MPE/iX Intrinsics Reference Manual (32650-90875)

96 Chapter4
Command Definitions (ABORTSESS - FCLOSE)
DLSIZE
DLSIZE
NM and CM callable.
Causes the area between DL and DB in the compatibility mode (CM) stack to be expanded
or contracted within the CM stack segment.
Syntax
I16 I16V
dldbsize :=DLSIZE( size );
Functional Return
dldbsize 16-bit signed integer (assigned functional return)
Returns the granted number of half words for the DL-to-DB area. This
value is negative, unless error condition CCL (1) is returned; a positive
value is possible.
Parameters
size 16-bit signed integer by value (required)
Passes the desired number of half words for the DL-to-DB area,
represented by a negative value. A
size of 0 is permitted and resets the
DL-to-DB area of the CM stack to the original value assigned when the
process was created (initial DL). The size granted is the absolute value of
size , rounded up so that the distance between the beginning of the
segment and DB is a multiple of 128 half words.
Operation Notes
If expanding, all information in the area between DL and DB is saved. If contracting, all
information in the area between DL and DB is lost.
If the DL area has been expanded, it can be contracted by calling DLSIZE with a
size
parameter requesting a smaller DL-to-DB area.
When called from programs running in NM the DLSIZE intrinsic affects the CM stack only;
programmatic expansion and contraction in NM is not necessary.
CAUTION Because of differences between DB-relative addressing (used in compatibility
mode) and virtual addressing (used in native mode), calls to the DLSIZE
intrinsic in mixed mode programming may cause stack corruption.
Hewlett-Packard does not recommend using the DLSIZE intrinsic in programs
that move between Native mode and compatibility mode.