libcoap  4.1.2
Here is a list of all modules:
 Rate ControlThe transmission parameters for CoAP rate control ("Congestion Control" in stream-oriented protocols) are defined in
 Asynchronous MessagingStructure for managing asynchronous state of CoAP resources
 Block Transfer
 Clock HandlingDefault implementation of internal clock
 Option Filters
 Pseudo Random Numbers
 Resource observation
 URI Parsing FunctionsCoAP PDUs contain normalized URIs with their path and query split into multiple segments