How do I convert a char variable to a BSTR in C?

See more:

C

COM

I have a legacy program written in C that I am having to add calls to a COM object. The problem I am having is passing the data to the functions in the COM module. I can pass literals to the module but how can I convert the variables to BSTR?

Example with literals:

BSTR baseUrl = SysAllocString(L"www.google.com");
BSTR sessionName = SysAllocString(L"");
VARIANT_BOOL returnVal;
result = viewer->pVtbl->launchSession(viewer, baseUrl, sessionName, &returnVal);
if (result != S_OK)
{
    printf("COM call to WebViewer.launchSession failed\n");
    SysFreeString(baseUrl);
    SysFreeString(sessionName);
    return 1;
}

Instead of hard coding "www.google.com" I need to use variable defined as char [215].

What I have tried:

I found

_com_util::ConvertStringToBSTR(lpszText);

but I can't figure out how to use it in C. All the examples are for C++.