Several functions, data structures, and constants are defined in the snmpmgr.h file in the /usr/include directory. To build, send, and receive an SNMP message, your SNMP manager needs to call certain functions. After each call to one of these functions, your SNMP manager should verify that a successful return code, SNMP_MGR_RC_OK, was passed back. If an error occurs during the function call, an invalid return code is passed back. In addition to the error code, your SNMP manager API log file contains helpful information about the specific cause of the error. See Debugging the SNMP manager API for information about using the debugging features.

By calling the following functions from your SNMP manager, you build the data structures necessary to send an SNMP message to an SNMP agent or subagent. The packet your SNMP manager receives as a response from the target agent can then be decoded and parsed with the defined set of helper functions. These helper functions provide your SNMP manager the ability to extract those same data structures that were used to create the outgoing packet.