xref: /freebsd/share/man/man9/vfs_getvfs.9 (revision 315ee00f)
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27.Dd November 21, 2001
28.Dt VFS_GETVFS 9
29.Os
30.Sh NAME
31.Nm vfs_getvfs
32.Nd "returns a mount point given its file system identifier"
33.Sh SYNOPSIS
34.In sys/param.h
35.In sys/mount.h
36.Ft "struct mount *"
37.Fn vfs_getvfs "fsid_t *fsid"
38.Sh DESCRIPTION
39The
40.Fn vfs_getvfs
41function returns the mount point structure for a file system given its file system
42identifier.
43The file system ID should have been allocated by calling
44.Xr vfs_getnewfsid 9 ;
45otherwise, it will not be found.
46.Pp
47A major user of
48.Fn vfs_getvfs
49is NFS, which uses the
50.Vt fsid
51as part of file handles in order to determine the
52file system a given RPC is for.
53If
54.Fn vfs_getvfs
55fails to find the mount point related to
56.Fa fsid ,
57the file system is considered stale.
58.Sh RETURN VALUES
59If
60.Fa fsid
61is found, the mount point for the ID is returned; otherwise,
62.Dv NULL
63is returned.
64.Sh PSEUDOCODE
65.Bd -literal
66if ((mp = vfs_getvfs(&fhp->fh_fsid)) == NULL) {
67	error = ESTALE;
68	goto out;
69}
70.Ed
71.Sh SEE ALSO
72.Xr vfs_getnewfsid 9
73.Sh AUTHORS
74This manual page was written by
75.An Chad David Aq Mt davidc@acns.ab.ca .
76