How does setup.exe figure out what to install by default?

[Jonathan Kamens]

I'm trying to figure out how setup.exe decides which packages should
be installed by default.  My best guess was that "Base" categories are
installed by default, but I couldn't find any evidence of that in the
source code in winsup/cinstall (I looked at every instance of the word
"base", and unless I missed it, none of them were the one that would
key this functionality).  I found code which seems to suggest that
"Required" or "Misc" packages are installed by default, but I don't
see anything designated "Required" or "Misc" in setup.ini, so I don't
know how those bits would get set on a package (and I suspect that's a
red herring because I'm not understanding it properly anyway).

Somebody wanna give me a hint? :-)

Also, I was trying to learn something from the setup.log and
setup.log.full that get generated during an install, and there was
something about this that puzzled me very early on too -- I see
setup.exe's command line parameters logged in both log files, and yet
I don't see where that logging happens -- it doesn't seem like WinMain
passes command_line to anything, and the string "Command line
parameters", which appears in the log file, doesn't seem to appear
anywhere in winsup/cinstall.

Is there some Windows magic that I'm missing here?

Thanks,

  Jonathan Kamens