$ for i in `seq 1 256`; do echo -n '0123456789ABCDEF' >>file; done
$ for i in `seq 1 256`; do echo "This won't work" >>file; done
$

##</code><code>##

1032547698BADCFE1032547698BADCFE1032547698BADCFE...
khTsiw not'w ro
khTsiw not'w ro
khTsiw not'w ro
...

##</code><code>##

syswrite ( $out_file, $mem_file );