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How can I detect an open com port?

Posted by rpmorrow (rpmorrow), 22 August 2007

Is there a way to detect which (if any) serial ports are allready open?

Cheers, Rich

Posted by admin (Graham Ellis), 23 August 2007
If you're looking within your current program, then I would use variables to keep track of what you have opened.   If you're looking as to what other programs have devices open, it can be less straightforward; you could use co-operative locks / status files between applications (that'w what I would be tempted to do on platforms that don't have am OS with built in locking).

Posted by rpmorrow (rpmorrow), 24 August 2007
My intention is to make it so that if a com port is allready in use (by any program) when my program starts, it should be closed so my program can open it. I was kinda hoping for it to be as simple as some sort of close all ports command

Posted by cwjolly (cwjolly), 24 August 2007
on unix there is a utility called lsof that can be used to determine if a process has a file or device open.  

Posted by admin (Graham Ellis), 25 August 2007
on 08/24/07 at 21:55:30, cwjolly wrote:
on unix there is a utility called lsof that can be used to determine if a process has a file or device open.  

Good thought - Thanks

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