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From: hitt@Neon.Stanford.EDU (Daniel Hitt)
Newsgroups: comp.sys.next
Subject: Re: determining which process owns the serial port
Keywords: serial port, process, ownership
Message-ID: <1990Dec6.063338.402@Neon.Stanford.EDU>
Date: 6 Dec 90 06:33:38 GMT
References: <1990Nov30.185944.12618@Neon.Stanford.EDU> <1990Dec5.130712.18403@thunder.mcrcim.mcgill.edu>
Organization: Computer Science Department, Stanford University
Lines: 19

In article <1990Dec5.130712.18403@thunder.mcrcim.mcgill.edu> mouse@thunder.mcrcim.mcgill.edu (der Mouse) writes:
>
>It's not clear what you mean here.  In what sense can a process "own"
>the serial port?

When you want to use MIDI, for example, you must ``own'' the port.
For example, you could open a couple of terminal windows and use
/NextDeveloper/Examples/MidiDriver/playmidifile to start playing
a midifile, then immediately go to the other window and try to
execute the same program.  It will say ``port in use, become
owner first'' or something similar.

(In fact, if you dig through the documentation, you see that
to play through midi you must own a port---this may be a software
port, but still there's a question of how to determine who owns it.
I'd like to know how to do this determination, from software,
and probably there's some table somewhere which records the necessary info.)

dan