fix(control_supervisor): do not pipe child stdout into an unread pipe - #52
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Arcod7 wants to merge 1 commit into
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fix(control_supervisor): do not pipe child stdout into an unread pipe#52Arcod7 wants to merge 1 commit into
Arcod7 wants to merge 1 commit into
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Children were spawned with stdout=PIPE and stderr=STDOUT, but nothing ever drained them: the Popen handles are only used for poll() and termination. Once the 64 KB kernel pipe buffer filled, the child blocked in write() and never recovered. For ros2_control_node this is quiet and misleading. Its real-time update loop is a separate thread and keeps publishing /joint_states at the configured rate, so the robot looks connected, but the main thread runs the executor -- so every subscription and service callback stops. Trajectory commands on <controller>/joint_trajectory are never consumed and every /controller_manager service times out. Send child stdout/stderr to DEVNULL instead.
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Children were spawned with stdout=PIPE and stderr=STDOUT, but nothing ever
drained them: the Popen handles are only used for poll() and termination.
Once the 64 KB kernel pipe buffer filled, the child blocked in write() and
never recovered.
For ros2_control_node this is quiet and misleading. Its real-time update
loop runs on a separate thread and keeps publishing /joint_states, so the
robot looks connected -- but the main thread runs the executor, so every
subscription and service callback stops. Trajectory commands are never
consumed and every /controller_manager service times out.
Send child stdout/stderr to DEVNULL instead.
Predates #51 (spawner-lock serialization, ready marker) -- that PR touched
the same file but not these three Popen calls, so this is still live on
feat-pixi.