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vop_ioctl(9) [posix man page]

VOP_IOCTL(9)						   BSD Kernel Developer's Manual					      VOP_IOCTL(9)

NAME
VOP_IOCTL -- device specific control SYNOPSIS
#include <sys/param.h> #include <sys/vnode.h> int VOP_IOCTL(struct vnode *vp, u_long command, caddr_t data, int fflag, struct ucred *cred, struct thread *td); DESCRIPTION
Manipulate a file in device dependent ways. Its arguments are: vp The vnode of the file (normally representing a device). command The device specific operation to perform. data Extra data for the specified operation. fflag Some flags ??? cred The caller's credentials. td The calling thread. Most file systems do not implement this entry point. LOCKS
The file should not be locked on entry. RETURN VALUES
If successful, zero is returned, otherwise an appropriate error code. If the ioctl is not recognized or not handled, ENOTTY should be returned. SEE ALSO
vnode(9) AUTHORS
This manual page was written by Doug Rabson. BSD
July 24, 1996 BSD

Check Out this Related Man Page

VOP_OPEN(9)						   BSD Kernel Developer's Manual					       VOP_OPEN(9)

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 fin- ished 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. BSD
December 2, 2009 BSD

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