100 lines
2.9 KiB
Groff
100 lines
2.9 KiB
Groff
.\" -*- nroff -*-
|
|
.\"
|
|
.\" Copyright (c) 1996 Doug Rabson
|
|
.\"
|
|
.\" All rights reserved.
|
|
.\"
|
|
.\" This program is free software.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR
|
|
.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
|
.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
|
|
.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT,
|
|
.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
|
|
.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
|
|
.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
.\"
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd July 24, 1996
|
|
.Os
|
|
.Dt VOP_OPEN 9
|
|
.Sh NAME
|
|
.Nm VOP_OPEN ,
|
|
.Nm VOP_CLOSE
|
|
.Nd open or close a file
|
|
.Sh SYNOPSIS
|
|
.In sys/param.h
|
|
.In sys/vnode.h
|
|
.Ft int
|
|
.Fn VOP_OPEN "struct vnode *vp" "int mode" "struct ucred *cred" "struct thread *td"
|
|
.Ft int
|
|
.Fn VOP_CLOSE "struct vnode *vp" "int mode" "struct ucred *cred" "struct thread *td"
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Fn VOP_OPEN
|
|
entry point is called before a file is accessed by a process and the
|
|
.Fn VOP_CLOSE
|
|
entry point is called after a file is finished with by the process.
|
|
.Pp
|
|
The arguments are:
|
|
.Bl -tag -width mode
|
|
.It Fa vp
|
|
the vnode of the file
|
|
.It Fa mode
|
|
the access mode required by the calling process
|
|
.It Fa td
|
|
the thread which is accessing the file
|
|
.El
|
|
.Pp
|
|
The access mode is a set of flags, including
|
|
.Dv FREAD ,
|
|
.Dv FWRITE ,
|
|
.Dv O_NONBLOCK ,
|
|
.Dv O_APPEND .
|
|
.Sh LOCKS
|
|
.Fn VOP_OPEN
|
|
expects
|
|
.Fa vp
|
|
to be locked on entry and will leave it locked on return.
|
|
.Pp
|
|
.Fn VOP_CLOSE
|
|
expects at least a reference to be associated with the vnode and does not
|
|
care whether the vnode is locked or not.
|
|
The lock and reference state is left unchanged on return.
|
|
Note that
|
|
.Fa vn_close
|
|
expects an unlocked, referenced vnode and will dereference the vnode prior
|
|
to returning.
|
|
.Sh RETURN VALUES
|
|
Zero is returned on success, otherwise an error code is returned.
|
|
.Sh PSEUDOCODE
|
|
.Bd -literal
|
|
int
|
|
vop_open(struct vnode *vp, int mode, struct ucred *cred, struct thread *td)
|
|
{
|
|
/*
|
|
* Most file systems don't do much here.
|
|
*/
|
|
return 0;
|
|
}
|
|
.Ed
|
|
.Sh SEE ALSO
|
|
.Xr vnode 9 ,
|
|
.Xr VOP_LOOKUP 9
|
|
.Sh AUTHORS
|
|
This man page was written by
|
|
.An Doug Rabson .
|