pDPIpacket()--Parse a DPI Packet

 #include <qtossapi.h>

 snmp_dpi_hdr  *pDPIpacket( unsigned char *packet_p );  

The pDPIpacket() function parses a serialized Distributed Protocol Interface (DPI) packet to make it available for processing by the subagent.

Authorities and Locks

None.

Parameters

packet_p

(Input) A pointer to a serialized (incoming) DPI packet.

Return Value

For more information, see "SNMP Subagent Problem Determination" in the Simple Network Management Protocol (SNMP) Support book.

Usage Notes

The pDPIpacket() function parses the buffer that is pointed to by the packet_p parameter. It ensures that the buffer contains a valid DPI packet and that the packet is for a DPI version and release that is supported by the DPI functions in use.

Typical follow-on processing will examine the packet_type in the returned snmp_dpi_hdr, and take various actions to process the various types of DPI packets that may arrive. A subagent would normally expect to handle all the possible DPI packet types listed in <qtossapi.h>, except SNMPv2 types (SNMP_DPI_GETBULK and SNMP_DPI_TRAPV2), and types sent only to SNMP agents (SNMP_DPI_OPEN, SNMP_DPI_REGISTER, SNMP_DPI_TRAP, and SNMP_DPI_INFORM). Note that a close or unregister packet can be sent from an agent to the subagent. And if the subagent receives an are-you-there packet, it should build and send a response packet with the proper error_code.

Related Information

• The <qtossapi.h> file (see Header Files for UNIX-Type Functions)
  
  
• fDPIparse()--Free Storage from DPI Packet Parse
  
  
• pDPIpacket()--Parse a DPI Packet

Example

See Code disclaimer information for information pertaining to code examples.

  #include <qtossapi.h>
  unsigned char       *pack_p;
  snmp_dpi_hdr        *hdr_p;

  hdr_p = pDPIpacket(pack_p);       /* Parse incoming packet. */
                                    /* Assume it's in pack_p. */
  if (hdr_p) {
     /* Analyze packet, and handle it. */
     switch( hdr_p->packet_type) {
        ...
        }
  }