Comment 11 for bug 543183

Comment on attachment 451412
revised patch to try system db only on unix

Bob Relyea is the best person to review this patch.

Bob, it'd be bad if an application had to read pkcs11.txt
directly and look for "library=libnsssysinit.so".

This should be done by the NSS initialization functions.
If we have a good error code that NSS initialization functions
can return to indicate a missing pkcs11.txt unambiguously,
an application can simply try initializing NSS with
"sql:/etc/pki/nssdb", and fall back on the home/profile
directory if it gets that error code.