bsdbox

netcalc update: it's 2019 after all

<2019-09-26>

After receiving a request from Martin on the misc@ mailing list to make IPv6 the default version for netcalc, I decided to implement my original idea to dynamically detect which version IP address the user specifies so that no switch is necessary. It was a trivial change but definitely an improvement; and, like Martin remarked, "it's 2019 after all." Despite the fact that IPv4 still traffics most of the Internet with approximately 75% coverage, any encouragement to implement its successor should be the default position.

I am a little surprised that IPv6 wasn't the default taught at university as late as November 2018. In any case, it is no longer necessary to use the -6 switch to specify IPv6 in netcalc:

$ netcalc dfa2:984b:2b37:b4a5:594b:fcbd:66be:4faf/111

Address        : dfa2:984b:2b37:b4a5:594b:fcbd:66be:4faf
CIDR notation  : dfa2:984b:2b37:b4a5:594b:fcbd:66be::/111
Start address  : dfa2:984b:2b37:b4a5:594b:fcbd:66be::
End address    : dfa2:984b:2b37:b4a5:594b:fcbd:66bf:ffff
Block size:    : 131,072 contiguous usable hosts

And a switch still isn't needed for IPv4 either:

$ netcalc 40.33.200.1/27

Address           :   40.33.200.1
CIDR notation     :   40.33.200.0/27
Address range     :   40.33.200.1 —— 40.33.200.30
Broadcast address :   40.33.200.31
Subnet mask       :   255.255.255.224 [0xffffffe0]
Address block     :   30 contiguous hosts

Magic! The updated version is available on the projects page. Alternatively, you can clone the Fossil repository.

Tags: code c
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