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
TheVOP_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
AUTHORS
This manual page was written by Doug Rabson.