on mac.
Prepends all directory items with "prependtext"
all files in the directory get moved, in doing so the new name of the file is the original name with out spaces (using translate command)
This heavy one liner gets all the files in the "/music/dir/" directory and filters for non 44.1 mp3 files. After doing this it passes the names to sox in-order to re-sample those files. The original files are left just in case.
Thanks th John_W for suggesting the fix allowing ~/ to be used when saving a directory.
Type in a url, it will show a preview of what the file will look like when saved, then asks if you want to save the preview and where you want to save it. Great for grabbing the latest commandlinefu commands without a full web browser or even a GUI. Requires: w3m
I wrote this script to speed up Nginx configs. This (long) one liner can be run via BASH. You will see that we set a variable in bash called 'foo' and the streamline editor (sed) finds 'bar' in 'foo.conf' next it writes that output to a temp file (foo.temp) and removes the first 5 lines (that aren't needed in this case) & lastly it moves (overwrites) foo.temp to foo.conf
We normally get tasks in which one has to sort a data file according to some column. For a single file say foo, we would use
sort -k 3 foo >tmp && tmp foo
The for loop is useful when we have to do it on a number of files.
Thanks to flatcap for optimizing this command.
This command takes advantage of the ext4 filesystem's resistance to fragmentation.
By using this command, files that were previously fragmented will be copied / deleted / pasted essentially giving the filesystem another chance at saving the file contiguously. ( unlike FAT / NTFS, the *nix filesystem always try to save a file without fragmenting it )
My command only effects the home directory and only those files with your R/W (read / write ) permissions.
There are two issues with this command:
1. it really won't help, it works, but linux doesn't suffer much (if any ) fragmentation and even fragmented files have fast I/O
2. it doesn't discriminate between fragmented and non-fragmented files, so a large ~/ directory with no fragments will take almost as long as an equally sized fragmented ~/ directory
The benefits i managed to work into the command:
1. it only defragments files under 16mb, because a large file with fragments isn't as noticeable as a small file that's fragmented, and copy/ delete/ paste of large files would take too long
2. it gives a nice countdown in the terminal so you know how far how much progress is being made and just like other defragmenters you can stop at any time ( use ctrl+c )
3. fast! i can defrag my ~/ directory in 11 seconds thanks to the ramdrive powering the command's temporary storage
1. its only an experiment, safe ( i've used it several times for testing ), but probably not very effective ( unless you somehow have a fragmentation problem on linux ). might be a placebo for recent windows converts looking for a defrag utility on linux and won't accept no for an answer
2. it's my first commandlinefu command
Checks if a web page has changed. Put it into cron to check periodically.
Change http://www.page.de/test.html and email@example.com for your needs.
In a folder with many files and folders, you want to move all files where the date is >= the file olderFilesNameToMove and
Simple bash/ksh/sh command to rename all files from lower to upper case. If you want to do other stuff you can change the tr command to a sed or awk... and/or change mv to cp....
This renames a pattern matched bunch of files by their last modified time.
rename by timestamp
rename by time created
rename by time modified
Just a quick hack to give reasonable filenames to TrueType and OpenType fonts.
I'd accumulated a big bunch of bizarrely and inconsistently named font files in my ~/.fonts directory. I wanted to copy some, but not all, of them over to my new machine, but I had no idea what many of them were. This script renames .ttf files based on the name embedded inside the font. It will also work for .otf files, but make sure you change the mv part so it gives them the proper extension.
REQUIREMENTS: Bash (for extended pattern globbing), showttf (Debian has it in the fontforge-extras package), GNU grep (for context), and rev (because it's hilarious).
BUGS: Well, like I said, this is a quick hack. It grew piece by piece on the command line. I only needed to do this once and spent hardly any time on it, so it's a bit goofy. For example, I find 'rev | cut -f1 | rev' pleasantly amusing --- it seems so clearly wrong, and yet it works to print the last argument. I think flexibility in expressiveness like this is part of the beauty of Unix shell scripting. One-off tasks can be be written quickly, built-up as a person is "thinking aloud" at the command line. That's why Unix is such a huge boost to productivity: it allows each person to think their own way instead of enforcing some "right way".
On a tangent: One of the things I wish commandlinefu would show is the command line HISTORY of the person as they developed the script. I think it's that conversation between programmer and computer, as the pipeline is built piece-by-piece, that is the more valuable lesson than any canned script.
Need to have rc iso pre-downloaded before running command.
Some commands (such as sed and perl) have options to support in-place editing of files, but many commands do not. This shell function enables any command to change files in place. See the sample output for many examples.
The function uses plain sh syntax and works with any POSIX shell or derivative, including zsh and bash.
This got a bit complicated, because I had to introduce an additional dot at the end that has to be removed again later.