This patch fixes the issue related to delayed response
of the snmpd agent when monitors are used.

This patch is taken from the community for the following bug. 
snmpd: PATCH: 1918383: Fix DisMan monitoring of AgentX subagents
http://sourceforge.net/p/net-snmp/patches/897/
--- net-snmp-5.4.1.old/agent/mibgroup/utilities/iquery.c	2006-10-12 15:21:28.000000000 -0700
+++ net-snmp-5.4.1/agent/mibgroup/utilities/iquery.c	2013-07-09 14:39:34.856060200 -0700
@@ -159,6 +159,8 @@
             memdup( &(ss->community), secName, strlen(secName));
             ss->community_len = strlen(secName);
         }
+        ss->myvoid = netsnmp_check_outstanding_agent_requests;
+        ss->flags |= SNMP_FLAGS_RESP_CALLBACK | SNMP_FLAGS_DONT_PROBE;
     }
 #endif
 
--- net-snmp-5.4.1.old/include/net-snmp/library/snmp_api.h	2007-03-23 02:44:49.000000000 -0700
+++ net-snmp-5.4.1/include/net-snmp/library/snmp_api.h	2013-05-08 02:17:51.242309300 -0700
@@ -300,7 +300,10 @@
     void           *securityInfo;
 
     /**
-     * use as you want data 
+     * use as you want data
+     *
+     *     used by 'SNMP_FLAGS_RESP_CALLBACK' handling in the agent
+     * XXX: or should we add a new field into this structure? 
      */
     void           *myvoid;
 };
@@ -394,6 +397,7 @@
 
 #define SNMP_DETAIL_SIZE        512
 
+#define SNMP_FLAGS_RESP_CALLBACK   0x400      /* Additional callback on response */
 #define SNMP_FLAGS_USER_CREATED    0x200      /* USM user has been created */
 #define SNMP_FLAGS_DONT_PROBE      0x100      /* don't probe for an engineID */
 #define SNMP_FLAGS_STREAM_SOCKET   0x80
--- net-snmp-5.4.1.old/snmplib/snmp_client.c	2007-07-03 15:36:42.000000000 -0700
+++ net-snmp-5.4.1/snmplib/snmp_client.c	2013-07-09 14:48:09.041945100 -0700
@@ -1014,7 +1014,7 @@
         count = select(numfds, &fdset, 0, 0, tvp);
         if (count > 0) {
             snmp_read(&fdset);
-        } else
+        } else {
             switch (count) {
             case 0:
                 snmp_timeout();
@@ -1040,6 +1040,14 @@
                 state->status = STAT_ERROR;
                 state->waiting = 0;
             }
+        }
+
+        if ( ss->flags & SNMP_FLAGS_RESP_CALLBACK ) {
+            void (*cb)(void);
+            cb = ss->myvoid;
+            cb();        /* Used to invoke 'netsnmp_check_outstanding_agent_requests();'
+                            on internal AgentX queries.  */
+        }
     }
     *response = state->pdu;
     ss->callback = cbsav;