What im trying to do is send a string from the find file structure to a listbox. heres the code I am using

Code:
SendMessage(listbox,LB_ADDSTRING,NULL, fd.cFileName);
the error I get is:
cannot convert parameter 4 from 'char [260]' to 'long'
This conversion requires a reinterpret_cast, a C-style cast or function-style cast

Any help is greatly appreciated! Thanks