SCTP provides the application writer with two different interface styles: the one-to-one style, mostly compatible with existing TCP applications to ease migration to SCTP, and the one-to-many style, allowing access to all of SCTP's features. The sctp_peeloff function provides a method of extracting an association from one style to the other. SCTP also provides numerous notifications of transport events to which an application may wish to subscribe. These events can aid an application in better managing the associations it maintains.
Since SCTP is multihomed, not all the standard sockets functions introduced in Chapter 4 are adequate. Functions like sctp_bindx, sctp_connectx, sctp_getladdrs, and sctp_getpaddrs provide methods to better control and examine the multiple addresses that can make up an SCTP association. Utility functions such as sctp_sendmsg and sctp_recvmsg can simplify the use of these advanced features. We will explore many of the concepts introduced in this chapter in more detail through examples in Chapters 10 and 23.