sofia-sip-doc 1.12.11+20110422.1-2.1+deb10u3ubuntu0.20.04.1 (riscv64 binary) in ubuntu focal

 Sofia-SIP is an open-source SIP User-Agent library, compliant
 with the IETF RFC3261 specification. It can be used as
 a building block for SIP client software for uses such as VoIP,
 IM, and many other real-time and person-to-person communication
 services.
 .
 This package provides the library reference documentation.