Commands by smoky (1)

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Every Nth line position # (SED)
sed extract every nth line. Generic is: $ sed -n 'STARTPOSITION,${p;n;*LINE}' foo where n;*LINE = how many lines. thus p;n;n; is "for every 3 lines" and p;n;n;n;n; is "for every 5 lines"

Play awesome rythmic noise using aplay
Try modifying the numbers in the "(i*(i>>8|i>>9)&46&i>>8))^(i&i>>13|i>>6)" part. Crudely stolen from http://www.xkcdb.com/9067

Line Separator That is Width of Terminal
Creates a line seperator that will be the width of your window.

list files recursively by size

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

a function to find the fastest DNS server
http://public-dns.info gives a list of online dns servers. you need to change the country in url (br in this url) with your country code. this command need some time to ping all IP in list.

Averaging columns of numbers
This example calculates the averages of column one and column two of "file.dat". It can be easily modified if other columns are to be averaged.

Set gnome wallpaper to a random jpg from the specified directory
Every time this is run it will change your background picture. For added fun Add some DBUS magic: . $HOME/.dbus/session-bus/`cat /var/lib/dbus/machine-id`-0 export DBUS_SESSION_BUS_ADDRESS and a crontab entry: */5 * * * * above_command_in_script.sh >/dev/null 2>/dev/null now wallpaper changes every 5 mins

list files recursively by size

Another way to calculate sum size of all files matching a pattern
Here the pattern is '*.jar', you could pass in any pattern. Another, maybe nicer way to do this is http://www.commandlinefu.com/commands/view/1921/summarise-the-size-of-all-files-matching-a-simple-regex You could replace sed with tr


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