Go to main content

man pages section 3: Library Interfaces and Headers

Exit Print View

Updated: Wednesday, July 27, 2022
 
 

snmp_add_null_var (3)

Name

snmp_add_null_var - snmp_pdu_add_variable, snmp_varlist_add_variable, snmp_add_null_var, snmp_clone_varbind, snmp_set_var_objid, snmp_set_var_value, snmp_set_var_typed_value, snmp_set_var_typed_integer, print_variable, fprint_variable, snprint_variable, print_value, fprint_value, netsnmp_varbind_api functions

Synopsis

#include <net-snmp/varbind_api.h>

Creation
netsnmp_variable_list *snmp_pdu_add_variable(
netsnmp_pdu *pdu,
const oid *objid, size_t objidlen,
u_char type, const void *value, size_t len);
netsnmp_variable_list *snmp_varlist_add_variable(
netsnmp_variable_list *varlist,
const oid *objid, size_t objidlen,
u_char type, const void *value, size_t len);
netsnmp_variable_list *snmp_add_null_var(
netsnmp_pdu *pdu,
const oid *objid, size_t objidlen);

netsnmp_variable_list *snmp_clone_varbind(
netsnmp_variable_list *varlist);

Setting Values
int  snmp_set_var_objid( netsnmp_variable_list* variable,
const oid * objid, size_t objidlen);
int  snmp_set_var_value( netsnmp_variable_list* variable,
const void * value, size_t vallen);
int  snmp_set_var_typed_value( netsnmp_variable_list* variable,
u_char type,
const void * value, size_t vallen);
int  snmp_set_var_typed_integer( netsnmp_variable_list* variable,
u_char type, long value);

Output
void  print_variable(const oid *objid, size_t objidlen,
const netsnmp_variable_list *variable);
void fprint_variable(FILE *fp,
const oid *objid, size_t objidlen,
const netsnmp_variable_list *variable);
int snprint_variable(char *buf, size_t len,
const oid *objid, size_t objidlen,
const netsnmp_variable_list *variable);

void  print_value(const oid *objid, size_t objidlen,
const netsnmp_variable_list *variable);
void fprint_value(FILE *fp,
const oid *objid, size_t objidlen,
const netsnmp_variable_list *variable);
int snprint_value(char *buf, size_t len,
const oid *objid, size_t objidlen,
const netsnmp_variable_list *variable);

Deletion
void snmp_free_var(       netsnmp_variable_list *variable);
void snmp_free_varbind( netsnmp_variable_list *variables);

Description

NETSNMP_VARBIND_API(3)             Net-SNMP             NETSNMP_VARBIND_API(3)



NAME
       snmp_pdu_add_variable,   snmp_varlist_add_variable,  snmp_add_null_var,
       snmp_clone_varbind,       snmp_set_var_objid,       snmp_set_var_value,
       snmp_set_var_typed_value,  snmp_set_var_typed_integer,  print_variable,
       fprint_variable,    snprint_variable,    print_value,     fprint_value,
       snprint_value,  snmp_free_var,  snmp_free_varbind - netsnmp_varbind_api
       functions

SYNOPSIS
       #include <net-snmp/varbind_api.h>

   Creation
       netsnmp_variable_list *snmp_pdu_add_variable(
                            netsnmp_pdu *pdu,
                            const oid *objid, size_t objidlen,
                            u_char type, const void *value, size_t len);
       netsnmp_variable_list *snmp_varlist_add_variable(
                            netsnmp_variable_list *varlist,
                            const oid *objid, size_t objidlen,
                            u_char type, const void *value, size_t len);
       netsnmp_variable_list *snmp_add_null_var(
                            netsnmp_pdu *pdu,
                            const oid *objid, size_t objidlen);

       netsnmp_variable_list *snmp_clone_varbind(
                            netsnmp_variable_list *varlist);

   Setting Values
       int  snmp_set_var_objid( netsnmp_variable_list* variable,
                            const oid * objid, size_t objidlen);
       int  snmp_set_var_value( netsnmp_variable_list* variable,
                            const void * value, size_t vallen);
       int  snmp_set_var_typed_value( netsnmp_variable_list* variable,
                            u_char type,
                            const void * value, size_t vallen);
       int  snmp_set_var_typed_integer( netsnmp_variable_list* variable,
                            u_char type, long value);

