use some descriptions from Lutz' redundant manual page

=over 4

=item SSLEAY_VERSION

The text variant of the version number and the release date.  For example,

"OpenSSL 0.9.5a 1 Apr 2000".

=item SSLEAY_CFLAGS

The flags given to the C compiler when compiling OpenSSL are returned in a

string.

The compiler flags set for the compilation process in the form

"compiler: ..."  if available or "compiler: information not available"

otherwise.

=item SSLEAY_BUILT_ON

The date of the build process in the form "built on: ..." if available

or "built on: date not available" otherwise.

=item SSLEAY_PLATFORM

The platform name used when OpenSSL was configured is returned.

=back

The "Configure" target of the library build in the form "platform: ..."

if available or "platform: information not available" otherwise.

If the data request isn't available, a text saying that the information is

not available is returned.

=back

For an unknown B<t>, the text "not available" is returned.