export: do not print '<fdopen>' as an output filename...
export: do not print '<fdopen>' as an output filename
Because makefileobj() duplicates or wraps stdout, "fp != sys.stdout" didn't
work correctly. Python doc states that special file objects are named in the
form '<...>', and absolute filenames should never start with '<', we can
ignore names start with '<'. We can't test fp.fileno() because fp may be a
command-server channel.
https://docs.python.org/2.7/library/stdtypes.html#file.name
In the test output, "exporting patch:" line is printed after patch content.
This is caused by fdopen() and will be fixed by the subsequent patch.