TOPS-10 Monitor Calls Manual Volume 2 AA-K039D ... - Trailing-Edge

CORE [CALLI 11]
Before expanding core, you should compare the highest required address
with the highest legal address (stored in .JBREL). The example below
shows how to expand core only if necessary.
You can specify the beginning of your program's high segment by using
the REMAP monitor call, the /NEWPAGE or /SET switches to LINK, or the
TWOSEG pseudo-op to MACRO.
SKIP RETURN
The ac contains the current virtual memory limit in lK blocks.
However, if the CORE monitor call is issued from a non-zero section,
the virtual memory limit is not returned in the ac.
ERROR RE TURN
The error return occurs if any of the following conditiqns occurs:
a You give hiseg a value less than 400001 (or the ~iseg
origin), but you do not have write-access privileges.
a You give both hiseg and lowseg as zero. In this case, the
number of free 1K blocks is returned in the ac.
a The sum of the requested new low segment and the previously
existing high segment exceeds your allowed program size.
Core assignment is not changed; the maximum allowed program
size (in IK blocks) is returned in the ac.
a The sum of the requested new low and high segments exceeds
your allowed program size. Core assignment is not changed;
the maximum allowed program size (in 1K blocks) is returned
in the ac.
a You give a lowseg argument that would extend the low segment
into the high segment.
a
One or both segments are locked.
EXAMPLE
MOVE
PUSHJ
JRST
TI,NEWSIZ ;Set up for call
P,CHKCOR ;Call for core
CONTIN
;Subroutine to get core only if needed
CHKCOR:
RELATED
a
a
CAMG
POPJ
CORE
JRST
POPJ
CALLS
PAGE.
SEGOP.
TI, .JBREL## ;Core size OK?
P, ;Yes
TI, ;Get more core
ERROR ;To error routine
P, ;Core increase OK
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