The sctp_bindx() function manages addresses on an SCTP socket. If the sock parameter is an IPv4 socket, the addresses passed to the sctp_bindx() function must be IPv4 addresses. If the sock parameter is an IPv6 socket, the addresses passed to the sctp_bindx() function can be either IPv4 or IPv6 addresses. When the address that is passed to the sctp_bindx() function is INADDR_ANY or IN6ADDR_ANY, the socket binds to all available addresses. Bind the SCTP endpoint with the bind(3SOCKET)
The value of the *addrs parameter is a pointer to an array of one or more socket addresses. Each address is contained in its appropriate structure. If the addresses are IPv4 addresses, they are contained in either sockaddr_in structures or sockaddr_in6 structures. If the addresses are IPv6 addresses, they are contained in sockaddr_in6 structures. The address type's family distinguishes the address length. The caller specifies the number of addresses in the array with the addrcnt parameter.
The sctp_bindx() function returns 0 on success. The sctp_bindx() function returns -1 on failure and sets the value of errno to the appropriate error code.
If the same port is not given for each socket address, the sctp_bindx() function fails and sets the value of errno to EINVAL.
The flags parameter is formed from performing the bitwise OR operation on zero or more of the following currently defined flags:
SCTP_BINDX_ADD_ADDR directs SCTP to add the given addresses to the association. SCTP_BINDX_REM_ADDR directs SCTP to remove the given addresses from the association. The two flags are mutually exclusive. If both are given, the sctp_bindx() fails and sets the value of errno to EINVAL.
A caller may not remove all addresses from an association. The sctp_bindx() function rejects such an attempt by failing and setting the value of errno to EINVAL. An application can use sctp_bindx(SCTP_BINDX_ADD_ADDR) to associate additional addresses with an endpoint after calling the bind() function. An application can use sctp_bindx(SCTP_BINDX_REM_ADDR) to remove addresses associated with a listening socket. After using sctp_bindx(SCTP_BINDX_REM_ADDR) to remove addresses, accepting new associations will not reassociate the removed address. If the endpoint supports dynamic address, using SCTP_BINDX_REM_ADDR or SCTP_BINDX_ADD_ADDR sends a message to the peer to change the peer's address lists. Adding and removing addresses from a connected association is optional functionality. Implementations that do not support this functionality return EOPNOTSUPP.
If the address family is not AF_INET or AF_INET6, the sctp_bindx() function fails and returns EAFNOSUPPORT. If the file descriptor passed to the sctp_bindx() in the sock parameter is invalid, the sctp_bindx() function fails and returns EBADF.