A recent email correspondent asked:

How can I decompress the huffman-compressed file attachments in Notes?

The answer is: you can’t. The Notes C API provides no facility to do this, and Lotus (or IBM or Iris, or whatever they should be called now) has never documented the compression algorithm. The only way to decompress these attachments is to use the C API functions NSFNoteExtractFile or NSFNoteExtractFileExt. Both of these functions take a filename, and the decompressed data is written to the file.

Of course, this is really stupid. For one thing, when writing high-throughput software, the last thing you want to do is write more data to disk. If I need to process the data in a file attachment, I want a way to read the data into memory, and writing it to a temp file just to read it back in so I can do whatever to it, is just wasteful.

Of course, IBM (or Lotus or Iris, or whatever) has functions to do the decompression, they just haven’t been exposed as part of the C API.

I used to work at Iris (or Lotus, or whatever), but I don’t know how the compression works, or what the functions are to do the decompression. I’d like to have access to them as well, but I’m in the same boat as everyone else.