All commands (14,187)

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

Merge PDFs with Ghostscript wrapped in a function
This is an expansion on a previous entry, which I've wrapped in a function and placed in my profile. The "$@" is a positional parameter, much like "$*", but the parameters are passed on intact, without interpretation or expansion; so you can simply call the function like this: mergepdf * This will output a merged PDF of all PDFs in the current directory. Alternatively, you can simply list them like so: mergepdf 00.pdf 01.pdf 02.pdf ... N.B. Passing a wildcard will merge all PDFs in the current directory in name order, e.g. 00.pdf 01.pdf aa.pdf ab.pdf

recursive search and replace old with new string, inside files
This command find all files in the current dir and subdirs, and replace all occurances of "oldstring" in every file with "newstring".

Convert CSV to JSON with miller
Using the csv tool `miller` you can transform a csv file into a json array of objects, where the properties are the values of the csv header line and the values are the values of the subsequent lines.

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"

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"

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"

rename files according to date created
The command renames all files in a certain directory. Renaming them to their date of creation using EXIF. If you're working with JPG that contains EXIF data (ie. from digital camera), then you can use following to get the creation date instead of stat. * Since not every file has exif data, we want to check that dst is valid before doing the rest of commands. * The output from exif has a space, which is a PITA for filenames. Use sed to replace with '-'. * Note that I use 'echo' before the mv to test out my scripts. When you're confident that it's doing the right thing, then you can remove the 'echo'... you don't want to end up like the guy that got all the files blown away. Credits: http://stackoverflow.com/questions/4710753/rename-files-according-to-date-created

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Monitor progress of a command
Pipe viewer is a terminal-based tool for monitoring the progress of data through a pipeline. It can be inserted into any normal pipeline between two processes to give a visual indication of how quickly data is passing through, how long it has taken, how near to completion it is, and an estimate of how long it will be until completion. Source: http://www.catonmat.net/blog/unix-utilities-pipe-viewer/


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: