Wes Garland wrote in a message to Roy J. Tellason:

 RJT> Because with *.MSG being stored one message-per-file,  the 
 RJT> software (at least some of it) would look for each and every 
 RJT> number,  starting from 1,  by way of dos filesystem calls,  which 
 RJT> was very slow and inefficient.  Putting them all together with 
 RJT> consecutive low numbers does away with this problem.

 WG> FWIW, that shouldn't happen under max/unix -- I'm pretty sure Scott
 WG> uses FindOpen() to find *.MSG files by wildcard; this in turn gets
 WG> translated into a glob() expression for *.[Mm][Ss][Gg], which gets
 WG> returned from a single diropen() at the OS level (e.g. glob expands
 WG> the wildcards into an array of char stars)

I've heard it said elsewhere that *.msg should be a whole lot less of a
problem for unix-type platforms than it was elsewhere,  though I can't
recall the reason given at the moment.  I know that back when I was
programming this sort of thing under CP/M and early on in DOS,  that was a
sequential search and could take a lot of time.

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