How to extract/embed exif thumbnails

[Harry]

Using C Core, I cannot figure out how to extract and embed the exif thumbnail attribute in an image.

I have come as far as figuring out that I need to use the attributes named "EXIF:Thumbnail*", such as ThumbnailData, in Get/SetImageAttribute().

However, looking at attribute.c, I count 37 attributes named "Thumbnail*", which is pretty intimidating.

Could somebody furnish a code fragment, or point me to where I can find an example coded in any programming language (as long as it uses C Core)?