NAME¶
VOP_OPEN
,
VOP_CLOSE
—
open or close a file
SYNOPSIS¶
#include
<sys/param.h>
#include
<sys/vnode.h>
int
VOP_OPEN
(
struct
vnode *vp,
int
mode,
struct
ucred *cred,
struct thread
*td,
struct file
*fp);
int
VOP_CLOSE
(
struct
vnode *vp,
int
mode,
struct
ucred *cred,
struct thread
*td);
DESCRIPTION¶
The
VOP_OPEN
() entry point is called before a
file is accessed by a process and the
VOP_CLOSE
() entry point is called after a
file is finished with by the process.
The arguments are:
- vp
- The vnode of the file.
- mode
- The access mode required by the calling process.
- cred
- The caller's credentials.
- td
- The thread which is accessing the file.
- fp
- The file being opened.
Pointer to the file
fp is useful for file
systems which require such information, e.g.,
fdescfs(5). Use
‘
NULL
’ as
fp argument to
VOP_OPEN
() for in-kernel opens.
The access mode is a set of flags, including
FREAD
,
FWRITE
,
O_NONBLOCK
,
O_APPEND
.
LOCKS¶
VOP_OPEN
() expects
vp to be locked on entry and will leave it
locked on return.
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
vn_close expects an unlocked, referenced
vnode and will dereference the vnode prior to returning.
RETURN VALUES¶
Zero is returned on success, otherwise an error code is returned.
SEE ALSO¶
vnode(9),
VOP_LOOKUP(9)
AUTHORS¶
This manual page was written by
Doug
Rabson.