Managing Object Identifiers

The WinSNMP API provides several WinSNMP utility functions that simplify the manipulation of object identifiers for WinSNMP applications.

The SnmpOidToStr function converts the internal binary representation of an object identifier to its dotted numeric string format. When you call SnmpOidToStr, specify a string buffer of MAXOBJIDSTRSIZE length (1408 bytes) to ensure that the output buffer is large enough to hold the converted string. To convert an object identifier from the dotted numeric string format to its internal binary representation, call the SnmpStrToOid function.

To copy an SNMP object identifier call the SnmpOidCopy function. This function allocates any necessary memory for the new object identifier.

A WinSNMP application must call the SnmpFreeDescriptor function to free resources allocated for the ptr member of the smiOID structure specified by both the SnmpStrToOid and the SnmpOidCopy functions.

The SnmpOidCompare function compares two SNMP object identifiers. The WinSNMP application can specify the number of subidentifiers to compare. Call SnmpOidCompare to determine whether two object identifiers have common prefixes.

For additional information about managing the memory allocated for object identifiers, see Allocating WinSNMP Memory Objects.