[This is preliminary documentation and subject to change.]
The WinSNMP manager application must call the SnmpStartup function successfully before it calls any other WinSNMP function. The SnmpStartup function enables the Microsoft WinSNMP implementation to perform initialization procedures. The function also returns to the application the version of the WinSNMP Manager API that the implementation supports, the level of SNMP communications it supports, and the implementation's default translation and retransmission modes.
The WinSNMP manager application must call the SnmpCleanup function when the application no longer requires the implementation's services. Even though SnmpCleanup enables the implementation to deallocate all resources allocated to the application, it is recommended that the application first call the SnmpClose function once for each open WinSNMP session, to maximize the implementation's performance. The WinSNMP manager application must call SnmpCleanup as the last WinSNMP function before it terminates.