This appears to be harmless, except for Python 2.6 on Linux/Travis,
where for some reason (some stdlib change?) simply opening the TTY is
insufficient.
The 'versioner.c' dodging check added in 0ef23d86 was wrong, since the
check occurred on the host machine, when the fix actually needs to apply
to the Darwin target.
Fixes ability to target OS X from a Red Hat controller, manifesting as
an error like:
D mitogen: mitogen.parent.TtyLogStream('local.2472'): 'python(mitogen:dmw@localhost.localdomain:2449): realpath couldn\'t resolve "/usr/bin/python(mitogen:dmw@localhost.localdomain:2449)"'
The "realpath couldn't resolve" error comes from versioner.c:
https://opensource.apple.com/source/perl/perl-104/versioner/versioner.c
It's possible for a message to arrive after .add_handler() but before
Latch construction.
This is papering over a bigger problem with service pool instantiation.
https://travis-ci.org/dw/mitogen/jobs/390409832#L2901
TASK [Spin up a few interpreters] **********************************************
changed: [target] => (item=1)
ERROR! [pid 5355] 14:47:50.224945 E mitogen.ctx.ssh.localhost:2201.sudo.mitogen__user2: mitogen: Router(Broker(0x7f1e93911450))._invoke(Message(19100, 19095, 19095, 110, 1005, '\x80\x02U\x1fmitogen.service.PushFileServiceq\x01U\x11store_and_f'..8955)): <bound method Receiver._on_receive of Receiver(Router(Broker(0x7f1e93911450)), 110)> crashed
Traceback (most recent call last):
File "<stdin>", line 1471, in _invoke
File "<stdin>", line 491, in _on_receive
AttributeError: 'Receiver' object has no attribute '_latch'
See source comment. This behaviour always existed, but it now seems to
be triggered since we started draining the master side input buffer,
which someone was prolonging the life of the PTY.
David Wilson