I had a issue with process_create/3 using the latest SWI-Prolog 8.1.19
It seemed as if stderr(std) was sent to stdout(pipe(In)) and here is how I worked around
https://github.com/josd/eye/commit/c50bbca8cde9fd05f907292afac6e69598df5ead#diff-4424d26c862cb058208d3758ae06b8b9 which is of course not ideal
Thanks for keeping up the good thing with SWI-Prolog
and all the best wishes for 2020 !