Tandy 600 Programmer's Reference Manual page 9

INT
44h
-
Free
AMI
File
Space
AX
BX
CX
DX
SP:
BP:
SI:
Dl:
IP:
FLG
CS
DS
SS
ES
XXXXXXXX XXXXXXXX
XXXXXXXX XXXXXXXX
Entry:
CX
-
Number
paragraphs
of
memory
needed
Exit:
AX
-
Number
of
paragraphs
of
memory
released
This
hook
is
provided as
a mechanism
for
the
HH
O/S
to
request
that
an
application
program
release
memory
space
from
its
AMI.
Whenever
a
memory
request
has occurred during the
execution
of
an O/S
function
call,
and
there
is
not
sufficient free
memory
to
satisfy
the
request,
HH
O/S
will
invoke
this interrupt with
parameters specifying the
amount
of
additional
memory
required
to satisfy
the
memory
request.
The
application
program
may
then
free
up
memory
in its
AMI
file
if
possible,
and
return to
HH
O/S
informing
it
of
how much memory may
be recovered from
the
AMI
file.
Some
programs
may
run
more
efficiently
if
they
can
initially
allocate
a
large
block of
memory
to their
AMI, and
then incrementally release
it
back
to
the
system
as
required.
This
hook
is
provided
to
support
such
applications.
It
is
never necessary
for
an
application
program
to
use
this
hook
vector.
On
entry,
CX
will
specify the
number
of
paragraphs
of
memory
that the
O/S
requires
to
complete the current
memory
request.
The segment
registers
DS
and
ES
will
contain the
same
value as
on
the
original
entry
to
the
O/S
function being executed.
The
stack
registers
SS
and
SP
will
point
to
the stack that
was
in
effect
on
entry
to
the
O/S
function.