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QuestionUsing 宝 in _RecordsetPtr, without setting Chinese IME in my windows Pin
leesense19-Apr-09 16:54
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Questionchar+char issues Pin
gamefreak229119-Apr-09 14:39
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AnswerRe: char+char issues Pin
aks.19-Apr-09 18:59
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gamefreak229119-Apr-09 19:32
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Questionactivex dll problem [solved] Pin
maxMESA19-Apr-09 0:48
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AnswerRe: activex dll problem Pin
Stuart Dootson19-Apr-09 1:47
professionalStuart Dootson19-Apr-09 1:47 
AnswerRe: activex dll problem Pin
maxMESA19-Apr-09 7:14
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Questionpoint reference VS value Pin
sharion18-Apr-09 21:18
sharion18-Apr-09 21:18 
We know that when point variable as parameter of function,operations done in the function to the parameter actually willl effect the variable that is passed into the function.That is called pass by reference.

Based on above viewpoint,I have an confusion. For example,
void GetMemory(char* p)
	{
		p =  new char[100];
	}
int main()
{
   char* str = NULL;
   GetMemory(str);
   /* */
}


After GetMemory(str) is complete, str is still NULL and no point variable is related to memory allocated.

About the result, one explanation is p in function GetMemory is only a copy of variable str. This explanation may be right but it seems that it contradicts pass by reference. Now that passing by reference, where is the copy come from. And operations done to variable p is equal to operations to str,why str is NULL finally.

Appreciate your kind very much and hope anyone give me a clear explanation. Thanks in advance.
AnswerRe: point reference VS value Pin
Stuart Dootson18-Apr-09 22:53
professionalStuart Dootson18-Apr-09 22:53 
GeneralRe: point reference VS value Pin
sharion19-Apr-09 1:35
sharion19-Apr-09 1:35 
GeneralRe: point reference VS value Pin
Luc Pattyn19-Apr-09 1:49
sitebuilderLuc Pattyn19-Apr-09 1:49 
GeneralRe: point reference VS value Pin
Stuart Dootson19-Apr-09 1:52
professionalStuart Dootson19-Apr-09 1:52 
GeneralRe: point reference VS value Pin
sharion19-Apr-09 3:21
sharion19-Apr-09 3:21 
GeneralRe: point reference VS value Pin
Stuart Dootson19-Apr-09 3:52
professionalStuart Dootson19-Apr-09 3:52 
GeneralRe: point reference VS value Pin
Luc Pattyn19-Apr-09 4:05
sitebuilderLuc Pattyn19-Apr-09 4:05 
GeneralRe: point reference VS value Pin
Stuart Dootson19-Apr-09 4:24
professionalStuart Dootson19-Apr-09 4:24 
GeneralRe: point reference VS value Pin
Luc Pattyn19-Apr-09 4:37
sitebuilderLuc Pattyn19-Apr-09 4:37 
GeneralRe: point reference VS value Pin
Stuart Dootson19-Apr-09 4:56
professionalStuart Dootson19-Apr-09 4:56 
GeneralRe: point reference VS value Pin
Luc Pattyn19-Apr-09 5:00
sitebuilderLuc Pattyn19-Apr-09 5:00 
GeneralRe: point reference VS value Pin
Stuart Dootson19-Apr-09 5:04
professionalStuart Dootson19-Apr-09 5:04 
GeneralRe: point reference VS value Pin
sharion19-Apr-09 5:25
sharion19-Apr-09 5:25 
GeneralRe: point reference VS value Pin
Stuart Dootson19-Apr-09 7:15
professionalStuart Dootson19-Apr-09 7:15 
GeneralRe: point reference VS value Pin
sharion20-Apr-09 18:30
sharion20-Apr-09 18:30 
GeneralRe: point reference VS value Pin
Stuart Dootson20-Apr-09 19:40
professionalStuart Dootson20-Apr-09 19:40 
GeneralRe: point reference VS value Pin
sharion21-Apr-09 18:05
sharion21-Apr-09 18:05 

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