autotest/autotest — pull request #73 by lmr (2011-11-16 01:46:58+00:00)
Title: client: autotestd_monitor - Eliminate dependency on tail

People using autotest in systems with busybox might have
trouble with the fact that busybox's tail doesn't support
any of the required options. Given that tail's functionality
can be emulated using a few lines of python, let's go
ahead and do it.

The idea is to replace tail subprocesses watching the stdout
file to sys.stdout and watching the stderr file to
sys.stderr with threads that keep reading lines from those
files and writing them to the respective streams.

This code was lightly tested (only run autoserv in some
target machines), so quite a bit of testing should go
in the event people are OK with it. After all, the
reasoning of avoiding calling out to external programs
if we can do the same with a reasonable amount of standard
python is sound, besides reducing client requirements.

Signed-off-by: Lucas Meneghel Rodrigues