NAME

aio_return — retrieve return status of an asynchronous I/O operation

SYNOPSIS

#include <aio.h>

ssize_t aio_return(struct aiocb *aiocbp);


DESCRIPTION

The aio_return() function shall return the return status associated with the aiocb structure referenced by the aiocbp argument. The return status for an asynchronous I/O operation is the value that would be returned by the corresponding read(), write(), or fsync() function call. If the error status for the operation is equal to [EINPROGRESS], then the return status for the operation is undefined. The aio_return() function may be called exactly once to retrieve the return status of a given asynchronous operation; thereafter, if the same aiocb structure is used in a call to aio_return() or aio_error(), an error may be returned. When the aiocb structure referred to by aiocbp is used to submit another asynchronous operation, then aio_return() may be successfully used to retrieve the return status of that operation.

RETURN VALUE

If the asynchronous I/O operation has completed, then the return status, as described for read(), write(), and fsync(), shall be returned. If the asynchronous I/O operation has not yet completed, the results of aio_return() are undefined.

If the aio_return() function fails, it shall return -1 and set errno to indicate the error.

ERRORS

The aio_return() function may fail if:

[EINVAL]

The aiocbp argument does not refer to an asynchronous operation whose return status has not yet been retrieved.

EXAMPLES

None.

APPLICATION USAGE

None.

RATIONALE

None.

FUTURE DIRECTIONS

None.

SEE ALSO

aio_cancel, aio_error, aio_fsync, aio_read, aio_write, close, exec, exit, fork, lio_listio, lseek, read

XBD <aio.h>

CHANGE HISTORY

First released in Issue 5. Included for alignment with the POSIX Realtime Extension.

Issue 6

The [ENOSYS] error condition has been removed as stubs need not be provided if an implementation does not support the Asynchronous Input and Output option.

The APPLICATION USAGE section is added.

The [EINVAL] error condition is made optional. This is for consistency with the DESCRIPTION.

Issue 7

SD5-XSH-ERN-148 is applied.

The aio_return() function is moved from the Asynchronous Input and Output option to the Base.