debugcommands: move away from line buffered output on binary stream...
debugcommands: move away from line buffered output on binary stream
Line buffering on binary file objects is apparently undefined behavior
in Python and emits a RuntimeWarning on Python 3.8. See
https://bugs.python.org/issue32236.
This commit changes the I/O logging file descriptor from line
buffered to unbuffered to work around this. I'm no fan of
unbuffered I/O for performance reasons. But I don't think it
is an issue here given the nature of the code.
With this change, test-ssh-proto.t now passes on Python 3.8.
Differential Revision:
https://phab.mercurial-scm.org/D7948
