Converting Null

Simple shell script fix this week – convert all newlines to null characters.

Since most Linux shells have a major problem with doing this in a sensible way, the following (on my box called simply ’0′) takes any input (either from files or via a pipe) and converts the characters.

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#!/usr/bin/perl
# From: http://hash-bang.net/2009/04/converting-nullconverting-null/
# Author: Matt Carter <m@ttcarter.com>
while (<>) {
	s/\n/\x00/g;
	print;
}

So now commands like:

find -type f | 0 | xargs -0 | mplayer

work perfectly (in the above case to play all files in directories recursively.

You may well ask why I don’t use the simple ‘-print0′ argument for the find program – because it doesn’t work when using later pipes.

For example if i wanted to sort the above, ‘sort’ would see the null symbol as a regular character.

So ’0′ works nicely in this case:

find -type f | 0 | sort | xargs -0 | mplayer

Or even:

find -type f | 0 | shuffle | xargs -0 | mplayer

To play all files recursively, in random order. See the article on shuffle for the source code of that filter.