Hi Jasen,

 > Given

 > typedef struct moo
 >   {
 >  int foo;
 >  char bar;
 >   } moo;


 > is   sizeof(moo) * 100   always the same as   sizeof(
 > moo[100] )

    I think so. I'm not at all sure that moo[100] means anything at all
unless the array of structures is declared and consequently storage is
allocated.

 > in other words does sizeof() include any slack space
 > required for
 > alignment.

    Sizeof() returns the actual number of bytes of the dingus in the
brackets. Sizeof(moo) * 100 should return 300 with byte alignment. The
sizeof(an array of 100 structures of type moo) would also depend on
alignment. However unless you change alignment within the program they
should be the same.

    This might be a dangerous assumption with modular compilation and later
linking unless you take care that all modules specify the same alignment. I
did come across this problem reading in and then interpreting a data file
compiled with PASCAL. In that case program alignment had to match the data
file.

    Darin McBride should be able to answer this off the top of his head.

Best Wishes,
Bill.

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