[Asterisk-Users] Detecting if a call is active on chan_sip before trying INVITE? (was Sip question - allow only 1 incoming call to sip phone)

Disable the call waiting feature in the phone, so it will signal 486 - Busy here to additionally incoming calls. Is it possible to test if a call to SIP/xxx is in place before dialling out? This could help a lot to centralize administation of whether or not to use call waiting instead of

Re: [Asterisk-Users] Detecting if a call is active on chan_sip before trying INVITE? (was Sip question - allow only 1 incoming call to sip phone)

Roy Sigurd Karlsbakk wrote: Is it possible to test if a call to SIP/xxx is in place before dialling out? This could help a lot to centralize administation of whether or not to use call waiting instead of configuring the ATAs. app_groupcount can be used to provide call counting in any fashion you