Added runtime/spawn_subprocess.py. Force use posix spawn instead of fork, with API similar to subprocess. Using fork in runtime is incompatible with Xenomai, because memory is locked and this can lead to out of memory error.
#!/bin/sh
LC_ALL=ru_RU.utf-8
export DISPLAY=:42
Xvfb $DISPLAY -screen 0 1280x1024x24 &
sleep 1
ret=0
DELAY=400
KILL_DELAY=$(($DELAY + 30))
timeout -k $KILL_DELAY $DELAY pytest --timeout=10 ./tests/tools
ret=$?
pkill -9 Xvfb
exit $ret