Given a (long) string, ineterleave a fixed byte value after every existing byte.

Simple task with many solutions, but is there one that's quickest? 

$buf = chr(1) x 1e6;;
$s = time; 
$out = join( chr(0), unpack '(A1)*', $buf ) .chr(0); 
print time() - $s;;
11.3910000324249

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In reply to Interleaving bytes in a string quickly by BrowserUk

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