William McBrine wrote in a message to Bo Simonsen:

 WM> One small change -- better make this_rec an unsigned long:



Nice to see you jumping in here...

Sometimes I wish that _unsigned_ had been the default rather than signed! 
This one seems to pop up with different software fairly regularly,  and way
too many programmers just seem to figure that they don't need to bother
with that extra little bit of typing "because the number won't get big
enough to make a difference"!

One program I use a *lot* here on this (dos/dv) box is InspectA.  Works
fine for me for the most part.  But when I ran the OS/2 version and had a
5G+ HPFS partition to play with,  the free space was incorrect,  showing up
as a modulo something signed number.   I got to where I couldn't move files
because of "insufficient space" but they moved fine manually, 
until the number wrapped around again...

Heard of lots of other folks getting bit by this one,  too.

---