Had everything available, just didn't combine the progress meter with the
other places progress is sent to update it. (And to a remote repo already
did show progress.)
Most special remotes should already display progress meters with -J,
same as without it. One exception to this is the web, since it relies on
wget/curl progress display without -J. Still todo..
This was in the cabal file earlier, and was removed because it broke the
android cross build. Moving to the git-annex target of the Makefile
will make it be used for Debian packages etc but not android cross builds
or make fast or when users build with cabal.
There's a potential race, but it's detected and just results in the other
process failing to take the side lock, so possibly retrying one second
later on. The race window is quite narrow so the extra delay is minor.
Left the side lock files mode 666 because an interruption can leave a side
lock file created by another user for a shared repository. When this
happens, the non-owning user can't delete it (+t) but can still lock it,
and so the code falls back to acting as it did before this commit.
This is less portable, since currently sidelocks rely on /dev/shm.
But, I've seen crazy lustre inconsistencies that make me not trust the
link() method at all, so what can you do.
I have a strace taken on a lustre filesystem on which link() returned 0,
but didn't actually succeed, since the file already existed.
One of the linux man pages recommended using link followed by checking like
this. I was reading it yesterday, but cannot find it now.
