This is Perl module Net::SSL::ExpireDate.
Net::SSL::ExpireDate installation is straightforward. If your CPAN shell is set up, you should just be able to do
% cpan Net::SSL::ExpireDate
Download it, unpack it, then build it as per the usual:
% perl Makefile.PL
% make && make test
Then install it:
% make install
Net::SSL::ExpireDate documentation is available as in POD. So you can do:
% perldoc Net::SSL::ExpireDate
to read the documentation online with your favorite pager.
Copyright HIROSE Masaaki
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.