使用net-snmp API编程

gcc -o redweb redweb.c  -lkstat -lm -lsocket -ladm -lnetsnmp -lcrypto

static char snmpreauth[]=".1.3.6.1.4.1.2352.2.14.1.2.1.1.";

struct snmp_session session, *ss;
struct snmp_pdu *response;
struct snmp_pdu *pdu;

char snmpcommunity[32];
char snmpstr[256];
char tmpstr[128];
char *endptr;

oid name[512];
int name_length;
int cnt,id=0;
int snmpsetvalue=1;

init_mib();
add_mibdir("/opt/weblogin/mibs");
   // include Redback Mibs file


snmp_sess_init(&session);
session.version=SNMP_VERSION_1;
session.peername=strdup(data.nas_address);
session.community=strdup(snmpcommunity);
session.community_len=strlen(session.community);
session.retries=0;
session.timeout=12000;
session.sessid=strtol(data.timeid, &endptr, 0);

SOCK_STARTUP;


    /* Macro
     * open an SNMP session
     */

  ss = snmp_open(&session);
    if (ss == NULL) {
        /*
         * diagnose snmp_open errors with the input netsnmp_session pointer
         */
        snmp_sess_perror("snmptable", &session);
        SOCK_CLEANUP;
    }


    /*
     * create PDU for SET request and add object names and values to request
     */

    pdu = (struct snmp_pdu *)snmp_pdu_create(SNMP_MSG_SET);
	if(pdu==NULL)
  	{
    		printf("Unable to create the pdu");
  	}

    sprintf(snmpstr,"%s17",snmpreauth);
	for(cnt=0;cnt<17;cnt++)
		{
		sprintf(tmpstr,".%d",(char *)data.session_id[cnt]);
		            // data.session_id MAC format string

		strcat(snmpstr,tmpstr);
		}

//FIXME
name_length=512;

if(!read_objid(snmpstr,name,&name_length)) {
  printf("Error in read_objid");
  exit(1);
};

snmp_pdu_add_variable(pdu,name,name_length,ASN_INTEGER,
  &snmpsetvalue,sizeof(snmpsetvalue));

    status = snmp_synch_response(ss, pdu, &response);
         // sync snmp

    if (status == STAT_SUCCESS) {
        if (response->errstat == SNMP_ERR_NOERROR) {
        }
        exitval = 2;

    } else if (status == STAT_TIMEOUT) {
        fprintf(stderr, "SNMP Timeout: No Response from %s",
                session.peername);
        exitval = 1;
    } else {
        snmp_sess_perror("snmpset", ss);
	printf("snmp session else");
        exitval = 1;
    }

    if (response)
        snmp_free_pdu(response);

    snmp_close(ss);

SOCK_CLEANUP;

/* Macro off
 * final a snmp session
 */