c++ - How can I access dynamically created objects which are created out of the scope of the current function? -

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i want pass uninitialized object pointer method. within method i'll create instance of object using new operator (or malloc) , assign address passed pointer. part of code:

void test(testclass* t){     ...     t = new testclass();     ... }  int _tmain(int argc, _tchar* argv[]) {     testclass* t = null;     test(t);     cout<<t->gettestvalue()<<endl;     delete t; }

my problem in _tmain function (after calling test) want call gettestvalue method of object pointed t. here program crashes , terminates access violation unexpected exception.

it seems object created dynamically (using operator new , malloc) not usable outsie of scope of function test. can help?

to change pointer in function, must passed reference:

void test(testclass*& t)

otherwise, change made inside function not visible on outside.

your original pointer doesn't changed, remains null, , runs undefined behavior , crash.

whenever pass parameter value, copy made inside function. when t = new testclass();, you're working on copy of pointer.


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