On Jun 29, 2011, at 10:56 AM CDT, Jeff Squyres wrote:
> There's probably an alignment gap between the short and char array, and possibly an alignment gap between the char array and the double array (depending on the value of SHORT_INPUT and your architecture).
> So for your displacements, you should probably actually measure what the displacements are instead of using sizeof(short), for example.
> tVStruct foo;
> aiDispsT5 = 0;
> aiDispsT5 = ((char*) &(foo.sCapacityFile) - (char*) &foo);
There's a C-standard "offsetof" macro for this calculation. Using it instead of the pointer math above greatly improves readability: http://en.wikipedia.org/wiki/Offsetof
So the second line becomes:
aiDispsT5 = offsetof(tVStruct, sCapacityFile);