Re: Net::Netmask not working with scalar variable

[aquarium]

it's a good idea to open a file for read only, if you only ever intend to only read the file, otherwise it gets opened automatically read+write.
can't test your code at moment but generally when constructing funky strings, especially that $fk is input to a module/function, i'd recommend forming it like so

my $fk = "$ff" . ':255.255.255.0';

to make sure perl doesn't think that $ff: (for instance) is an entry into the symbol table instead of what you intend.
so i always double quote variables separately, and attach other bits of strings in single quotes.

[Anonymous Monk]

open is read only when mode is omitted. The 3 argument form of open is considered better practice:

open(my $fh, '<', "input.txt") or die $!

There is no reason to place a variable in double quotes unless you're interpolating it into a string, so the original poster's code was perfectly fine. To affect the symbol table you'd place 2 colons between barewords; like when you use a module or declare a package.

[sagarkha]

I tried using my $fk = "$ff" . ':255.255.255.0';. I also tried using chomp; But no help in both the cases. I know my regex will matches more than just the Ip addresses like 2223.9991.55654.11111, but i damn sure it will match each and every IP address on the planet. And it is doing it correctly since i am getting the correct IP in $ff. Now, for more troubleshooting i tried printing $ff & $fk and i got the below results, i am not sure what is wrong here

print "$ff\n";
print "$fk\n";
$block4 = Net::Netmask->new2($fk);

Results:

10.6.10.5
:255.255.255.0
Can't call method "size" on an undefined value at save.txt line 55, <F
+> line 23.