usr/src/include/struct.h

/*-
 * Copyright (c) 1983 The Regents of the University of California.
 * All rights reserved.
 *
 * %sccs.include.redist.c%
 *
 *      @(#)struct.h    5.2 (Berkeley) %G%
 */

#ifndef _STRUCT_H_
#define _STRUCT_H_

/* Offset of the field in the structure. */
#define fldoff(name, field) \
        ((int)&(((struct name *)0)->field))

/* Size of the field in the structure. */
#define fldsiz(name, field) \
        (sizeof(((struct name *)0)->field))

/* Address of the structure from a field. */
#define strbase(name, addr, field) \
        ((struct name *)((char *)(addr) - fldoff(name, field)))

#endif /* !_STRUCT_H_ */