How To Programmatically Trigger a SNMP Trap

MORE INFORMATION

1. Modify Testdll.dll SNMP extension agent sample located in \Mssdk\Samples\Netds\Snmp\Testdll of the Platform SDK by replacing SnmpExtensionInit() entry point in file Testdll.c with the following code:

         BOOL WINAPI SnmpExtensionInit(
             IN  DWORD               dwTimeZeroReference,
             OUT HANDLE              *hPollForTrapEvent,
             OUT AsnObjectIdentifier *supportedView)
         {
             SECURITY_ATTRIBUTES sa;
             SECURITY_DESCRIPTOR sd;
   
             sa.nLength = sizeof(SECURITY_ATTRIBUTES);
             sa.bInheritHandle = TRUE;
             sa.lpSecurityDescriptor = &sd;
   
             if(!InitializeSecurityDescriptor(&sd,
                                              SECURITY_DESCRIPTOR_REVISION))
                 return FALSE;   // Handle errors.
   
             // Add a NULL DACL to the security descriptor.
             if(!SetSecurityDescriptorDacl(&sd, TRUE, (PACL)NULL, FALSE))
                 return FALSE;   // Handle errors.
   
             // Record the time reference provided by the Extendible Agent.
   
             dwTimeZero = dwTimeZeroReference;
   
   
             // Create a named Event that will be used to communicate the
             // occurrence of traps to the Extendible Agent. The Extension
             // Agent will assert this Event when a trap has occurred. This
             // is explained later.
   
             // A named event is created with a null DACL such that other
             // processes are able to signal this Event as this Extension
             // agent does.
   
           if ((*hPollForTrapEvent =
                CreateEvent(&sa, FALSE, FALSE, TEXT("_MyTrapEvent"))) == NULL)
             {
                 // Indicate error?, be sure that NULL is returned to
                 // Extendible Agent.
             }
   
             // Indicate the MIB view supported by this Extension Agent, an
             // object identifier representing the sub root of the MIB that
             // is supported.
   
             *supportedView = MIB_OidPrefix; // NOTE!  structure copy
   
   
             // Record the trap Event. This example Extension Agent
             // simulates traps by generating a trap after every given number
             // of processed requests.
   
             hSimulateTrap = *hPollForTrapEvent;
   
   
             // Indicate that Extension Agent initialization was successful.
   
             return TRUE;
   
         } // end SnmpExtensionInit().
   						

2. You can use the following small program to test the trigger of trap event:

         #include <windows.h>
         #include <stdio.h>
   
         void main(void)
         {
             HANDLE hTrapEvent;
             char c;
   
             hTrapEvent = OpenEvent(EVENT_MODIFY_STATE, FALSE,
                                    TEXT("_MyTrapEvent"));
             if (hTrapEvent == NULL)
             {
                 printf(TEXT("Can't open the event _MyTrapEvent\n"));
                 return;
             }
             printf(TEXT("Hit t [enter] to trigger the sending of trap: \n"));
             while (1)
             {
                 scanf("%c", &c);
                 if (c == 't' || c == 'T')
                     SetEvent(hTrapEvent);
             }
         }