Bug 2923 - Console.KeyAvailable doesn't work if mono is the parent process and has stdin redirected
Summary: Console.KeyAvailable doesn't work if mono is the parent process and has stdin...
Alias: None
Product: Class Libraries
Classification: Mono
Component: mscorlib ()
Version: master
Hardware: PC Mac OS
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2012-01-16 17:53 UTC by Rolf Bjarne Kvinge [MSFT]
Modified: 2012-01-16 19:16 UTC (History)
2 users (show)

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

test case (841 bytes, application/octet-stream)
2012-01-16 17:53 UTC, Rolf Bjarne Kvinge [MSFT]

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Description Rolf Bjarne Kvinge [MSFT] 2012-01-16 17:53:53 UTC
Created attachment 1209 [details]
test case

If mono runs a sub-process, redirects stdin for that subprocess, then Console.KeyAvailable doesn't work in that subprocess.

See attached test case, it is expected that the test case should exit after a couple of seconds, but it keeps printing "no key" indefinitely.
Comment 1 Miguel de Icaza [MSFT] 2012-01-16 19:11:24 UTC
I do not believe this is a bug in Console.

This sounds like we took a dependency on a feature that does not work with redirected input/output (KeyAvailable), since this is really a letter-by-letter probe, it requires the terminal driver to be configured for this mode of operation.

But standard process output redirection does not attach a complete pseudoterminal, it merely executes with no controlling terminal, so this would have never worked.

The fix is to drop the dependency on KeyAvaialble on the code that needs it.