3.7. SIGNAL

Sent from the client to the server. The syntax is:

"SIGNAL" SP Signal CRLF

Signal = "RELOAD" / "SHUTDOWN" / "DUMP" / "DEBUG" / "HALT" / "HUP" / "INT" / "USR1" / "USR2" / "TERM" / "NEWNYM" / "CLEARDNSCACHE" / "HEARTBEAT" / "ACTIVE" / "DORMANT"

The meaning of the signals are:

• RELOAD -- Reload: reload config items.
• SHUTDOWN -- Controlled shutdown: if server is an OP, exit immediately. If it's an OR, close listeners and exit after ShutdownWaitLength seconds.
• DUMP -- Dump stats: log information about open connections and circuits.
• DEBUG -- Debug: switch all open logs to loglevel debug.
• HALT -- Immediate shutdown: clean up and exit now.
• CLEARDNSCACHE -- Forget the client-side cached IPs for all hostnames.
• NEWNYM -- Switch to clean circuits, so new application requests don't share any circuits with old ones. Also clears the client-side DNS cache. (Tor MAY rate-limit its response to this signal.)
• HEARTBEAT -- Make Tor dump an unscheduled Heartbeat message to log.
• DORMANT -- Tell Tor to become "dormant". A dormant Tor will try to avoid CPU and network usage until it receives user-initiated network request. (Don't use this on relays or hidden services yet!)
• ACTIVE -- Tell Tor to stop being "dormant", as if it had received a user-initiated network request.

The server responds with "250 OK" if the signal is recognized (or simply closes the socket if it was asked to close immediately), or "552 Unrecognized signal" if the signal is unrecognized.

Note that not all of these signals have POSIX signal equivalents. The ones that do are as below. You may also use these POSIX names for the signal that have them.

• RELOAD: HUP
• SHUTDOWN: INT
• HALT: TERM
• DUMP: USR1
• DEBUG: USR2

[SIGNAL DORMANT and SIGNAL ACTIVE were added in 0.4.0.1-alpha.]