Crash after failing to write to the state file
Approximately once per day since installing 0.2.2.20-alpha, Tor has crashed shortly after (but not immediately after) failing to write the state file:
Dec 29 21:26:49.373 [Warning] Error replacing "C:\Users\xxx\AppData\Roaming\tor\state": Permission denied
Dec 29 21:26:49.375 [Warning] Unable to write state to file "C:\Users\xxx\AppData\Roaming\tor\state"
Dec 29 21:26:49.484 [Info] circuit_finish_handshake(): Finished building circuit hop:
Dec 29 21:26:49.489 [Info] internal circ xxx
Dec 29 21:26:49.493 [Info] circuit_build_times_disabled(): CircuitBuildTime learning is disabled. Consensus=0, Config=0, AuthDir=0, StateFile=1
Dec 29 21:26:49.498 [Info] circuit_send_next_onion_skin(): circuit built!
Dec 29 21:26:49.503 [Info] connection_ap_handshake_attach_circuit(): Intro circ 38291 present and awaiting ack (rend 38292). Stalling. (stream 50 sec old)
Dec 29 21:26:49.507 [Info] circuit_finish_handshake(): Finished building circuit hop:
Dec 29 21:26:49.510 [Info] internal circ xxx # different circuit from the first time
Dec 29 21:26:49.514 [Info] circuit_build_times_disabled(): CircuitBuildTime learning is disabled. Consensus=0, Config=0, AuthDir=0, StateFile=1
Dec 29 21:26:49.519 [Info] circuit_send_next_onion_skin(): circuit built!
Dec 29 21:26:49.523 [Info] connection_ap_handshake_attach_circuit(): Intro circ 38291 present and awaiting ack (rend 38292). Stalling. (stream 50 sec old)
# Crashed
I suspect that this is related to the CircuitBuildTime being disabled, as that seems to be the only meaningful side effect of a state file write failure. I don't know of any reason for Tor to periodically get 'Permission denied' when trying to replace the state file.