xref: /freebsd/share/man/man9/VOP_OPENCLOSE.9 (revision 952d112864d8008aa87278a30a539d888a8493cd)
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3.\" Copyright (c) 1996 Doug Rabson
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29.\" $Id: VOP_OPENCLOSE.9,v 1.1 1997/03/03 18:00:28 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/vnode.h>
40.Ft int
41.Fn VOP_OPEN "struct vnode *vp" "int mode" "struct ucred *cred" "struct proc *p"
42.Ft int
43.Fn VOP_CLOSE "struct vnode *vp" "int mode" "struct ucred *cred" "struct proc *p"
44.Sh DESCRIPTION
45The
46.Xr VOP_OPEN 9
47entry point is called before a file is accessed by a process and the
48.Xr VOP_CLOSE 9
49entry point is called after a file is finished with by the process.
50.Pp
51The arguments are:
52.Bl -tag -width mode
53.It Ar vp
54the vnode of the file
55.It Ar mode
56the access mode required by the calling process
57.It Ar p
58the process which is accessing the file
59.El
60.Pp
61The access mode is a set of flags, including
62.Dv FREAD ,
63.Dv FWRITE ,
64.Dv O_NONBLOCK ,
65.Dv O_APPEND .
66.Sh LOCKS
67The vnode
68.Fa vp
69should be locked on entry and will still be locked on exit for
70.Xr VOP_OPEN 9
71and unlocked on entry and exit for
72.Xr VOP_CLOSE 9 .
73.Sh RETURN VALUES
74Zero is returned on success, otherwise an error code is returned.
75.Sh PSEUDOCODE
76.Bd -literal
77int
78vop_open(struct vnode *vp, int mode, struct ucred *cred, struct proc *p)
79{
80    /*
81     * Most filesystems don't do much here.
82     */
83    return 0;
84}
85.Ed
86.Sh SEE ALSO
87.Xr vnode 9 ,
88.Xr VOP_LOOKUP 9
89.Sh AUTHORS
90This man page was written by Doug Rabson.
91
92