Compaq AAR04BCTE manual ESNMP API Routines inst2ip Description, Examples

eSNMP API Routines inst2ip

Description

Use the EXACT mode for evaluating an instance for Get and Set operations. For GetNext and GetBulk operations, use the NEXT mode. When using NEXT mode, this routine assumes that the search for data will be performed using greater than or equal to matches.

Return Values

Carry value is 0	The routine completed successfully.
Carry value is 1	For EXACT match, an error occurred. For NEXT
	match, there was a carry. (If there was a carry,
	the returned ipaddr is 0.)

Examples

1.The following example converts an instance to an IP address for a Get operation, which is an EXACT match.

#include <esnmp.h>

OID	*incoming = &method->varbind->name;
OBJECT	*object = method->object;
int instLength;
unsigned int instance[6];
unsigned int ip_addr;
int	iface;

-- The instance is N.1.A.A.A.A where the A’s are the IP address-- instLength = oid2instance(incoming, object, instance, 6);

if (instLength == 6 && !inst2ip(&instance[2], 4, &ip_addr, TRUE,0)) { iface = (int) instance[0];

}

else

return ESNMP_MTHD_noSuchInstance;

2.The following example shows a GetNext operation in which there is only one key or in which the ipaddr value is the least significant part of the key. This is a NEXT match; therefore, a value of 1 is passed back for the carry value.

#include <esnmp.h>

OID	*incoming	= &method->varbind->name;
OBJECT	*object	= method->object;
int instLength;

unsigned int instance[6]; unsigned int ip_addr;

int iface;

-- The instance is N.1.A.A.A.A where the A’s are the IP address-- instLength = oid2instance(incoming, object, instance, 6);

iface = (instLength < 1) ? 0 :(int) instance[0];

iface += inst2ip(&instance[2], instLength - 2, &ip_addr, FALSE, 1);

3.In the following example, the search key consists of multiple parts. If you are doing a GetNext operation, you must find the next possible value for the search key, so that you can perform a cascaded greater-than or equal-to search.

eSNMP API Routines 5–45