Difference between revisions of "Command Line Calling Order"

main()
   netsnmp_session session, *ss;
   netsnmp_pdu    *pdu;
   netsnmp_pdu    *response;
   netsnmp_variable_list *vars;

   // the only thing you can do before snmp_parse_args is call the netsnmp_ds_set_(bool|int|string) functions

   snmp_parse_args(argv, argc, &session, ...);   // accepts argv, argc, a session to initialize and optional additional arguments
       snmp_sess_init(session);
       getopt();                                 // and process
       init_snmp("snmpapp");                     // change to your app name if something special
           // ensure we're only called once
           // set the application name to "snmpapp" (or whatever was passed in).
           snmp_debug_init();                    // starts debugging output if requested
           netsnmp_container_init_list();
           init_callbacks();
           init_snmp_logging();                  // figures out if we're logging to stdout, stderr, file, syslog, ...
           snmp_init_statistics();
           register_mib_handlers();              // registers default mibs, mibdirs, etc .conf handlers
           register_default_handlers();          // registers all the other common (zillion) snmp.conf tokens
           init_snmpv3(type);                    // SNMPv3 and security module specific init
           init_snmp_alarm();
           init_snmp_enum(type);
           init_vacm();                          // access control

           read_premib_configs();                // reads in early bootstapping .conf tokens (setting mibs to load, dirs, etc)
           netsnmp_init_mib();                   // reads in MIBs requested to load either default or special

           read_configs();                       // reads in the rest of the normal configuration tokens              

       // setup special session params
       // like v3/USM keys

       session->peername = NEXT_ARGV_AFTER_OPTS

   
   SOCK_STARTUP;                                 // a win32 specific required macro

   ss = snmp_open(&session);
       // initialize appropriate transport using peername
       // adds the session to the internal "list"
 
   pdu = snmp_pdu_create(SNMP_MSG_(GET|SET|GETNEXT|...));
       // sets up default values in the PDU
   snmp_add_null_var(pdu, ...);                 // adding in variables you want to get/set
   snmp_pdu_add_variable(pdu, ...);             // OR: use this one to add complete variables

   status = snmp_sync_response(ss, pdu, &response);  // Note: pdu is "consumed" by this call; don't use it again!
       snmp_send(ss, pdu);
       snmp_select_info()                       // figures out which sockets to select on and needed timeout values
       select();
       snmp_read(sockets);                      // parses any received packets
       
   // results are in the response list, assuming no errors.  See the snmpget code for example error handling

   if (response)
     snmp_free_pdu(response);
   snmp_close(ss);
   SOCK_CLEANUP;