Commands by polaco (6)

  • This is a very simple and lightweight way to play DI.FM stations For a more complete version of the command with proper strings in the menu, try: (couldnt fit in the command field above) zenity --list --width 500 --height 500 --title 'DI.FM' --text 'Pick a Radio' --column 'radio' --column 'url' --print-column 2 $(curl -s http://www.di.fm/ | awk -F '"' '/href="http:.*\.pls.*96k/ {print $2}' | sort | awk -F '/|\.' '{print $(NF-1) " " $0}') | xargs mplayer This command line parses the html returned from http://di.fm and display all radio stations in a nice graphical menu. After the radio is chosen, the url is passed to mplayer so the music can start dependencies: - x11 with gtk environment - zenity: simple app for displaying gtk menus (sudo apt-get install zenity on ubuntu) - mplayer: simple audio player (sudo apt-get install mplayer on ubuntu) Show Sample Output


    16
    zenity --list --width 500 --height 500 --column 'radio' --column 'url' --print-column 2 $(curl -s http://www.di.fm/ | awk -F '"' '/href="http:.*\.pls.*96k/ {print $2}' | sort | awk -F '/|\.' '{print $(NF-1) " " $0}') | xargs mplayer
    polaco · 2010-04-28 23:45:35 17
  • Merge files, joining line by line horizontally. Very useful when you have a lot of files where each line represents an info about an event and you want to join them into a single file where each line has all the info about the same event See the example for a better understanding Show Sample Output


    3
    paste file1 file2 fileN > merged
    polaco · 2010-03-12 16:34:48 7
  • The above code is just an example of printing on the same line, hit Ctrl + C to stop When using echo -ne "something\r", echo will: - print "something" - dont print a new line (-n) - interpret \r as carriage return, going back to the start of the line (-e) Remember to print some white spaces after the output if your command will print lines of different sizes, mainly if one line will be smaller than the previous Edit from reading comments: You can achieve the same effect using printf (more standardized than echo): while true; do printf "%-80s\r" "$(date)"; sleep 1; done


    12
    while true; do echo -ne "$(date)\r"; sleep 1; done
    polaco · 2009-11-17 22:45:37 14
  • This script creates date based backups of the files. It copies the files to the same place the original ones are but with an additional extension that is the timestamp of the copy on the following format: YearMonthDay-HourMinuteSecond Show Sample Output


    6
    backup() { for i in "$@"; do cp -va $i $i.$(date +%Y%m%d-%H%M%S); done }
    polaco · 2009-11-10 20:59:45 22
  • This script will list all the files in the tarballs present on any folder or subfolder of the provided path. The while loop is for echoing the file name of the tarball before listing the files, so the tarball can be identified


    -2
    find <path> -name "*.tgz" -or -name "*.tar.gz" | while read file; do echo "$file: "; tar -tzf $file; done
    polaco · 2009-11-10 20:39:04 38
  • This command will copy a folder tree (keeping the parent folders) through ssh. It will: - compress the data - stream the compressed data through ssh - decompress the data on the local folder This command will take no additional space on the host machine (no need to create compressed tar files, transfer it and then delete it on the host). There is some situations (like mirroring a remote machine) where you simply cant wait for a huge time taking scp command or cant compress the data to a tarball on the host because of file system space limitation, so this command can do the job quite well. This command performs very well mainly when a lot of data is involved in the process. If you copying a low amount of data, use scp instead (easier to type) Show Sample Output


    12
    ssh <host> 'tar -cz /<folder>/<subfolder>' | tar -xvz
    polaco · 2009-11-10 20:06:47 10

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