--- In [email protected], "Jimmy J. Johnson" <boxer...@...> wrote:
>
> I know this is really basic for everyone here, but I have not
> used C++ in years and need a little help understanding what
> this signature for the header file is telling me.
>
> This is from the Fantom API for the Lego Mindstorms robot.
>
> nFANTOM100_kExport static iNXTIterator* _VI_FUNCC
> createNXTIterator(
> ViBoolean searchBluetooth, ViUInt32
> bluetoothSearchTimeoutInSeconds,
> tStatus& status );
>
>
> 1. What is nFANTOM100_kExport?
It's a macro conditionally defined in platform.h...
#ifdef nFANTOM100_kExportSymbols
#define nFANTOM100_kExport __attribute__ ((section ("__TEXT,__export")))
#else
#define nFANTOM100_kExport
#endif
> 2. What does "static" mean in this context?
You haven't shown the context![1] You've only shown the function
declarator. But in the full context, inside a class declaration,
it means the function is not tied to a specific instance of
an iNXT object, but is a 'global' function owned by the iNXT
class.
[1] The static keyword has almost a dozen different meanings
in different contexts!
> 3. What is "_VI_FUNCC"?
It's a macro conditionally defined in visatype.h e.g. for
WIN32 implementations...
#define _VI_FUNCC __cdecl
It relates to calling conventions. The library has C linkage.
> 4. What is a "ViBoolean" and "ViUInt32" as opposed to a
> boolean or unsigned integer?
It's a platform dependant typedef (type synonym) conditionally
defined in visatype.h.
> 5. What is the "&" on tStatus? Does that mean it take
> the "address of" or reference to a tStatus object and
> not the object itself?
It means status is a reference to an object of type tStatus,
not a copy of one. [Pass by reference, not value.]
--
Peter
