Maybe a bit less ugly?
I changed it from 5000 to 79 so that one can view the result. 
$window=79;
$i=-1;
$str="X" x 723;

substr($str,$i,0)="\n" while (($i+=$window+1) < length($str));

print $str;

[download]
This works by inserting "\n" at every $window+1 position.

In reply to Re: string length problems by Skeeve
in thread string length problems by Anonymous Monk

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