Perl script to check an SSL certificate and warn and/or alarm if the certificate is due to expire.

Differs from other version of check_ssl_cert in that temporary files are not used (as per Nagios documentation). In addition, Date::Calc is not used (no separate Perl plugins required).

It was written without me being aware that check_ssl_cert exists as it is not in the Networking section of Check Plugins.

Requires a working OpenSSL version.