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Free / delete a char * causes an invalid heap pointer failure

I have a piece of code that I use to get the UNC path for the mapped drive in the CLR DLL, but when I free the memory at the end, the char array causes an invalid heap pointer statement and I assume this is due to it being allocated InteropServices, but I want to make sure that it does not turn into a memory leak, since this function is called repeatedly.

the code:

DWORD MAX_DEVICE_LENGTH = 1000;
TCHAR* szDeviceName = new TCHAR[MAX_DEVICE_LENGTH];
memset(szDeviceName, '\0', MAX_DEVICE_LENGTH); 
DWORD dwResult; 


char* charpath = (char*)   (void*)System::Runtime::InteropServices::Marshal::StringToHGlobalAnsi(path->Substring(0,2));
wchar_t* tpath = new wchar_t[MAX_DEVICE_LENGTH];

memset(tpath, '\0', MAX_DEVICE_LENGTH);

DWORD dwNum = MultiByteToWideChar (CP_ACP, 0, charpath, -1, NULL, 0);
MultiByteToWideChar (CP_ACP, 0, charpath, -1, tpath, dwNum );


dwResult = WNetGetConnection(
    tpath,
    szDeviceName, &MAX_DEVICE_LENGTH); 

System::String ^ str = gcnew System::String(szDeviceName);

str += path->Substring(2, path->Length-2);

delete(szDeviceName);
free(charpath); //This is where it assert-fails
delete(tpath);

return str;

Perhaps there is something basic in the area of ​​memory de-allocation, which I do not understand, but in any case, it is worth finding out. If this helps, if I skip this line, then tpath will remove the penalty, but if the charpath statement fails, then tpath will also fail.

+5
4

MSDN -

StringToHGlobalAnsi . , , FreeHGlobal. StringToHGlobalAnsi Marshal.PtrToStringAnsi.

, no delete/free, FreeHGlobal.

+8

szDeviceName tpath delete[] delete. [] , [] .

+5

MSDN, FreeHGlobal

+1

:

free(charpath);

charpath StringToHGlobalAnsi, FreeHGlobal. :

Marshal::FreeHGlobal(IntPtr(charpath));
+1

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