   Output
       void  print_variable(const oid *objid, size_t objidlen,
                            const netsnmp_variable_list *variable);
       void fprint_variable(FILE *fp,
                            const oid *objid, size_t objidlen,
                            const netsnmp_variable_list *variable);
       int snprint_variable(char *buf, size_t len,
                            const oid *objid, size_t objidlen,
                            const netsnmp_variable_list *variable);

       void  print_value(const oid *objid, size_t objidlen,
                            const netsnmp_variable_list *variable);
       void fprint_value(FILE *fp,
                            const oid *objid, size_t objidlen,
                            const netsnmp_variable_list *variable);
       int snprint_value(char *buf, size_t len,
                            const oid *objid, size_t objidlen,
                            const netsnmp_variable_list *variable);

   Deletion
       void snmp_free_var(       netsnmp_variable_list *variable);
       void snmp_free_varbind( netsnmp_variable_list *variables);

DESCRIPTION
       The functions dealing with variable bindings fall into  four  groups  -
       dealing  with  the  creation, setting of values, output and deletion of
       varbinds.

   Creation
       snmp_pdu_add_variable will create a new varbind structure,  initialised
       with  the name ( objid, objidlen ), syntax ( type ) and value ( value ,
       len ) provided.  This varbind is then added to the end of  the  varbind
       list in the given PDU.

       snmp_varlist_add_variable  is  similar,  but appends the new varbind to
       the end of the varbind list provided.  When adding the first varbind to
       an empty list, simply pass the address of the head of the list:

                netsnmp_variable_list *vl = NULL;
                snmp_varlist_add_variable(
                          &vl, name1, name1_len,
                          ASN_TYPE, &val1, val1_len);
                snmp_varlist_add_variable(
                          &vl, name2, name2_len,
                          ASN_TYPE, &val2, val2_len);

       In  both  cases,  the  routine will return a pointer to the new varbind
       structure (or NULL if the varbind creation fails).

       snmp_add_null_var is a convenience function to add an empty varbind  to
       the  PDU.   without needing to specify the NULL value explicitly.  This
       is the normal mechanism for constructing a GET (or similar) information
       retrieval request.
       Again, this returns a pointer to the new varbind, or NULL.

       snmp_clone_varbind  creates  a  copy  of  each varbind in the specified
       list, returning a pointer to the head of the new list (or NULL  if  the
       cloning fails).

   Setting of values
       snmp_set_var_objid sets the name of the varbind structure to the speci-
       fied OID.
       snmp_set_var_typed_value sets the syntax type and value of the  varbind
       structure.
       snmp_set_var_value sets the value of the varbind structure, leaving the
       syntax type unchanged.
       snmp_set_var_typed_integer is a convenience function to set the  syntax
       type and value for a 32-bit integer-based varbind.

       All  four of these return 0 if the assignment is successful, or 1 if it
       is not.

   Output
       print_variable  will  take  an  object  identifier  (as   returned   by
       read_objid,  snmp_parse_oid or get_module_node) and an instance of such
       a variable, and prints to the standard output the textual form  of  the
       object identifier together with the value of the variable.

       fprint_variable does the same, but prints to the FILE pointer specified
       by the initial parameter.

       snprint_variable prints the same information into the buffer pointed to
       by  buf  which  is  of length len.  It returns the number of characters
       printed, or -1 if the buffer was not large enough.  In the latter case,
       buf  will  typically  contained  a truncated version of the information
       (but this behaviour is not guaranteed).   This  function  replaces  the
       obsolete function sprint_variable.

       print_value, fprint_value, and snprint_value do the same as the equiva-
       lent print_variable routines, but only  displaying  the  value  of  the
       variable, without the corresponding object identifier.

       For displaying the OID of a varbind, see netsnmp_mib_api(3).

   Deletion
       snmp_free_var releases all memory used by the given varbind structure.
       snmp_free_varbind releases all memory used by each varbind structure in
       the varbind list provided.


ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       +---------------+---------------------------------+
       |ATTRIBUTE TYPE |        ATTRIBUTE VALUE          |
       +---------------+---------------------------------+
       |Availability   | system/management/snmp/net-snmp |
       +---------------+---------------------------------+
       |Stability      | Volatile                        |
       +---------------+---------------------------------+

SEE ALSO
       netsnmp_pdu_api(3) netsnmp_mib_api(3)



NOTES
       Source code for open source software components in Oracle  Solaris  can
       be found at https://www.oracle.com/downloads/opensource/solaris-source-
       code-downloads.html.

       This    software    was    built    from    source     available     at
       https://github.com/oracle/solaris-userland.    The  original  community
       source  was  downloaded   from    https://sourceforge.net/projects/net-
       snmp/files/net-snmp/5.8/net-snmp-5.8.tar.gz.

       Further information about this software can be found on the open source
       community website at http://www.net-snmp.org/.



V5.8                              13 Aug 2010           NETSNMP_VARBIND_API(3)