I need to write a subnet mask calculator with perl. The extension Net::IP is really powerful.

Well, you could use that module. First thing to do is read its documentation, and off you go. Come back with some code to discuss.

Alternatively I just happen to have a calculator in my toolbox for calculating network, netmask and broadcast out of an IPv4 address in CIDR notation which could be worth being studied by you: 

#!/usr/bin/perl
# file cidr
$m=pack B32,pop=~'/'x$';
printf"$` network %vd broadcast %vd netmask %vd\n",($z=eval$`)&$m,$z|~
+$m,$m;
__END__
Example:
cidr 209.197.123.153/27
209.197.123.153 network 209.197.123.128 broadcast 209.197.123.159 netm
+ask 255.255.255.224

[download]
Consult the perl documentation for its various operators, perl special variables and internal functions.

In reply to Re: Net IP by shmem
in thread Net IP by lddzjwwy

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