the accurate description of the snmp error

Where can I find the accurate description of the snmp error? 

 

Which error is right when a invalid user to access mib, such as a SNMPv1
read-only user does a configuration, or a unknown user read something?

 

Errors definitions are extracted in the file snmp.h for your reference:

/* in SNMPv1, SNMPsec, SNMPv2p, SNMPv2c, SNMPv2u, SNMPv2*, and SNMPv3
PDUs */

#define SNMP_ERR_NOERROR                (0)     /* XXX  Used only for
PDUs? */

#define SNMP_ERR_TOOBIG                 (1)

#define SNMP_ERR_NOSUCHNAME             (2)

#define SNMP_ERR_BADVALUE               (3)

#define SNMP_ERR_READONLY               (4)

#define SNMP_ERR_GENERR                 (5)

/* in SNMPv2p, SNMPv2c, SNMPv2u, SNMPv2*, and SNMPv3 PDUs */

#define SNMP_ERR_NOACCESS        (6)

#define SNMP_ERR_WRONGTYPE       (7)

#define SNMP_ERR_WRONGLENGTH         (8)

#define SNMP_ERR_WRONGENCODING       (9)

#define SNMP_ERR_WRONGVALUE      (10)

#define SNMP_ERR_NOCREATION      (11)

#define SNMP_ERR_INCONSISTENTVALUE   (12)

#define SNMP_ERR_RESOURCEUNAVAILABLE (13)

#define SNMP_ERR_COMMITFAILED        (14)

#define SNMP_ERR_UNDOFAILED      (15)

#define SNMP_ERR_AUTHORIZATIONERROR  (16)

#define SNMP_ERR_NOTWRITABLE         (17)

/* in SNMPv2c, SNMPv2u, SNMPv2*, and SNMPv3 PDUs */

#define SNMP_ERR_INCONSISTENTNAME    (18)