Prototype and description of the function getntvrefbelong()

(Function of the unlock requiring group "NTv2 grid data")

 

getntvrefbelong()
Determination of the second, to a NTv2 file belonging Reference System.

Prototype of the DLL function in C++ syntax (attend lower case!):
extern "C" __declspec(dllexport) unsigned long __stdcall getntvrefbelong(
     unsigned short wRefSys,
     unsigned short *wRefNtvB);

Prototype of the DLL function in Visual Objects syntax:
_DLL function getntvrefbelong(;
     wRefSys as word,;                     // 2 Byte
     wRefNtvB ref word);                   // 4 Byte
as logic pascal:geodll32.getntvrefbelong   // 4 Byte


The function returns for the NTv2 Reference System wRefSys the second
NTv2 Reference System beonging to the NTv2 file in wRefNtvB.

The parameters are passed and/or returned as follows:
wRefSys     Geodetic Reference System, belonging to a NTv2 grid file, for
            which the second NTv2 Reference System is to be determined.
            The available Reference Systems are specified in the list
            "Coordinate Reference Systems".

wRefNtvB    The number of the determined second NTv2 Reference System.
(ref)       The number of the geodetic Reference System is returned by
            reference.

returnVal   In case of an error the function returns FALSE, otherwise TRUE.


Unlocking
This function is a component of the unlock requiring function group
"NTv2 grid data". It is unlocked for unrestricted use together with the
other functions of the group by passing the unlock parameters, acquired
from the software distribution company, trough the function setunlockcode().
Without unlocking only a few function calls for test purposes (shareware
principle) are possible. It should be noted that in addition the function
group "Coordinate Transformations" must be unlocked.