Instead of a s/// you could use a simple substr() 
substr($_, 321, 1) = "\n"

[download]
substr() is the closest thing to referencing strings by index in perl (esp. thanks to it's lvalueability).
HTH

_________
broquaint

In reply to Re: Insert at regular increments by broquaint
in thread Insert at regular increments by EyeOpener

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