How to make database build threaded?

[Franco Martelli]

Hi everybody,
I'm the author of a small C++11 program called XDGSearch. The source
code is hosted on Github, for a quick overview you can visit this link
https://github.com/frank67/XDGSearch/blob/master/README.md
I'm writing to the mailing list because I'd like to make the database
build process splitted in more thread. Is it possible? If you are a C++
programmer you can take a look at the populateDB() function at this link
https://github.com/frank67/XDGSearch/blob/597380bfd7de94857cef08c95e5e31392807a7cb/indexer.cpp#L85
which is the heart of the databases creation process.
I'd be also happy if I find somebody that want to be involved in the
XDGSearch development :)
Thanks in advance for any answer, best regards

-- 
Franco Martelli