[aayushshah15]

The idle loop read the activity marker's mtime with GNU stat -c %Y. macOS ships BSD stat, which has no -c. Under the step's bash -e, the first check after blacksmith testbox run touches ~/.testbox-last-activity would exit the job and kill a macOS Testbox.

FILE_MTIME=$(stat -c %Y ~/.testbox-last-activity 2>/dev/null || stat -f %m ~/.testbox-last-activity)

ss is also missing on macOS. That check sits in an if condition, so it falls through to the marker file and doesn't abort the step. Reported in Pylon #15905.

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macOS idle loop survives marker read

With BSD-style stat and no ss, the old step dies with exit 1 at the first marker read. The new step reads the marker mtime through stat -f %m, keeps looping, and later shuts down normally on idle timeout with exit 0.

_Merge-base

_{This PR 0da87a25}

Also checked · 2 match

Same epoch mtime on Linux GNU stat
Missing ss falls through, no exit

_{Proof on 0da87a25}

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