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GeneralRe: Visual Studio error LNK2005: variable XXX redefined in xxx.obj Pin
Richard MacCutchan29-Nov-15 22:22
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GeneralRe: Visual Studio error LNK2005: variable XXX redefined in xxx.obj Pin
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GeneralRe: Visual Studio error LNK2005: variable XXX redefined in xxx.obj Pin
Richard MacCutchan29-Nov-15 23:38
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GeneralRe: Visual Studio error LNK2005: variable XXX redefined in xxx.obj Pin
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GeneralRe: Visual Studio error LNK2005: variable XXX redefined in xxx.obj Pin
Richard MacCutchan30-Nov-15 0:01
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Questionc langugae Pin
ravi siriki23-Nov-15 1:58
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AnswerRe: c langugae Pin
David Crow23-Nov-15 2:38
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QuestionQuestion about malloc a struct Pin
Millenia Nova20-Nov-15 16:02
MemberMillenia Nova20-Nov-15 16:02 
The code below uses a variable's type as size in malloc(). And I printf the size of //line 1, b and c to find out their sizes malloc will allocation the space for them in heap.

Question part 1:
One person told me I should use // line a's size to malloc in // #####, while the other person said I should use //line c instead. They do have the same size in printf(). Which one is correct? Why?

Question part 2:
// line b and // line c both have the same type of variable pointers, but why do they have different sizes?

struct Vector {
double *data;
size_t size;
};

int main()
{ int a, b, d;
int sz = 12;

a = sizeof(struct Vector); // line a
printf("%d\n", a); //a = 16

b = sizeof(struct Vector*); // line b
printf("%d\n", b); //b = 8

c = sizeof(*retVal); // line c
printf("%d\n\n", c); //c = 16

struct Vector *retVal = malloc (sizeof (struct Vector)); //#####
retVal->data = malloc (sz * sizeof (double));

// Set size and return.
retVal->size = sz;
printf("retVal->size: %d\n", sz);

return 0;
}

Thank you for your help. Smile | :)
AnswerRe: Question about malloc a struct Pin
Jochen Arndt20-Nov-15 21:45
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GeneralRe: Question about malloc a struct Pin
Millenia Nova21-Nov-15 21:53
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GeneralRe: Question about malloc a struct Pin
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PraiseRe: Question about malloc a struct Pin
Millenia Nova22-Nov-15 11:12
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AnswerRe: Question about malloc a struct Pin
Richard MacCutchan20-Nov-15 21:45
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QuestionMFC Printing of multiple views for a single doc Pin
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Question. Pin
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AnswerRe: Trying to port libcddb to MSVC, having issues... Pin
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QuestionRe: Trying to port libcddb to MSVC, having issues... Pin
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AnswerRe: Trying to port libcddb to MSVC, having issues... Pin
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GeneralRe: Trying to port libcddb to MSVC, having issues... Pin
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GeneralRe: Trying to port libcddb to MSVC, having issues... Pin
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GeneralRe: Trying to port libcddb to MSVC, having issues... Pin
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GeneralRe: Trying to port libcddb to MSVC, having issues... Pin
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GeneralRe: Trying to port libcddb to MSVC, having issues... Pin
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GeneralRe: Trying to port libcddb to MSVC, having issues... Pin
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