1MIB2C(1) Net-SNMP MIB2C(1)
2
6 mib2c -- generate template code for extending the agent
7
9 mib2c [-h] -c CONFIGFILE [-I PATH] [-f OUTNAME] [-i][-s][-q][-S
10 VAR=VAL] MIBNODE
11
13 The mib2c tool is designed to take a portion of the MIB tree (as de‐
14 fined by a MIB file) and generate the template C code necessary to im‐
15 plement the relevant management objects within it.
16 In order to implement a new MIB module, three files are necessary:
18 - MIB definition file
20 - C header file
21 - C implementation file.
22 The mib2c tool uses the MIB definition file to produce the two C code
24 files. Thus, mib2c generates a template that you can edit to add logic
25 necessary to obtain information from the operating system or applica‐
26 tion to complete the module.
27 MIBNODE is the top level mib node you want to generate code for. You
29 must give mib2c a mib node (e.g. ifTable) on the command line, not a
30 mib file. This is the single most common mistake.
31 The mib2c tool accepts both SMIv1 and SMIv2 MIBs.
33 mib2c needs to be able to find and load a MIB file in order to generate
35 C code for the MIB. To enable mib2c to find the MIB file, set the MIBS
36 environment variable to include the MIB file you are using. An example
37 of setting this environment variable is:
38 MIBS=+NET-SNMP-TUTORIAL-MIB
40 or
42 MIBS=ALL
44 The first example ensures that mib2c finds the NET-SNMP-TUTORIAL-MIB
46 mib, in addition to the default MIB modules. The default list of MIB
47 modules is set when the suite is first configured and built and basi‐
48 cally corresponds to the list of modules that the agent supports. The
49 second example ensures that mib2c finds all MIBs in the search location
50 for MIB files. The default search location for MIB files is
51 /usr/share/snmp/mibs. This search location can be modified by the MIB‐
52 DIRS environment variable.
53 Both the MIB files to be loaded and the MIB file search location can
55 also be configured in the snmp.conf file. Please see snmp.conf(5) for
56 more information.
57 The generated *.c and *.h files will be created in the current working
59 directory.
60
62 -h Display a help message.
63 -c CONFIGFILE
65 Use CONFIGFILE when generating code. These files will be
66 searched for first in the current directory and then in the
67 /usr/share directory (which is where the default mib2c configu‐
68 ration files can be found). Running mib2c without the -c CON‐
69 FIGFILE option will display a description of the valid values
70 for CONFIGFILE, that is, the available config files, including
71 new ones that you might author.
72 For example,
74 % mib2c ifTable
76 will display a description of the currently available values for
78 CONFIGFILE.
79 The following values are supported for CONFIGFILE:
81 mib2c.mfd.conf
83 mib2c.scalar.conf
84 mib2c.int_watch.conf
85 mib2c.iterate.conf
86 mib2c.create-dataset.conf
87 mib2c.array-user.conf
88 mib2c.column_defines.conf
89 mib2c.column_enums.conf
90 GENERATING CODE FOR SCALAR OBJECTS:
92 If you're writing code for some scalars, run:
94 mib2c -c mib2c.scalar.conf MIBNODE
96 If you want to magically "tie" integer variables to integer
98 scalars, use:
99 mib2c -c mib2c.int_watch.conf MIBNODE
101 GENERATING CODE FOR TABLES:
103 The recommended configuration file for tables is the MIBs for
105 Dummies, or MFD, configuration file. It hides as much of the
106 SNMP details as possible, generating small, easy to understand
107 functions. It is also the most flexible and well documented
108 configuration file. See the agent/mibgroup/if-
109 mib/ifTable/ifTable*.c files for an example:
110 mib2c -c mib2c.mfd.conf MIBNODE
112 If your table data is kept somewhere else (e.g. it's in the ker‐
114 nel and not in the memory of the agent itself) and you need to
115 "iterate" over it to find the right data for the SNMP row being
116 accessed. See the agent/mibgroup/mibII/vacm_context.c file for
117 an example:
118 mib2c -c mib2c.iterate.conf MIBNODE
120 If your table data is kept in the agent (i.e. it's not located
122 in an external source) and is purely data driven (i.e. you do
123 not need to perform any work when a set occurs). See the
124 agent/mibgroup/examples/data_set.c file for an example of such a
125 table:
126 mib2c -c mib2c.create-dataset.conf MIBNODE
128 If your table data is kept in the agent (i.e. it's not located
130 in an external source), and you can keep your data sorted by the
131 table index but you do need to perform work when a set occurs:
132 mib2c -c mib2c.array-user.conf MIBNODE
134 GENERATING HEADER FILE DEFINITIONS
136 To generate just a header with a define for each column number
138 in your table:
139 mib2c -c mib2c.column_defines.conf MIBNODE
141 To generate just a header with a define for each enum for any
143 column containing enums:
144 mib2c -c mib2c.column_enums.conf MIBNODE
146 GENERATING CODE FOR THE 4.X LINE OF CODE (THE OLDER API)
148 mib2c -c mib2c.old-api.conf MIBNODE
150 -IPATH Search for configuration files in PATH. Multiple paths can be
152 specified using multiple -I switches or by using one with a
153 comma separated list of paths in it.
154 -f OUTNAME
156 Places the output code into OUTNAME.c and OUTNAME.h. Normally,
157 mib2c will place the output code into files which correspond to
158 the table names it is generating code for, which is probably
159 what you want anyway.
160 -i Do not run indent on the resulting code.
162 -s Do not look for MIBNODE.sed and run sed on the resulting code.
164 This is useful to shorten long mib variable names in the code.
165 -q Run in "quiet" mode, which minimizes the status messages mib2c
167 generates.
168 -SVAR=VAL
170 Preset a variable VAR, in the mib2c.*.conf file, to the value
171 VAL. None of the existing mib2c configuration files
172 (mib2c.*.conf) currently makes use of this feature, however, so
173 this option should be considered available only for future use.
174
176 The following generates C template code for the header and implementa‐
177 tion files to implement UCD-DEMO-MIB::ucdDemoPublic.
178 % mib2c -c mib2c.scalar.conf ucdDemoPublic
180 writing to ucdDemoPublic.h
181 writing to ucdDemoPublic.c
182 running indent on ucdDemoPublic.h
183 running indent on ucdDemoPublic.c
184 The resulting ucdDemoPublic.c and ucdDemoPublic.h files are generated
186 the current working directory.
187 The following generates C template code for the header and implementa‐
189 tion files for the module to implement TCP-MIB::tcpConnTable.
190 % mib2c -c mib2c.iterate.conf tcpConnTable
192 writing to tcpConnTable.h
193 writing to tcpConnTable.c
194 running indent on tcpConnTable.h
195 running indent on tcpConnTable.c
196 The resulting tcpConnTable.c and tcpConnTable.h files are generated in
198 the current working directory.
199
201 snmpcmd(1), snmp.conf(5)
202V5.9.1 05 Apr 2010 MIB2C(1)