Commands by ppq (2)

  • Remove specific versions of old kernels (Ubuntu/Debian)

    If, for example, you want to remove all kernels and headers but the last three versions, you can't use one of that magic all-in-one "remove old stuff" commands. With this simple but elegant command you can remove a range of versions, or a list of versions with e.g. {14,16,20}. Show Sample Output


    1
    apt purge linux*{14..18}*
    ppq · 2016-04-20 07:44:55 14
  • Burn a simple DVD-Video without menu using any given video file

    This is the fastest way to burn a DVD-Video from the command line. Dependencies: libav-tools dvdauthor growisofs The first command: avconv -i input.avi -target pal-dvd dvd.mpg converts any given video file avconv can handle into MPEG2-PS (6 Mbit/s) with AC3 audio (448 kbit/s). If your distribution is not up to date, just use ffmpeg - the syntax is the same. Hint: If you want to create an NTSC DVD, type ntsc-dvd instead ;-) The second command: echo PAL > ~/.config/video_format sets PAL as your default video format. This is a workaround for an old dvdauthor bug. If you want NTSC, guess what? Type NTSC instead! The third command: dvdauthor -o dvd/ -t dvd.mpg creates .VOB files and adds them to the dvd/ folder. You don't have to create this folder yourself. You can add as many titles as you like, just keep in mind that there's a maximum of 4482 MiB (4.37 GiB) for normal DVDs. The fourth command: dvdauthor -o dvd/ -T finishes the DVD-Video. Now you can burn your DVD using growisofs: growisofs -Z /dev/dvd -dvd-video dvd/ Sources: manpages http://tuxicity.wordpress.com/2006/12/01/avi-to-dvd-with-ffmpeg-and-dvdauthor/


    0
    avconv -i input.avi -target pal-dvd dvd.mpg && echo PAL > ~/.config/video_format && dvdauthor -o dvd/ -t dvd.mpg && dvdauthor -o dvd/ -T && growisofs -Z /dev/dvd -dvd-video dvd/
    ppq · 2012-09-09 20:56:54 5

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Open a manpage in the default (graphical) web browser
An easy alias for opening a manpage, nicely HTML formatted, in your set internet browser. If you get a "command exited with status 3" error you need to install groff.

To create files with specific permission:

Dump audio from video without re-encoding.
This removes the video and subsequent file size and directly copies the audio.

Clean all .pyc files from current project. It cleans all the files recursively.

check for write/read permissions
su www-apache/ftp user and then check readable: find ~/ -type d \( -wholename '/dev/*' -o -wholename '/sys/*' -o -wholename '/proc/*' \) -prune -o -exec test -r {} \; -exec echo {} readable \; 2>/dev/null check writable: find ~/ -type d \( -wholename '/dev/*' -o -wholename '/sys/*' -o -wholename '/proc/*' \) -prune -o -exec test -w {} \; -exec echo {} writable \; 2>/dev/null

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"

tar exclude files or directories
If you want to exclude only one file or directory you should use as --exclude=file_or_directory

Terrorist threat level text

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" }

Count items in JSON array
Pipe any JSON to jq, then count with the appropiate expression and use the | length on the array

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