number being returned for mktime and timegm calls. Choose 48 because
that works well. This does reduce the dynamic range of tm_year from
about 2 billion years down to "only" about 9 million years. Please
contact me if this restriction poses a problem.
Due to the complexity of the code, I admit that I didn't trace down
what, exactly, was overflowing with longer bits. This fixes software
that we run on the embedded systems we have.