char *text;
int ptrpos;

int max_char_width = /*you can figure out how to do this */;

if (strlen(text) <= max_char_width) return();



while ( strlen(text) > max_char_width)
{
        ptrpos=max_char_width;
        while( ( ptrpos > 0 ) && (text[ptrpos] != ' ')) ptrpos-- ;

        /* draw text up to ptrpos here*/

        text += ptrpos;
}