Moin Darin,

13.12.96 21:15, you wrote a message to All :

 DM> Is there anywhere I can pick up a reference on COM.SYS?  

See "Control Program Guide and Reference".

 DM> SIO.SYS is handy - it comes with one.  I'm not sure if COM.SYS
 DM> supports all the IOCtl commands, particularily the extended bit
 DM> rate commands.  

They are the same for both drivers.  IMHO SIO allows you to select bitrates
at a finer granularity.

 DM> If COM.SYS doesn't support some, does anyone know which ones, and
 DM> how, at run-time, I can tell?

Try.  It would be best to stick to documented IOCtls (Control Program Guide
and Reference), you could be using COM, SIO, cFos, some Multiport-Card with
it's own drivers, shared COM-Ports from a different machine on the net, ...

C-x C-s
    Vitus [Team OS/2 Germany #835]

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