As this shows, $+ is the position of the match, not the value of the match. You need to use parentheses to indicate what you want to preserve, with $1 indicating the value of the first match. So your code should look like: 
if ($frameDesc =~ /(\d+)$/ ) {
   print FH "FTP $1\n";
} else {
   print FH "FTP 0\n";
}

[download]
Or, if you were interested in Perl Golf, you might try 
my $value = ($frameDesc =~ /(\d+)$/ ) ? $1 : 0;
print FH "FTP $value\n";

[download]

If you had two sets of parentheses in your regex and you wanted to manipulate the second value, you'd specify $2, etc.

Warning: the code is untested.

In reply to Re: where is /\d+$/ result?? by apl
in thread where is /\d+$/ result?? by rightfield

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