The CIRC event's Purpose spec is reused for CIRC_MINOR events... https://gitweb.torproject.org/torspec.git/blob/HEAD:/control-spec.txt#l1291 Looks like the later can emit a MEASURE_TIMEOUT purpose which is undocumented (newlines added by me)... ``` 650 CIRC_MINOR 7 PURPOSE_CHANGED $67B2BDA4264D8A189D9270E28B1D30A262838243~europa1 BUILD_FLAGS=IS_INTERNAL,NEED_CAPACITY PURPOSE=MEASURE_TIMEOUT TIME_CREATED=2012-12-03T16:45:33.409602 OLD_PURPOSE=TESTING ```