Commands by pamirian (5)

  • dname is a directory named something like 20090803 for Aug 3, 2009. lastbackup is a soft link to the last backup made - say 20090802. $folder is the folder being backed up. Because this uses hard linking, files that already exist and haven't changed take up almost no space yet each date directory has a kind of "snapshot" of that day's files. Naturally, lastbackup needs to be updated after this operation. I must say that I can't take credit for this gem; I picked it up from somewhere on the net so long ago I don't remember where from anymore. Ah, well... Systems that are only somewhat slicker than this costs hundreds or even thousands of dollars - but we're HACKERS! We don't need no steenkin' commercial software... :)


    6
    rsync -a --delete --link-dest=../lastbackup $folder $dname/
    pamirian · 2009-08-04 07:08:54 8
  • This requires the command-line print extension (see #2861 for more details). I use it to make up complex images with formatted text using CSS and whatnot. It's a lot slicker than imagemagick for certain things. Now imagine using a local webserver with PHP and a database to generate the images. Oh, the possibilities...


    9
    touch $2;firefox -print $1 -printmode PNG -printfile $2
    pamirian · 2009-08-04 06:55:25 5
  • This uses the "command-line print" plugin for Firefox (http://torisugari.googlepages.com/commandlineprint2). This same plugin can also produce PNGs. On *nix, the file must exist; therefore the touch bit in front. Also, firefox seems to ignore saved user preferences when "printing" this way (margins, header, footer, etc.), so I had to tweak my ~/.mozilla/firefox/xxxxxxxx.default/prefs.js file by hand. Yup, that's *prefs.js* not user.js - apparently, firefox ignores my user.js file too...


    5
    touch $2;firefox -print $1 -printmode PDF -printfile $2
    pamirian · 2009-08-04 06:40:55 2
  • This is an extract from a larger script which formats the video for DVD. The videos I use have no audio track so I need to add one. Tweak as you like...


    6
    cat frame/*.mpeg | ffmpeg -i $ID.mp3 -i - -f dvd -y track/$ID.mpg 2>/dev/null
    pamirian · 2009-08-04 06:31:50 4
  • This is an extract from a larger script which makes up slideshow videos from images. $seconds is the number of seconds the video will last, and $num is a loop counter which numbers the videos for concat into a longer video later, so they will be in order. The dev/null bit on the end cuts ffmpeg's verbosity.


    4
    ffmpeg -loop_input -f image2 -r 30000/1001 -t $seconds -i frame/$num.ppm -y frame/%02d.mpeg 2>/dev/null
    pamirian · 2009-08-04 06:25:47 3

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

Set a Reminder for yourself via the notification system
This will be seen through your system's visual notification system, notify-osd, notification-daemon, etc. --- sleep accepts s,m,h,d and floats (date; sleep .25m; date) --- notify-send (-t is in milliseconds && -u low / normal / critical) man notify-send for more information --- notification-daemon can use b/i/u/a HTML

Sort files in folders alphabetically
Creates one letter folders in the current directory and moves files with corresponding initial in the folder.

echo unicode characters

Merge *.pdf files
Merge all pdf files in the directory into one pdf file (the out.pdf file)

Redefine the cd command's behavior
Often, the very next command after the cd command is 'ls', so why not combine them?. Tested on a Red Hat derivative and Mac OS X Leopard Update: changed ${1:-$HOME} to "${@:-$HOME}" to accomodate directories with spaces in the names

Adding Prefix to File name
Good old bracket expansion :-) For large numbers of files, "rename" will spare you the for-loop, or the find/exec...

Continuously show wifi signal strength on a mac
The closer to zero the better.Credit to TheSeb on macrumors: http://forums.macrumors.com/showthread.php?t=1289884

Netcat Relay
This is an example of using 3 hosts, in a netcat relay. first host connects to middle host 1 -> 2 Second hosts redirects to target host 1 -> 2 -> 3 I hope this makes sense.

Find the package that installed a command

Print today's date in ISO format without calling an external command (bash 4)


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: