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.