You could have the answer there. I *was* using Borland's C++ Builder. I'm getting a bit frustrated with my lack of memory, but I have got what i was trying to do working.
Thanks for the help
Roy...

OK, OK. Now I feel stupid. My old memory remembered it wrong. I think all that I was doing was getting the size of the structure not actually allocating to it. Gotta admit this getting old thing is not for wimps. I haven't done any programming except for minor little things for about 10 years and I am finding that I have forgotten most of what I ever knew, if I ever really knew it. Also I'm finding that gcc is a lot more fussy that the old...

I think you are missing the point of the question. There is no problem getting the size of the structure at run time, what I am trying to do is get the size at compile time and store that value in the structure itself; ie mys.size == sizeof(mys). This would probably require that the preprocessor make 2 passes so that the struct size is known. There should be some symbol that equates to the location at the start of the structure (data pointer?)...

I have seen this before and know it works (at least on an old Borland compiler). Unfortunately, though my memory is good, it's short. Using gcc how do I (can I?) initialize TESTSTRUCT.ssiz e to sizeof(TESTSTRU CT) at compile time?

first data location counter = ??

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