Closing the original stdout is how we signal to a larger compatibility
tool (in practice pressure-vessel) that either we are ready, or we have
crashed: when every process that held the write end open has closed it,
the compatibility tool sees EOF on the pipe. If the FEXServer inherits
stdout and holds it open, then that state will never be reached.
steamrt/tasks#870
Signed-off-by: Simon McVittie <smcv@collabora.com>
Always enables FEXServer log thread when built for Steam so that clients
can be controlled with `STEAM_FEX_LOG=1`. FEX logs will then always go
to FEXServer and those can get directed to wherever pressure-vessel
chooses.
This is fairly simple. Needs to be installed alongside FEXServer, so
that it can start it in a portable config.
- Starts a FEXServer
- Tells pressure-vessel when FEXServer is ready
- Keeps FEXServer alive with the `watch_fd` as long as the process lives
- Listens for pressure-vessel to be shutting down
- Exits once pressure-vessel exits, also letting FEXServer shutdown if
no FEX instances are alive.
Ryan Houdek