dnlc.h

<B>Digital的Unix操作系统VAX 4.2源码</B>

/*	@(#)dnlc.h	4.1	(ULTRIX)	7/2/90	*/

/************************************************************************
 *									*
 *			Copyright (c) 1986 by				*
 *		Digital Equipment Corporation, Maynard, MA		*
 *			All rights reserved.				*
 *									*
 *   This software is furnished under a license and may be used and	*
 *   copied  only  in accordance with the terms of such license and	*
 *   with the  inclusion  of  the  above  copyright  notice.   This	*
 *   software  or  any  other copies thereof may not be provided or	*
 *   otherwise made available to any other person.  No title to and	*
 *   ownership of the software is hereby transferred.			*
 *									*
 *   This software is  derived  from  software  received  from  the	*
 *   University    of   California,   Berkeley,   and   from   Bell	*
 *   Laboratories.  Use, duplication, or disclosure is  subject  to	*
 *   restrictions  under  license  agreements  with  University  of	*
 *   California and with AT&T.						*
 *									*
 *   The information in this software is subject to change  without	*
 *   notice  and should not be construed as a commitment by Digital	*
 *   Equipment Corporation.						*
 *									*
 *   Digital assumes no responsibility for the use  or  reliability	*
 *   of its software on equipment which is not supplied by Digital.	*
 *									*
 ************************************************************************/

/*
 *	Portions of this software have been licensed to 
 *	Digital Equipment Company, Maynard, MA.
 *	Copyright (c) 1986 Sun Microsystems, Inc.  ALL RIGHTS RESERVED.
 */

/*
 * This structure describes the elements in the cache of recent
 * names looked up.
 */

#define	NC_NAMLEN	15	/* maximum name segment length we bother with*/

struct	ncache {
	struct	ncache	*hash1_next, *hash1_prev;/* lookup hash chain */
	struct	ncache	*hash2_next, *hash2_prev;/* parent vnode hash chain */
	struct	ncache	*hash3_next, *hash3_prev;/* looked up vnode hash chain*/
	struct 	ncache	*lru_next, *lru_prev;	/* LRU chain */
	struct	vnode	*vp;			/* vnode the name refers to */
	struct	vnode	*dp;			/* vno of parent of name */
	char		namlen;			/* length of name */
	char		name[NC_NAMLEN];	/* segment name */
	struct	ucred	*cred;			/* credentials */
};

#define	ANYCRED	((struct ucred *) -1)
#define	NOCRED	((struct ucred *) 0)