if DISTDIR points to somewhere on VFAT partition, then following would be good to leave on PORTDIR or option to give them own path: .locks csv-src svn-src am I wrong?
The $DISTDIR/.locks is possible to change but csv-src and svn-src belong to cvs.eclass and subversion.eclass (separate from portage), so portage doesn't control those. Can't you just use FEATURES="-distlocks" with vfat?
oh my bad, thought portage takes care for cvs and svn too.
I just noticed that make.conf.example says portage will use PORTAGE_TMPFS for file locking, but it doesn't really do that. The danger with making the DISTFILES locking configurable is that all portage instances that share it must use the same exact locking directory, or else it becomes useless.
Don't like this idea at all.