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 struct file *fp Ft int Fn VOP_CLOSE struct vnode *vp int mode struct ucred *cred struct thread *td

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.

The arguments are:

Fa vp

The vnode of the file.

Fa mode

The access mode required by the calling process.

Fa cred

The caller's credentials.

Fa td

The thread which is accessing the file.

Fa fp

The file being opened.

Pointer to the file Fa fp is useful for file systems which require such information, e.g., fdescfs(5). Use `NULL' as Fa fp argument to Fn VOP_OPEN for in-kernel opens.

The access mode is a set of flags, including FREAD FWRITE O_NONBLOCK O_APPEND

LOCKS

Fn VOP_OPEN expects Fa vp to be locked on entry and will leave it locked on return.

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.

RETURN VALUES

Zero is returned on success, otherwise an error code is returned.

AUTHORS

This manual page was written by An Doug Rabson .