gtestdbus: Flush stdout and stderr before forking a monitor process
This is a workaround for the fact that forking without execing is not
easy to do correctly, and GTestDBus doesn’t do it correctly. However,
GTestDBus is de-facto deprecated and so putting any more effort in is
a waste.
This fixes an issue where a test would print duplicate output when
outputting to a fully-buffered FD, such as a pipe. This is because the
buffer is non-empty before the fork(), and ends up duplicated in the
parent and child processes, both of which later flush the duplicated
buffer contents.
Diagnosed and fix suggested by Simon McVittie.
Signed-off-by: Philip Withnall pwithnall@endlessos.org
Fixes: #2322 (closed)
Closes #2322 (closed)