This may not work as portably as you want, but if it does, it's definately the obscure way: 

use strict;
use warnings;
require 5.8.0;
my $string = "......bytes....";
local $/=\1;
open FH, "<", \$string or die $!;
while (my $byte = <FH> ) {
    #do your stuff with $byte
}
close FH;

[download]

It relies on the fact that setting the $/ input separator to a numeric value reads in that number of bytes. It also relies on the Perl 5.8.0 or later "In-memory file" open, where you can essentially open a scalar instead of a file. You then read the scalar in byte by byte.

I wouldn't recommend it for much, but it's an interesting exercise.

Update: Thanks Anonymous Monk for catching the glitch. I knew I was forgetting something. My original code read: local $/=1;. I've now corrected my snippet.

Update 2: After some testing and re-reading the appropriate documentation, it appears that this method will work, as long as you're using it on Perl 5.8.0 or later.


Dave


"If I had my life to live over again, I'd be a plumber." -- Albert Einstein

In reply to Re: How do I safely, portably extract one or more bytes from a string? by davido
in thread How do I safely, portably extract one or more bytes from a string? by Anonymous Monk

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