[[!comment format=mdwn
 username="joey"
 subject="""comment 1"""
 date="2017-02-15T18:04:29Z"
 content="""
I am able to reproduce this, and it only happens when the remote being
checked is a ssh remote, not a local directory.

So, presumably something in the verification that the remote has the
content is sometimes consuming the rest of stdin.

The different numbers processed each time are probably due to buffering. If
the command feeding the list of keys takes a while to print them all, and
parts of its output are being thrown away, then that would explain the
different numbers processed.

Using ssh -n to run git-annex-shell checkpresentkey avoids the problem.

This could also impact git-annex being used in some script, when the script
is intended to consume stdin, but git-annex runs ssh, which consumes it
instead. Other commands like `git annex drop` could be affected
too in such situations.

I've put in a comprehensive fix to all of git-annex's calls to ssh
that don't provide some other stdin.
"""]]