Intel 121748-001 manual Overlay Attr

8086 Object Module Formats Version 4."

OVERLAY DEFINITION RECORD

(OVLDEFf ---- --

***********************///*********1 1'1*********///***********

*		*		*		*		*		*	*
*	REC	*	RECORD	*	OVERLAY	..	OVERLAY	*	OVERLAY	*	CHK *
*	TYP *		LENG'fH	*	NAME	*	LOCATION	*	ATTR	*	SUM *
*	70H	*		*		*		*		*	*
*		*		*		*		*		*	*

***********************///*********~ 111*********///***********

This Record provides the overlay name, the location of the

overlay in the object file, and the attributes of the overlay. A loader may use this record to locate the data records of the overlay in the object file .

OVERLA~(NAME

The OVERLAY NAME field provides a name by which a collection of 1 or more LSEG's and/or Groups may be referenced for load ina.

The ordering of OVLOEF Records within a module induces an

ordering on the set of all Overlays defined in the module. Thus, OVLDEF records are considered to be numbered: 1, 2, 3, 4, •••

These numbers are used as dOverlay Indices· in the OVERLAY ATTR field of followinq OVLDEF records.

Overlay indices may not be forward referrinq. That is to say, an overlay definition record defininq the kith overlay must precede any record referrinci to that overlay with index k.

OVERLAY LOCATION

The OVERLAY LOCATIO~ is a 4-byte field which ~ives the location in bytes relative to the start of the file of the first byte of the records in the overlay.

OVERLAY ATTR

The OVERLAY ATTR field has the followino format:

***********///*********///*****

*	*	SHARED	*	ADJACENT	*
*	*		*		*
* SA * OVERLAY * OVERLAY *
*	*	INDEX	*	INDEX	*
*	*		*		*
***********///*********///*****
	I		I		I

+conditional+conditionnl+

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