Monitor::CheckAction() handled the RELOAD action (zmu --reload, or a script
setting it through ZoneMinder::Memory) by calling Reload() in place. That
runs on zmc's capture thread, and Monitor::Load() rewrites settings such as
label_format, orientation and the image sizes while the decoder and analysis
threads read them unlocked.
SIGHUP already reloads safely: zmc leaves its capture loop, Close()s and
disconnect()s each monitor, which stops those threads, then Reload()s and
reconnects. Have the action set zm_reload, as the SIGHUP handler does, so
both take that path.
zmc reloads every monitor it runs this way, not only the one the action was
sent to; zmc normally runs one.
Tested live on 1.38 with zmu --reload against a running zmc: the event closes,
the same process reloads and reconnects, capture resumes and a new event
opens.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
