.\"     $OpenBSD: vwaitforio.9,v 1.10 2004/04/17 20:30:41 jmc Exp $
.\"
.\" Copyright (c) 2001 Constantine Sapuntzakis
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\"
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. The name of the author may not be used to endorse or promote products
.\"    derived from this software without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
.\" INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
.\" AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
.\" THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
.\" EXEMPLARY, OR CONSEQUENTIAL  DAMAGES (INCLUDING, BUT NOT LIMITED TO,
.\" PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
.\" OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
.\" OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
.\" ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
.\"
.Dd February 26, 2001
.Dt VWAITFORIO 9
.Os
.Sh NAME
.Nm vwaitforio
.Nd wait for all outstanding asynchronous writes
.Sh SYNOPSIS
.Fd #include <sys/types.h>
.Fd #include <sys/vnode.h>
.Ft int
.Fn "vwaitforio" "struct vnode *vp" "int slpflag" "char *wmesg" "int slptimeo"
.Sh DESCRIPTION
The
.Fn vwaitforio
call sleeps until all asynchronous writes associated with the vnode
.Fa vp
finish.
This is used by functions that need to make sure
that the writes they initiated have completed.
.Pp
The
.Fn vwaitforio
call sleeps at priority
.Dv PRIBIO
+ 1 .
The
.Fa slpflag ,
.Fa wmesg ,
and
.Fa slptimeo
arguments indicate flags to be passed to
.Xr tsleep 9 .
.Pp
This function must be called at
.Xr splbio 9 .
.Pp
It may be important to ensure that no other process submits asynchronous
writes while a process is waiting for I/O on this vnode.
Otherwise,
.Fn vwaitforio
may never return.
.\" .Pp
.\" (Vnode interlock??)
.Sh RETURN VALUES
The
.Fn vwaitforio
function returns 0 on success.
See
.Xr tsleep 9
for possible error returns.
.Sh SEE ALSO
.Xr tsleep 9 ,
.Xr vnode 9