xref: /freebsd/share/man/man9/VOP_OPENCLOSE.9 (revision ce834215a70ff69e7e222827437116eee2f9ac6f)
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3.\" Copyright (c) 1996 Doug Rabson
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29.\" $Id: VOP_OPENCLOSE.9,v 1.2 1997/03/04 10:02:15 dfr Exp $
30.\"
31.Dd July 24, 1996
32.Os
33.Dt VOP_OPEN 9
34.Sh NAME
35.Nm VOP_OPEN ,
36.Nm VOP_CLOSE
37.Nd open or close a file
38.Sh SYNOPSIS
39.Fd #include <sys/param.h>
40.Fd #include <sys/vnode.h>
41.Ft int
42.Fn VOP_OPEN "struct vnode *vp" "int mode" "struct ucred *cred" "struct proc *p"
43.Ft int
44.Fn VOP_CLOSE "struct vnode *vp" "int mode" "struct ucred *cred" "struct proc *p"
45.Sh DESCRIPTION
46The
47.Xr VOP_OPEN 9
48entry point is called before a file is accessed by a process and the
49.Xr VOP_CLOSE 9
50entry point is called after a file is finished with by the process.
51.Pp
52The arguments are:
53.Bl -tag -width mode
54.It Ar vp
55the vnode of the file
56.It Ar mode
57the access mode required by the calling process
58.It Ar p
59the process which is accessing the file
60.El
61.Pp
62The access mode is a set of flags, including
63.Dv FREAD ,
64.Dv FWRITE ,
65.Dv O_NONBLOCK ,
66.Dv O_APPEND .
67.Sh LOCKS
68The vnode
69.Fa vp
70should be locked on entry and will still be locked on exit for
71.Xr VOP_OPEN 9
72and unlocked on entry and exit for
73.Xr VOP_CLOSE 9 .
74.Sh RETURN VALUES
75Zero is returned on success, otherwise an error code is returned.
76.Sh PSEUDOCODE
77.Bd -literal
78int
79vop_open(struct vnode *vp, int mode, struct ucred *cred, struct proc *p)
80{
81    /*
82     * Most filesystems don't do much here.
83     */
84    return 0;
85}
86.Ed
87.Sh SEE ALSO
88.Xr vnode 9 ,
89.Xr VOP_LOOKUP 9
90.Sh AUTHORS
91This man page was written by Doug Rabson.
92
93