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.\" $FreeBSD: releng/12.2/share/man/man9/VFS_SYNC.9 206622 2010-04-14 19:08:06Z uqs $
.\"
.Dd May 23, 2009
.Dt VFS_SYNC 9
.Os
.Sh NAME
.Nm VFS_SYNC
.Nd flush unwritten data
.Sh SYNOPSIS
.In sys/param.h
.In sys/mount.h
.In sys/vnode.h
.Ft int
.Fn VFS_SYNC "struct mount *mp" "int waitfor"
.Sh DESCRIPTION
The
.Fn VFS_SYNC
macro writes out all unwritten data in the file system mounted as
.Fa mp .
.Pp
The arguments it expects are:
.Bl -tag -width ".Fa waitfor"
.It Fa mp
The file system.
.It Fa waitfor
Whether the function should wait for I/O to complete.
Possible values are:
.Bl -tag -width MNT_NOWAIT
.It Dv MNT_WAIT
synchronously wait for I/O to complete
.It Dv MNT_NOWAIT
start all I/O, but do not wait for it
.It Dv MNT_LAZY
push data not written by file system syncer
.El
.El
.Pp
The
.Fn VFS_SYNC
macro calls the
.Va vfs_sync
method of the file system, which normally calls
.Xr VOP_FSYNC 9
for all the vnodes in the file system.
.Sh SEE ALSO
.Xr fsync 2 ,
.Xr sync 2 ,
.Xr VFS 9 ,
.Xr vnode 9 ,
.Xr VOP_FSYNC 9
.Sh AUTHORS
This manual page was written by
.An Doug Rabson .