In the event you cannot use any other modules (as seems to be common with questions of this sort), and you want the file name, with extention ... you could use : 
my $file = $full_name;
$file =~ s!.*\\!!g;

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I think this is covered in The Perl Cookbook quite well.
from the frivolous to the serious

In reply to Re: Separating file names from path names by MZSanford
in thread Separating file names from path names by Anonymous Monk

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