wcstombs is not working

[C++ Programming]

hi all,

i am using wcstombs function to convert my const wchar* value to char*.... but its showing ?? marks instead of unicode characters..

i tried using widechartomultibyte like this... [(WideCharToMultiByte(CP_ACP, 0, Text, 0, Chartext, nSize, NULL, NULL); where int nSize =0;] but its also not converting the value....

can anyone help me where am i going wrong...

Thanks,
Rakesh.