Commands by m_a_xim (1)

  • Wait for an already launched program to stop before starting a new command.

    The '[r]' is to avoid grep from grepping itself. (interchange 'r' by the appropriate letter) Here is an example that I use a lot (as root or halt will not work): while (ps -ef | grep [w]get); do sleep 10; done; sleep 60; halt I add the 'sleep 60' command just in case something went wrong; so that I have time to cancel. Very useful if you are going to bed while downloading something and do not want your computer running all night.


    -2
    while (ps -ef | grep [r]unning_program_name); do sleep 10; done; command_to_execute
    m_a_xim · 2010-01-14 16:26:34 0

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 debian package names corresponding to latex packages used in a document

Rename files in batch

check open ports without netstat or lsof

last.fm rss parser
you can just use one awk script to parse the rss feed. No need to pipe so many awk's and sed's. Its ugly and inefficient.

Hide or show Desktop Icons on MacOS
Hides all Files and Folders on the MacOS Desktop. To show files and folders, type "true" instead of "false". "Finder" at the end is case sensitive, "finder" doesn’t work

sleep until X o'clock
pauses exactly long enough to wake at the top of the hour

list block devices
Shows all block devices in a tree with descruptions of what they are.

Convert a MOV captured from a digital camera to a smaller AVI
Convert those .mov files that your digital camera makes to .avi Adjust the bitrate (-b) to get the appropriate file size. A larger bitrate produces a larger (higher quality) .avi file and smaller bitrate produces a smaller (lower quality) .avi file. Requires ffmpeg (see man page for details) (tested with canon camera MOV files) Other examples: $ffmpeg -i input.mov -sameq -vcodec msmpeg4v2 -acodec pcm_u8 output.avi $ffmpeg -i input.mov -b 1024k -vcodec msmpeg4v2 -acodec pcm_u8 output.avi

Recursively find top 20 largest files (> 1MB) sort human readable format
Search for files and list the 20 largest. $ find . -type f gives us a list of file, recursively, starting from here (.) $ -print0 | xargs -0 du -h separate the names of files with NULL characters, so we're not confused by spaces then xargs run the du command to find their size (in human-readable form -- 64M not 64123456) $ | sort -hr use sort to arrange the list in size order. sort -h knows that 1M is bigger than 9K $ | head -20 finally only select the top twenty out of the list

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"

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: