pplx task cancellation on linux

[slepasteur]

I tried to execute the cancelling parallel tasks exemple on linux but it didn't work (the task was never canceled).

Here is the output:
Creating task...
Performing work...
Performing work...
Performing work...
Performing work...
Canceling task...
Waiting for task to complete...
Performing work...
Performing work...
Performing work...
Performing work...
Performing work...
...

[ras0219-msft]

This sounds like a bug. I'll mark it for investigation.

[mmthomas]

This is a known issue with pplx when not interoperating with the MS concurrency libraries (i.e., if CPPREST_FORCE_PPLX is defined). The call to is_task_cancellation_requested() always returns false (and is documented as such in the code).

The workaround is to instead capture the cancellation token into your lambda expression, and check token.is_canceled() to decide whether or not to cancel the task.