Compaq AAR04BCTE - Manual (Page 20)

Overview
1.6 The MIB Compiler
• Method routine function prototypes
The subtree_TBL.C file is an object file that contains the following:
• An array of integers representing the OIDs for each MIB variable
• An array of OBJECT structures
• An initialized SUBTREE structure
1.7 SNMP Versions
The extensible SNMP software supports SNMP Version 2, based on RFCs 1901
through 1908, including:
• The SNMP Version 2 structure of management information for SNMP Version
2 (SMI Version 2) and textual conventions.
• The eSNMP library API (SNMP Version 2), variable binding exceptions, and
error codes.
• SNMP Version 1 and SNMP Version 2 requests. Both versions are handled
by the master agent. SNMP Version 2 specific information from the subagent
is mapped, when necessary, to SNMP Version 1 adherent data (according
to RFC 2089). For example, if a management application makes a request
using SNMP Version 1 PDUs, the master agent replies using SNMP Version
1 PDUs, mapping any SNMP Version 2 SMI items received from subagents.
In most cases, subagents created with a previous version of the eSNMP
API do not require any code changes and do not have to be recompiled. The
circumstances under which recoding or recompiling are required are described
in Section 1.7.1.
1.7.1 Using Existing (SNMP Version 1) MIB Modules
Existing SNMP Version 1 MIB subagent executable files should be compatible
with the current SNMP Version 2 master agent without the need to recompile
and relink, with the following exceptions:
• Any program that relies on TCP/IP Services Version 4.1 or 4.2 kernel data
structures or access functions may run but may not return valid data. Such
programs should be rewritten.
• Programs linked against UCX$ACCESS_SHR.EXE, UCX$IPC_SHR.EXE, or
other older shareable images (except for UCX$ESNMP_SHR.EXE, which is
described in the next list item) may not run even when relinked. You may
need to either rewrite or both rewrite and recompile such programs. Note
that the Chess example image (UCX$CHESS_SUBAGENT.EXE) has been
updated and renamed TCPIP$CHESS_SUBAGENT.EXE.
• For programs linked against certain versions of UCX$ESNMP_SHR.EXE:
– Images associated with the following versions of TCP/IP Services will run
correctly without the need to relink them:
Version 4.1 ECO 9 and later
Version 4.2 ECO 1 and later
The installation of TCP/IP Services provides a backward-compatible
version of UCX$ESNMP_SHR.EXE in the SYS$SHARE directory. Do not
delete this image.
1–8 Overview