`git-annex-shell p2pstdio` hides error messages that were transported over
ssh to display to the user before. For example, diskreserve problems or IO
errors. --[[Joey]]

git-annex discards stderr from the command because old
versions of git-annex-shell don't support the command and error out.

Simply letting stderr through seems like the best solution though,
if a way can be found to do it.
Otherwise, all errors would have to be trapped (easy), and all stderr
output also trapped (hard!), to be sent over the protocol using ERROR.
And, there'd be a problem with sending messages atomically; if a message is
being sent and an exception is thrown, that message needs to somehow be
ended before an ERROR message can be sent.

Hmm, it negotiates the protocol version after opening the connection.
Any error at that point would make it not use the p2p protocol, 
so can be excluded. Then, after version negotiation is complete, it
could start displaying stderr.

> [[fixed|done]] --[[Joey]]
