Linux Manuals session 3

register_config_handler, register_const_config_handler, register_prenetsnmp_mib_handler, unregister_config_handler, register_mib_handlers, unregister_all_config_handlers, register_app_config_handler, register_app_prenetsnmp_mib_handler, unregister_app_config_handler, read_configs, read_premib_configs, read_config_print_usage, config_perror, config_pwarn – netsnmp_config_api functions Synopsis #include <net-snmp/config_api.h> Config Handlers struct config_line * register_config_handler(const char *filePrefix, const char *token, void (*parser)(const char *, char *), void (*releaser)(void), const char *usageLine); struct config_line * register_const_config_handler(const char *filePrefix, const char *token, void (*parser)(const char *,…

cache_handler – Maintains a cache of data for use by lower level handlers. Functions netsnmp_cache * netsnmp_cache_get_head (void) get cache head netsnmp_cache * netsnmp_cache_find_by_oid (oid *rootoid, int rootoid_len) find existing cache netsnmp_cache * netsnmp_cache_create (int timeout, NetsnmpCacheLoad *load_hook, NetsnmpCacheFree *free_hook, oid *rootoid, int rootoid_len) returns a cache unsigned int netsnmp_cache_timer_start (netsnmp_cache *cache) starts the recurring…

bulk_to_next – Convert GETBULK requests into GETNEXT requests for the handler. Functions netsnmp_mib_handler * netsnmp_get_bulk_to_next_handler (void) returns a bulk_to_next handler that can be injected into a given handler chain. void netsnmp_bulk_to_next_fix_requests (netsnmp_request_info *requests) takes answered requests and decrements the repeat count and updates the requests to the next to-do varbind in the list int netsnmp_bulk_to_next_helper…

baby_steps – Calls your handler in baby_steps for set processing. Modules baby_steps_access_multiplexer: calls individual access methods based on baby_step mode. Functions netsnmp_mib_handler * netsnmp_baby_steps_handler_get (u_long modes) returns a baby_steps handler that can be injected into a given handler chain. void netsnmp_baby_steps_handler_init (void) initializes the baby_steps helper which then registers a baby_steps handler as a run-time…

netsnmp_agent_api – embedding an agent into a external application Synopsis #include <net-snmp/agent/net-snmp-agent-includes.h> #include <net-snmp/net-snmp-config.h> #include <net-snmp/net-snmp-includes.h> int main(int argc, char *argv[]) { int agentx_subagent = 1; /* Change this if you’re a master agent. */ snmp_enable_stderrlog(); /* If we’re an AgentX subagent… */ if (agentx_subagent) { /* …make us an AgentX client. */ netsnmp_ds_set_boolean(NETSNMP_DS_APPLICATION_ID, NETSNMP_DS_AGENT_ROLE,…

The Net-SNMP agent – The snmp agent responds to SNMP queries from management stations. Modules Net-SNMP Agent handler and extensibility API The basic theory goes something like this: In the past, with the original mib module api (which derived from the original CMU SNMP code) the underlying mib modules were passed very little information (only…

Container_iterator – Typedefs typedef int( Netsnmp_Iterator_Loop_Key )(void *iterator_ctx, netsnmp_ref_void *loop_ctx, netsnmp_ref_void *key) typedef int( Netsnmp_Iterator_Loop_Data )(void *iterator_ctx, netsnmp_ref_void *loop_ctx, netsnmp_ref_void *data) typedef int( Netsnmp_Iterator_Ctx )(void *iterator_ctx, netsnmp_ref_void *loop_ctx) typedef int( Netsnmp_Iterator_Ctx_Dup )(void *iterator_ctx, netsnmp_ref_void *loop_ctx, netsnmp_ref_void *dup_ctx, int reuse) typedef int( Netsnmp_Iterator_Op )(void *iterator_ctx) typedef int( Netsnmp_Iterator_Data )(void *iterator_ctx, const void *data) Functions void netsnmp_container_iterator_init…

netlink – Netlink macros Synopsis #include <asm/types.h> #include <linux/netlink.h> int NLMSG_ALIGN(size_t len); int NLMSG_LENGTH(size_t len); int NLMSG_SPACE(size_t len); void *NLMSG_DATA(struct nlmsghdr *nlh); struct nlmsghdr *NLMSG_NEXT(struct nlmsghdr *nlh, int len); int NLMSG_OK(struct nlmsghdr *nlh, int len); int NLMSG_PAYLOAD(struct nlmsghdr *nlh, int len); Description <linux/netlink.h> defines several standard macros to access or create a netlink datagram. They…

