The library assumes that everyone has a gateway to register with. There are use cases where direct peer-to-peer SIP calls are wanted, which baresip supports, and thus the forced registration causes problems.
7a692100174b94445865a7f90abbb825bc9d3d94 should fix most of this. Introduces a new Identity class, and that class allows setting all the flags you want on the SIP identifier, including regint=0
The library assumes that everyone has a gateway to register with. There are use cases where direct peer-to-peer SIP calls are wanted, which baresip supports, and thus the forced registration causes problems.