Tandy 600 Programmer's Reference Manual page 104

Function 15h
-
Begin Query
Definition
Parameter Block:
00
FILE_HANDLE
File Identifier
01
MODE
Query
definition
mode
02
BUFFEFLLENGTH
Size
of
query
definition buffer
03
BUFFER
Offset of
query key
buffer
04
BUFFER_SEGMENT
Segment
of
query key
buffer
Returr
AX:
i
Value:
STATUS Error
Code
The
FILEHANDLE
parameter
specifies the
opened
database
file
for
which
the
query
is
to
be
defined.
The
MODE
parameter
may
be
either or
1
.
In
mode
0,
the
query key
is
not
built,
but
the size
of
the
query key
is
determined.
In
this
case, the buffer
must be
at
least
16
bytes long.
In
mode
1,
the
query key
is
actually
built. In
this
case, the buffer
must be
large
enough
to
contain the
query key
being
built.
The
size
required
may
be
determined by
making a complete
pass through
the
query
definition in
mode
0.
When
the
query
definition
is
closed, the
total
size
of
the
query
is
returned.
This
much space can
then
be
allocated for
the buffer,
and then
another
pass
made
in
mode
1
to
define the
query
key.
The
BUFFERLENGTH
parameter
specifies
the size
of
the buffer.
The
BUFFER
and
BUFFERSEGMENT
parameters specify the
segment and
offset to the buffer
which contains the
query key being defined.
Error
Returns:
99