This reverts commit 3c87f01b18.
This commit introduced two regressions;
- spurious "Unsupported signal: <nil>. Discarding."
- docker start --attach hanging if the container does not
have a TTY attached
Reverting for now, while we dug deeper into what's causing
the regression.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>