AIO_WAITCOMPLETE(2)       FreeBSD System Calls Manual      AIO_WAITCOMPLETE(2)

NAME
     aio_waitcomplete - wait for the next completion of an aio request

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <aio.h>

     ssize_t
     aio_waitcomplete(struct aiocb **iocbp, struct timespec *timeout);

DESCRIPTION
     The aio_waitcomplete() system call waits for completion of an
     asynchronous I/O request.  Upon completion, aio_waitcomplete() returns
     the result of the function and sets iocbp to point to the structure
     associated with the original request.  If an asynchronous I/O request is
     completed before aio_waitcomplete() is called, it returns immediately
     with the completed request.

     If timeout is a non-NULL pointer, it specifies a maximum interval to wait
     for a asynchronous I/O request to complete.  If timeout is a NULL
     pointer, aio_waitcomplete() waits indefinitely.  To effect a poll, the
     timeout argument should be non-NULL, pointing to a zero-valued timeval
     structure.

     The aio_waitcomplete() system call also serves the function of
     aio_return(), thus aio_return() should not be called for the control
     block returned in iocbp.

RETURN VALUES
     If an asynchronous I/O request has completed, iocbp is set to point to
     the control block passed with the original request, and the status is
     returned as described in read(2), write(2), or fsync(2).  On failure,
     aio_waitcomplete() returns -1, sets iocbp to NULL and sets errno to
     indicate the error condition.

ERRORS
     The aio_waitcomplete() system call fails if:

     [EINVAL]           The specified time limit is invalid.

     [EAGAIN]           The process has not yet called aio_read() or
                        aio_write().

     [EINTR]            A signal was delivered before the timeout expired and
                        before any asynchronous I/O requests completed.

     [EWOULDBLOCK]

     [EINPROGRESS]      The specified time limit expired before any
                        asynchronous I/O requests completed.

SEE ALSO
     aio_cancel(2), aio_error(2), aio_read(2), aio_return(2), aio_suspend(2),
     aio_write(2), fsync(2), read(2), write(2), aio(4)

STANDARDS
     The aio_waitcomplete() system call is a FreeBSD-specific extension.

HISTORY
     The aio_waitcomplete() system call first appeared in FreeBSD 4.0.

AUTHORS
     The aio_waitcomplete() system call and this manual page were written by
     Christopher M Sedore <cmsedore@maxwell.syr.edu>.

FreeBSD 13.1-RELEASE-p6         March 21, 2016         FreeBSD 13.1-RELEASE-p6