Function wxd_PropertyGrid_GetValueAsString 

pub unsafe extern "C" fn wxd_PropertyGrid_GetValueAsString(
    self_: *const wxd_PropertyGrid_t,
    name: *const c_char,
    out: *mut c_char,
    out_len: usize,
) -> c_int

Get the displayed value as UTF-8 using the standard two-call buffer API.