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 #80
Topic: fork() and aio control blocks Relevant Sections: XSH fork() (rdvk#1) Page: 403 Line: 13030 Section: fork()

The spec says that no AIO request is inherited by the child after fork. It further says that after fork() and before an exec function only async-safe interfaces can be called.

Unfortunately aio_error(), aio_return(), and aio_suspend() fall into this category. It is OK to call these functions.

What isn't specified is what the state of the aio control blocks is and therefore how these functions have to behave.

One possible solution is to declare all control blocks invalid and require that EINVAL is returned. In this case add at the end of line 13030: All aio control blocks are marked invalid.

Another possibility is that all requeuests are assumed to be canceled. In this case add at the end of 13030: All outstanding AIO requests are marked as canceled.

Interpretation Response #80
The standard does not speak to this issue, and as such no conformance distinction can be made between alternative implementations based on this. This is being referred to the sponsor.

Rationale for Interpretation