.\"
.\" Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved.
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.\" $FreeBSD$
.\"
.Dd November 21, 2001
.Dt VFS_GETVFS 9
.Os
.Sh NAME
.Nm vfs_getvfs
.Nd "returns a mount point given its fsid"
.Sh SYNOPSIS
.In sys/param.h
.In sys/mount.h
.Ft struct mount *
.Fn vfs_getvfs "fsid_t *fsid"
.Sh DESCRIPTION
The
.Fn vfs_getvfs
function returns the mount point structure for a filesystem given its filesystem
identifier.  The filesystem id should have been allocated by calling
.Fn vfs_getnewfsid ;
otherwise, it will not be found.
.Pp
A major user of
.Fn vfs_getvfs
is NFS, which uses the fsid as part of file handles in order to determine the
filesystem a given RPC is for.
If
.Fn vfs_getvfs
fails to find the mount point related to
.Fa fsid
the filesystem is considered stale.
.Sh RETURN VALUES
If
.Fa fsid
is found the mount point for the id is returned; otherwise,
.Dv NULL
is returned.
.Sh PSEUDOCODE
.Bd -literal
	if ((mp = vfs_getvfs(&fhp->fh_fsid)) == NULL) {
		error = ESTALE;
		goto out;
	}
.Ed
.Sh AUTHORS
This man page was written by
.An Chad David Aq davidc@acns.ab.ca .