Commands by PLA (7)

  • Put public IP address in a variable


    2
    ip=$(curl ip.pla1.net)
    PLA · 2016-01-28 19:29:48 16
  • Send a message to Kodi (XBMC)

    Send a text message to an Kodi (XBMC) device. Uses curl to post a JSON request to the Kodi JSON-RPC API.


    0
    curl -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","method":"GUI.ShowNotification","params":{"title":"This is the title of the message","message":"This is the body of the message"},"id":1}' http://i3c.pla.lcl:8080/jsonrpc
    PLA · 2014-08-24 21:49:13 29
  • Determine MythTV Version on a Debian System

    Use this command to determine what version of MythTV you are running on a Debian system. Tested on a Mythbuntu installation. Show Sample Output


    -2
    apt-cache policy mythtv
    PLA · 2011-08-05 17:34:41 3
  • Using wget to receive an XML atom feed of your Gmail inbox

    I use this command in my Conky script to display the number of messages in my Gmail inbox and to list the from: and subject: fields. Show Sample Output


    -3
    wget -O - 'https://USERNAMEHERE:PASSWORDHERE@mail.google.com/mail/feed/atom' --no-check-certificate
    PLA · 2010-09-26 14:47:13 6
  • ffmpeg command that transcodes a MythTV recording for Google Nexus One mobile phone

    This command will transcode a MythTV recording. The target device is a Google Nexus One mobile phone. My recordings are from a HDHomerun with Over The Air content. Plays back nicely on the N1.


    2
    ffmpeg -i /var/lib/mythtv/pretty/Chuck20100208800PMChuckVersustheMask.mpg -s 800x480 -vcodec mpeg4 -acodec libfaac -ac 2 -ar 16000 -r 13 -ab 32000 -aspect 16:9 Chuck20100208800PMChuckVersustheMask.mp4
    PLA · 2010-02-12 12:11:02 7
  • Extract audio from Mythtv recording to Rockbox iPod using ffmpeg

    There are some pretty good live performances on late night TV. With Mythtv I record David Letterman, Jimmy Fallon, and Conan nightly all in HD from over the air broadcasts. If I find a live performance I like I copy it to my Rockboxed iPod using this command. The Rockbox firmware knows how to downmix 5.1 audio. The command above extracts the audio from the video starting at 58 minutes and 15 seconds. It ends at the end of the file since this was the last performance of the recording. The command creates an ac3 file. I copy the ac3 file to my Rockbox iPod and rock on.


    3
    ffmpeg -ss 0:58:15 -i DavidLettermanBlackCrowes.mpg -acodec copy DavidLettermanBlackCrowes.ac3
    PLA · 2009-09-14 00:08:36 3
  • Use xdg-open to avoid hard coding browser commands

    I rarely use the system menu to start applications. I use keyboard shortcuts instead. Keyboard shortcuts are convenient time savers. To configure the shortcuts I use gconf-editor or CompizConfig Settings Manager (if I have Compiz turned on). Lately I've been using Chromium as my browser. Since Chromium is under heavy development it occasionally becomes unusable and I have to switch back to Firefox. I was hard-coding the browser command in my keyboard shortcuts. This became problematic with frequent browser hopping. I now use the xdg-open command when defining my keyboard shortcuts. xdg-open opens a file or URL in the user's preferred application. In the metacity keybinging_commands I have xdg-open http://gmail.com where I used to have firefox http://gmail.com. Now when switching browsers I don't have to update each keyboard binding command I just change my default browser in Ubuntu by clicking through the menu: System / Preferences / Preferred Applications / Web Browser. xdg-open is more convenient for this browser hopper.


    8
    xdg-open http://gmail.com
    PLA · 2009-07-11 11:48:32 10

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Transfer SSH public key to another machine in one step
This command sequence allows simple setup of (gasp!) password-less SSH logins. Be careful, as if you already have an SSH keypair in your ~/.ssh directory on the local machine, there is a possibility ssh-keygen may overwrite them. ssh-copy-id copies the public key to the remote host and appends it to the remote account's ~/.ssh/authorized_keys file. When trying ssh, if you used no passphrase for your key, the remote shell appears soon after invoking ssh user@host.

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Read aloud a text file in Mac OS X

Get Hardware UUID in Mac OS X
Formats the output from `ioreg` into XML, then parses the XML with `xmllint`'s xpath feature.

Tracklist reaplace backspace to '-'
Requires perl 5.14 or greater

Download all PDFs from an authenificated website
Replace *** with the appropiate values

Multi-thread any command
For instance: $ find . -type f -name '*.wav' -print0 |xargs -0 -P 3 -n 1 flac -V8 will encode all .wav files into FLAC in parallel. Explanation of xargs flags: -P [max-procs]: Max number of invocations to run at once. Set to 0 to run all at once [potentially dangerous re: excessive RAM usage]. -n [max-args]: Max number of arguments from the list to send to each invocation. -0: Stdin is a null-terminated list. I use xargs to build parallel-processing frameworks into my scripts like the one here: http://pastebin.com/1GvcifYa

disable caps lock
a quick one-line way to disable caps lock while running X.

Image to color palette generator
Extract a color palette from a image useful for designers. Example usage: $extract-palette myawesomeimage.jpg 4 Where the first argument is the image you want to extract a palette from. The second argument is the number of colors you want. It may be the case where you want to change the search space. In that case, change the -resize argument to a bigger or smaller result. See the ImageMagick documentation for the -resize argument.

Setting reserved blocks percentage to 1%
According to tune2fs manual, reserved blocks are designed to keep your system from failing when you run out of space. Its reserves space for privileged processes such as daemons (like syslogd, for ex.) and other root level processes; also the reserved space can prevent the filesystem from fragmenting as it fills up. By default this is 5% regardless of the size of the partition. http://www.ducea.com/2008/03/04/ext3-reserved-blocks-percentage/

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