Fix hanging process (kill of parent process leaves child as a zombie)

Fix hanging process (kill of parent process leaves child as a zombie)

R=nweiz@google.com

Committed: https://code.google.com/p/dart/source/detail?r=45026

[Siggi Cherem (dart-lang), 2015-04-09 17:58:07]

sigmund@google.com changed reviewers:
+ kevmoo@google.com, nweiz@google.com

[nweiz, 2015-04-09 18:29:04]

https://codereview.chromium.org/1075963002/diff/20001/sdk/lib/_internal/pub/t...
File sdk/lib/_internal/pub/test/run/forwards_signal_posix_test.dart (right):

https://codereview.chromium.org/1075963002/diff/20001/sdk/lib/_internal/pub/t...
sdk/lib/_internal/pub/test/run/forwards_signal_posix_test.dart:32:
ProcessSignal.SIGWINCH.watch().listen(printAndCountdown);
I think a slightly-cleaner way to do this could be to write something like:

void _printSignal(ProcessSignal signal) {
  var subscription;
  subscription = signal.watch().listen((_) {
    print(signal);
    subscription.cancel();
  });
}

and then use that for all the signals.

https://codereview.chromium.org/1075963002/diff/20001/sdk/lib/_internal/pub/t...
File sdk/lib/_internal/pub/test/run/forwards_signal_windows_test.dart (right):

https://codereview.chromium.org/1075963002/diff/20001/sdk/lib/_internal/pub/t...
sdk/lib/_internal/pub/test/run/forwards_signal_windows_test.dart:14:
ProcessSignal.SIGHUP.watch().listen((s) { print(s); exit(0); });
Nits: use "signal" rather than "s", put each statement on its own line.

[Siggi Cherem (dart-lang), 2015-04-09 18:42:22]

ptal

https://codereview.chromium.org/1075963002/diff/20001/sdk/lib/_internal/pub/t...
File sdk/lib/_internal/pub/test/run/forwards_signal_posix_test.dart (right):

https://codereview.chromium.org/1075963002/diff/20001/sdk/lib/_internal/pub/t...
sdk/lib/_internal/pub/test/run/forwards_signal_posix_test.dart:32:
ProcessSignal.SIGWINCH.watch().listen(printAndCountdown);
On 2015/04/09 18:29:04, nweiz wrote:
> I think a slightly-cleaner way to do this could be to write something like:
> 
> void _printSignal(ProcessSignal signal) {
>   var subscription;
>   subscription = signal.watch().listen((_) {
>     print(signal);
>     subscription.cancel();
>   });
> }
> 
> and then use that for all the signals.

oh, that gave me the idea of just using `.first` on the stream. WDYT?

[nweiz, 2015-04-09 18:46:07]

lgtm!

Thanks for fixing my bugs, Siggi!

https://codereview.chromium.org/1075963002/diff/20001/sdk/lib/_internal/pub/t...
File sdk/lib/_internal/pub/test/run/forwards_signal_posix_test.dart (right):

https://codereview.chromium.org/1075963002/diff/20001/sdk/lib/_internal/pub/t...
sdk/lib/_internal/pub/test/run/forwards_signal_posix_test.dart:32:
ProcessSignal.SIGWINCH.watch().listen(printAndCountdown);
On 2015/04/09 18:42:21, Siggi Cherem (dart-lang) wrote:
> On 2015/04/09 18:29:04, nweiz wrote:
> > I think a slightly-cleaner way to do this could be to write something like:
> > 
> > void _printSignal(ProcessSignal signal) {
> >   var subscription;
> >   subscription = signal.watch().listen((_) {
> >     print(signal);
> >     subscription.cancel();
> >   });
> > }
> > 
> > and then use that for all the signals.
> 
> oh, that gave me the idea of just using `.first` on the stream. WDYT?

SGTM

[Siggi Cherem (dart-lang), 2015-04-09 18:49:45]

Committed patchset #3 (id:40001) manually as 45026 (presubmit successful).