HMGetFont
short *font; the global font number
You can use the HMGetFont function to get information about the font that is currently used to display text (that is, Pascal strings and
strings from 'STR#' and 'STR ' resources) in help balloons. This does
not apply to text in 'PICT' or styled text resources, or to text in
handles to either of these resources.
font is the global font number used to display text in help balloons
noErr (0) No error
memFullErr (-108) Not enough room in heap zone
Warning: If your application changes the font name or size, the change affects
all applications and software that display help balloons