A Dart package that constantly writes a string to an
IOSink, simillarly to the UNIX
// Write to stdout for 5 seconds. final controller = yes(stdout, message); await Future<void>.delayed(const Duration(seconds: 5)); controller.cancel();
// Write to a process's stdin for 5 seconds, and kill it. // Wait for the yes operation to complete (which occurs when stdin closes) // before continuing. final process = await Process.start('cat', const ); process.stdout.pipe(stdout); final controller = yes(process.stdin); Future.delayed(const Duration(seconds: 5)) .then((_) => process.kill(ProcessSignal.sigint)); await controller.done; print('Done!');
A complete UNIX
yes utility clone can be found in the example project.
In order not to block the event loop, one write at most is performed each loop. While this should be fine in most cases, output speed is severely bottlenecked. This can be mitigated by repeating the given message several times:
Additionally, by default, the given
flush future is considered as possibly synchronous, so an additional event loop loop is added to prevent the event loop from blocking. If the
flush future is guaranteed to be asynchronous, then the additional loop can be avoided.
yes(stdout, 'y', false);
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