Pertaining exactly to the topic of this question which asks about the various auxiliary files produced by tex and friends, I'd like to ask specifically about the
.fof file extension. If the main file is
main.fof is created.
I am asking here because I thought that this was a side-effect file that shall be automatically created and therefore ignored this in my VCS. However, after cloning the repository in another computer,
luatex complained that this
fof file was missing.
What is an
fof file, and what information does it convey to the compiler?