GrandFather,
The problem asked is far more interesting than the real problem actually desired (last 4 chars of a string). I would submit the following as a starting point for the asked problem: 
my $desired = substr($string, index($string, $tail) - 4, 4);

[download]
It has a few obvious flaws but since the desired problem isn't the one asked, I didn't pursue it.

Cheers - L~R

In reply to Re^2: substring problem??? by Limbic~Region
in thread substring problem??? by Anonymous Monk

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