Interpretations

Answering questions that may arise related to the meaning of portions of an IEEE standard concerning specific applications.

IEEE Standards Interpretation for IEEE Std 1003.1™-2001 IEEE Standard Standard for Information Technology -- Portable Operating System Interface (POSIX®)

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Interpretation Request #82
Topic: lio_listio() aio_sigevent Relevant Sections: XSH lio_listio()

Nowhere in the document is it stated what happens if individual I/O requests issued via lio_listio() have aio_sigevent members which specify actions other then SIGEV_NONE. It is clear that the sigevent specified in the lio_listio parameter list is used.

A simple test shows that there is a difference in existing implementations. Solaris and AIX both handle the sigevent information for the individual requests. Linux does not and only issues one event when all the work is done.

I'm willing to concede that the Solaris/AIX semantics has its benefits and am willing to change my implementation. But the spec should be extended as well.

Action:

I suggest adding a new paragraph at line 23069:

The aio_sigevent member specifies the notification which occurs when the request specified by this element of /list/ is completed.

Interpretation Response
The working group believe the standard is clear but concerns have been raised about this which are being referred to the sponsor.

Rationale for Interpretation
The working group felt that this is required but that adding further clarification could be justified for a future revision.