LU 6.2 API Application Programmer's Reference Guide (30294-90008)

198 AppendixE
Transact Parameter Masks
The Parameter Mask
The Parameter Mask
The parameter mask, or bit mask, is a string of bits, each corresponding
to an intrinsic parameter. The leftmost bit corresponds to the first
parameter in the intrinsic call. If a bit is set to 1, the corresponding
parameter is passed, and if the bit is set to 0 the parameter is omitted.
For intrinsics with up to 16 parameters, a 16-bit mask is used. For
intrinsics with 17 through 32 parameters, a 32-bit mask is used.
Parameters for Future Expansion
To allow for future expansion on MPE V, all LU 6.2 API intrinsics
contain additional parameters that are not documented in this manual.
When coding the bit mask, you must account for these “hidden”
parameters as well as the documented parameters. In the future, if the
hidden parameters are implemented, you will not have to change and
re-compile your TP.
Parameter Mask Templates
Table E-1 and Table E-2 describe the parameter mask for each intrinsic.
Table E-1 lists the intrinsics that require 16-bit masks
The parameter mask templates for each intrinsic indicate which bits
correspond to required, optional, and hidden parameters. Required
parameters are represented by 1’s, and hidden parameters are
represented by 0’s. Optional parameters are represented by x’s in the
templates, and you must replace them with 0's or 1's when you code the
parameter mask into your TP. If you are passing an optional parameter,
put a 1 in the corresponding bit of the parameter mask, and if you are
omitting it, put a 0 in the bit mask.
After you replace every x with a 0 or 1, translate the bit string to a
decimal value to be coded into your TP. For intrinsics with no optional
parameters, the mask value will always be the same and is given in the
“Mask Constant” column.