Bug 33916 - Incorrect working of UnixSignal when calling Console.Beep
Summary: Incorrect working of UnixSignal when calling Console.Beep
Status: NEW
Alias: None
Product: Class Libraries
Classification: Mono
Component: Mono.POSIX ()
Version: 4.0.0
Hardware: PC Linux
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2015-09-14 02:09 UTC by BogdanovKirill
Modified: 2015-09-14 02:09 UTC (History)
1 user (show)

Is this bug a regression?: ---
Last known good build:

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Description BogdanovKirill 2015-09-14 02:09:46 UTC
The problem is that UnixSignal doesn't work at all if program sometimes calls Console.Beep() command. Just check this example:

static void Main(string[] args)
			var signals = new[]
					new UnixSignal(Signum.SIGINT),
					new UnixSignal(Signum.SIGABRT),
					new UnixSignal(Signum.SIGTERM),
					new UnixSignal(Signum.SIGUSR1),

			while (true)
				int index = UnixSignal.WaitAny(signals, 1000);

				if (index == 1000)

				Signum signal = signals[index].Signum;
				Console.WriteLine("Signal received " + signal);

You could run that program in console, then press Ctrl + C combination and you will see nothing. Then just comment Console.Beep() line and run it again. After Ctrl + C you will see: "Signal received SIGINT".

Tested on Ubuntu 14.04.3 TLS. I checked mono 4.0.3 and mono 4.2.1 and didn't see any difference.