Swap stdout/stderr -- debug messages then go to stderr, and yaml data to stdout

s3tests/common/__init__.py

@@ -4,6 +4,7 @@ import itertools
 import os
 import random
 import string
+import sys
 import yaml
 
 s3 = bunch.Bunch()
@@ -13,6 +14,10 @@ prefix = ''
 # For those scripts that use a context, these are pretty univerally needed.
 context = bunch.Bunch(
     bucket = None,
+
+    # Save stdout/stderr in case they get fudged with.
+    real_stdout = sys.stdout,
+    real_stderr = sys.stderr,
 )
 
 bucket_counter = itertools.count(1)

s3tests/common/results.py

@@ -93,7 +93,7 @@ class ResultsLogger(gevent.Greenlet):
     """ A quick little greenlet to always run and dump results. """
     def __init__(self):
         gevent.Greenlet.__init__(self)
-        self.outfile = sys.stderr
+        self.outfile = context.real_stdout
 
     def _run(self):
         while True:

s3tests/roundtrip.py

@@ -10,6 +10,7 @@ import random
 import realistic
 import time
 import traceback
+import sys
 
 import common
 from common import context, config
@@ -86,6 +87,7 @@ def _main():
 
 
 def main():
+    sys.stdout = sys.stderr # Original steam already saved by common
     common.setup()
     setup()