netcdf – Unidata Network Common Data Form (netCDF) library, version 3 interface Synopsis use netcdf Most Systems: f90 … -lnetcdf CRAY PVP Systems: f90 -dp -i64 … -lnetcdf Library Version This document describes version 3 of Unidata netCDF data-access interface for the Fortran-90 programming language. character*80 nf90_inq_libvers() character(len=80) :: nf90_inq_libvers Returns a string identifying the…

netcdf – Unidata’s Network Common Data Form (netCDF) library interface Synopsis include netcdf.inc Most Systems: f77 … -lnetcdf CRAY PVP Systems: f90 -dp -i64 … -lnetcdf Complete documentation for the netCDF libraries can be found at the netCDF website: http://www.unidata.ucar.edu/software/netcdf/. Library Version This document describes version 3 of Unidata netCDF data-access interface for the FORTRAN…

netcdf – Unidata’s Network Common Data Form (netCDF) library interface Synopsis #include "netcdf.h" cc … -lnetcdf -lhdf5_hl -lhdf5 -lz -lm Complete documentation for the netCDF libraries can be found at the netCDF website: http://www.unidata.ucar.edu/software/netcdf/. Library Version This document describes versions 3 and 4 of Unidata netCDF data-access interface for the C programming language. const char*…

netcdf – Unidata Network Common Data Form (netCDF-2) library Warning The interface described here is obsolete, but included because the perl module still use it. Synopsis #include <netcdf.h> int nccreate(const char* path, int cmode) int ncopen(const char* path, int mode) int ncredef(int ncid) int ncsetfill(int ncid, int fillmode) int ncendef(int ncid) int ncclose(int ncid) int…

nerr_register Synopsis #include <util/neo_err.h> NEOERR *nerr_register (NERR_TYPE *err, const char *name); Arguments err – pointer to a NERR_TYPE name – pretty name for the error type Description register an error type. This will assign a numeric value to the type, and keep track of the "pretty name" for it. See Also nerr_error_traceback(3), nerr_pass(3), nerr_error_string(3), defined(3),…

nerr_pass_ctx Synopsis #include <util/neo_err.h> nerr_pass_ctx() Arguments with the macro, the function name, file and lineno are automagically recorded. Just pass the error and a printf format string giving more information about where the error is occuring. Description this function is used to pass an error up a level in the call chain (ie, if the…

nerr_pass Synopsis #include <util/neo_err.h> nerr_pass() Arguments with the macro, the function name, file and lineno are automagically recorded. Just pass the error. Description this function is used to pass an error up a level in the call chain (ie, if the error isn’t handled at the current level). This allows us to track the traceback…

nerr_match Synopsis #include <util/neo_err.h> int nerr_match(NEOERR *err, NERR_TYPE type); Arguments err – the NEOERR that has an error. type – the NEOERR type, as registered with nerr_register Description nerr_match is used to walk the NEOERR chain and match the error against a specific error type. In exception parlance, this would be the equivalent of "catch"….

nerr_log_error Synopsis #include <util/neo_err.h> void nerr_log_error(NEOERR *err); Description currently, this prints out the error to stderr, and free’s the error chain See Also nerr_error_traceback(3), nerr_pass(3), nerr_error_string(3), defined(3), nerr_pass_ctx(3), nerr_passf(3), nerr_init(3), nerr_match(3), nerr_log_error(3), nerr_ignore(3), nerr_register(3), nerr_handle

nerr_init Synopsis #include <util/neo_err.h> NEOERR *nerr_init (void); Arguments None Description initialize the NEOERR system. Can be called more than once. Is not thread safe. This registers all of the built in error types as defined at the top of this file. If you don’t call this, all exceptions will be returned as UnknownError. See Also…

nerr_ignore Synopsis #include <util/neo_err.h> void nerr_ignore(NEOERR **err); Description you should only call this if you actually handle the error (should I rename it?). Free’s the error chain. See Also nerr_error_traceback(3), nerr_pass(3), nerr_error_string(3), defined(3), nerr_pass_ctx(3), nerr_passf(3), nerr_init(3), nerr_match(3), nerr_log_error(3), nerr_ignore(3), nerr_register(3), nerr_handle

nerr_handle Synopsis #include <util/neo_err.h> int nerr_handle(NEOERR **err, NERR_TYPE type); Arguments err – pointer to a pointer NEOERR type – the NEOERR type, as registered with nerr_register Description nerr_handle is a convenience function. It is the equivalent of nerr_match, but it will also deallocate the error chain on a match. See Also nerr_error_traceback(3), nerr_pass(3), nerr_error_string(3), defined(3),…