Install libosip2-dev by entering the following commands in the terminal:
sudo apt update sudo apt install libosip2-dev
development files for the SIP library
libosip2 header files and static libraries to assist in development of programs wishing to use SIP. . The oSIP library is written in C, is thread safe and has no dependencies except the standard C library. . oSIP could be used to implement an IP soft-phone as well as embedded SIP software. oSIP is not limited to endpoint agents implementations and can also be used to implement SIP proxies or registration services. . oSIP currently provides an API for the SIP message parser, SDP message parser, and library to handle "SIP transactions" as defined by the SIP standards (RFC3261).