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 4
  • 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 1
  • 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 0
  • 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 0
  • 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 1

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Touch a file using a timestamp embedded in the file name.
tstouch takes two arguments: a filename containing a timestamp, and an extended regular expression with the parenthesized section matching a timestamp of the form YYYYMMDDhhmm or YYYYMMDDhhmm.ss. It then touches the file with that timestamp.

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"

Edit a script that's somewhere in your path.
Often I need to edit a bash or perl script I've written. I know it's in my path but I don't feel like typing the whole path (or I don't remember the path).

Download a numbered sequence of files

list files recursively by size

check open ports without netstat or lsof

get diskusage of files modified during the last n days
get diskusage of files (in this case logfiles in /var/log) modified during the last n days: $ sudo find /var/log/ -mtime -n -type f | xargs du -ch n -> last modified n*24 hours ago Numeric arguments can be specified as +n for greater than n, -n for less than n, n for exactly n. => so 7*24 hours (about 7 days) is -7 $ sudo find /var/log/ -mtime -7 -type f | xargs du -ch | tail -n1

See system users

split a multi-page PDF into separate files
Simple alternative to the previous submitted one

Rename files in batch


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