aio_return man page


This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

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


#include <aio.h>

ssize_t aio_return(struct aiocb *aiocbp);


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.


The aio_return() function may fail if:

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

The following sections are informative.

See Also

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

The Base Definitions volume of POSIX.1‐2008, <aio.h>