SNMP Manager Programmer's Guide

Encoding and Decoding Packets

SNMP Manager Programmer’s Guide–134249

6-5

Releasing Encoded-Packet Buffer Memory

When you no longer need a buffer for which space has been dynamically allocated by

you or by Manager Services, you use the EBufferClean() function to release allocated

memory:

EBufferClean(&ebuff);

This function releases memory allocated for the buffer and calls EBufferInitialize(),

setting the buffer descriptors as described for that function.

Using a Buffer for General Purposes

The Manager Services buffer manipulation functions are useful for handling any buffer

you manage using EBUFFER_T descriptors. For example, they can be used to

manipulate the two EBUFFER_T fields in the packet structure: community and

std_pdu.std_vbl.vblist.value_u.v_string.

The previous subsection describes some of the buffer manipulation functions:

EBufferInitialize(), EBufferSetup(), SNMP_memory_alloc(), and EBufferClean(). This

subsection introduces the remaining functions.

Four of the functions retrieve information about the buffer and its contents:

EBufferStart() returns the value of start_bp.

EBufferNext() returns the value of next_bp.

EBufferRemaining() returns the value of remaining.

EBufferUsed() returns the number of bytes between start_bp and next_bp.

Three additional Manager Services functions are available for manipulating an

EBUFFER_T buffer:

•

EBufferReset() resets the buffer descriptors for a buffer already allocated:

EBufferReset(ebuffp);

The buffer descriptors after an EBufferReset() call are exactly as described for

EBufferSetup().

602

remaining

start_bp next_bp

(EBufferStart())

(EBufferNext())

EBufferRemaining()

(EBufferUsed())