[ofiwg] Man pages question

Hefty, Sean sean.hefty at intel.com
Fri Aug 14 09:46:09 PDT 2015

> Ok, but when you say that ret==0 means "cancel request was started" does
> it imply that the request WILL be successfully canceled later on? Or the
> failure still may happen?

A failure to cancel may still happen.  Cancel is racy.  Without enforcing a specific implementation, there's no way for a provider to know that the request isn't sitting complete on some other queue, or that the data that would complete hasn't already been received.  In either example, the request could complete successfully, meaning that the cancel will fail.

What cannot happen after cancel has been called is for the request to remain outstanding indefinitely.  If an app knows that *nothing* will act upon the request to change its state, then fi_cancel returning 0 should result in the request completing as canceled.

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