// Make sure the HKCR\Component Categories\{..catid...}
// key is registered.
CATEGORYINFO catinfo;
catinfo.catid = catid;
catinfo.lcid = 0x0409 ; // english
// Make sure the provided description is not too long.
// Only copy the first 127 characters if it is.
int len = wcslen(catDescription);
if (len>127)
len = 127;
wcsncpy(catinfo.szDescription, catDescription, len);
// Make sure the description is null terminated.
catinfo.szDescription[len] = ''\0'';