version 1 .
# Definitions for non-modem-hardware-specific telephony interactions.

ModemPresent = <modem @type symbol @devicePath string @dataspace #:any> .

Address = <address @numberType NumberType @number string> .
NumberType = =unknown / =international / =national / =gsm0338 .

# Assertion. Describes an ongoing call.
ActiveCall = <call-state @callId CallId @direction CallDirection @type CallType @peer Address @state CallState> .
CallId = int .
CallDirection = =mo / =mt .
CallType = =voice / =data / =fax .
CallState = =hold / =original / =connect / =incoming / =waiting / =end / =alerting .

# Message. Triggers call answering.
AnswerCall = <answer-call @callId int> .

# Message. Triggers call rejection or disconnection.
DisconnectCall = <disconnect-call @callId CallIdSelector @cause ReleaseCause> .
CallIdSelector = @specificCall int / @allCalls =all .
ReleaseCause =
/ =unassignedNumber
/ =normal
/ =busy
/ =noUserResponding
/ =callRejected
/ =destinationOutOfOrder
/ =normalUnspecified
/ =incompatibleDestination
.

# Message. Starts an outgoing call.
PlaceCall = <place-call @devicePath string @peer Address> .

# Assertion. Some call is active - be it alerting, connected, ringing, etc.
CallInProgress = <call-in-progress> .

# Assertion. An incoming call is signalling the user, asking for a decision about answer/reject/ignore.
PhoneRinging = <phone-ringing> .

# Assertion. A remote party's phone should be ringing.
PeerRinging = <peer-ringing> .

# Message. An incoming SMS has been received.
SmsDelivery = <sms-delivery @smsc Address @peer Address @timestamp time.Stamp @body string> .

# Assertion. An outgoing SMS should be transmitted.
SmsTransmission = <sms-transmission @smsc Address @peer Address @body string @continuation #:=ok > .

# Assertion. Enable speakerphone mode, if available.
Speakerphone = <speakerphone> .