Commands by mohan43u (13)

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Avoid killing the X server with CTRL+C on the tty it was started from

floating point operations in shell scripts
using bc is for sissies. dc is much better :-D Polish notation will rule the world...

Remove audio stream from a media file
This syntax also works for ffmpeg as avconv is a fork of ffmpeg.

Faster find and move using the find and xargs commands. Almost as fast as locate.
Only tested on Linux Ubunty Hardy. Works when file names have spaces. The "-maxdepth 2" limits the find search to the current directory and the next one deeper in this example. This was faster on my system because find was searching every directory before the current directory without the -maxdepth option. Almost as fast as locate when used as above. Must use double quotes around pattern to handle spaces in file names. -print0 is used in combination with xargs -0. Those are zeros not "O"s. For xargs, -I is used to replace the following "{}" with the incoming file-list items from find. Echo just prints to the command line what is happening with mv. mv needs "{}" again so it knows what you are moving from. Then end with the move destination. Some other versions may only require one "{}" in the move command and not after the -I, however this is what worked for me on Ubuntu 8.04. Some like to use -type f in the find command to limit the type.

output the contents of a file removing any empty lines including lines which contain only spaces or tabs.

return external ip
Return IP information about your external ip address with JSON format

Rescan partitions on a SCSI device
Used this after cloning a disk with dd to make the newly written partitions show up in /dev/

cycle through everything sox knows how to read, playing only the first three seconds
I wasted two hours reading the sox documentation and searching on the web for the format of some obscure fscking sound sample, and then finally came up with this. This plays only the first three seconds of your unknown formatted sound file using every one of sox's built-in filetypes. If you don't get an exact match, you may get close. . I could not fit every single type in and keep it under 127 characters, so you will have to replace "..." with the full list obtainable by `$ sox --help` (or try `Show sample output`) . note: /usr/bin/play should be linked to sox on most systems.

Prints total line count contribution per user for an SVN repository
make usable on OSX with filenames containing spaces. note: will still break if filenames contain newlines... possible, but who does that?!

Update grub menu.lst
Remove all commented lines Remove all blank lines Show the menu Up the delay so you have enough time to select a kernel Remove the quiet so you can watch the entire boot Add a rootdelay for san attached storage booting


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