Edit EXIF data using external library

I would like to know if it's possible to use libraw to edit exif related metadata, by passing data structure to some other library like libexif or similar.

I'm interested in changing Lens related information (name, id, type...), aperture and focal length inside a CR2 file.
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I had a look to the documentation and found that libraw parse metadata and save the above info in libraw_lensinfo_t and libraw_makernotes_lens_t; if I understand right they are read-only but is possible to install hook for EXIF data when parsing file.

My idea was to open a file, extract datas using libraw to pass pointer to libexif and then finally write back to disk.

Is this possible with the current code?
Can someone point me to what function should I use? Especially how to save modified picture.

Do to the need to use this in an embedded system (some posix like api), is recommended to use LibRaw::open_buffer() to open file or better to use directly LibRaw::open_datastream()?

Any suggested approach is welcome.
Thank you

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Is this possible with the

Is this possible with the current code?

I do not know. Please try and let us know

is recommended to use LibRaw::open_buffer() to open file or better to use directly LibRaw::open_datastream()
Both ways should work.

-- Alex Tutubalin