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.\" $FreeBSD: /repoman/r/ncvs/src/lib/libc/sys/aio_return.2,v 1.19 2006/10/07 10:49:20 trhodes Exp $
.\"
.Dd May 4, 2007
.Dt AIO_RETURN 3
.Os
.Sh NAME
.Nm aio_return
.Nd retrieve return status of asynchronous I/O operation (REALTIME)
.Sh LIBRARY
.Lb librt
.Sh SYNOPSIS
.In aio.h
.Ft int
.Fn aio_return "struct aiocb *aiocbp"
.Sh DESCRIPTION
The
.Fn aio_return
system call returns the final status of the asynchronous I/O request
associated with the structure pointed to by
.Fa aiocbp .
.Pp
The
.Fn aio_return
system call
should only be called once, to obtain the final status of an asynchronous
I/O operation once it has completed
.Xr ( aio_error 3
returns something other than
.Er EINPROGRESS ) .
.Sh RETURN VALUES
If the asynchronous I/O request has completed, the status is returned
as described in
.Xr read 2 ,
.Xr write 2 ,
or
.Xr fsync 2 .
Otherwise,
.Fn aio_return
returns \-1 and sets
.Va errno
to indicate the error condition.
.Sh ERRORS
The
.Fn aio_return
system call will fail if:
.Bl -tag -width Er
.It Bq Er EINVAL
The
.Fa aiocbp
argument
does not reference a completed asynchronous I/O request.
.El
.Sh SEE ALSO
.Xr fsync 2 ,
.Xr read 2 ,
.Xr write 2 ,
.Xr aio_cancel 3 ,
.Xr aio_error 3 ,
.Xr aio_suspend 3 ,
.Xr aio_write 3
.Sh STANDARDS
The
.Fn aio_return
system call
is expected to conform to the
.St -p1003.1-2001
standard.
.Sh HISTORY
The
.Fn aio_return
system call first appeared in
.Nx 5.0 .