SnmpFreeDescriptor function (winsnmp.h)

[SNMP is available for use in the operating systems specified in the Requirements section. It may be altered or unavailable in subsequent versions. Instead, use Windows Remote Management, which is the Microsoft implementation of WS-Man.]

A WinSNMP application uses the SnmpFreeDescriptor function to inform the Microsoft WinSNMP implementation that it no longer requires access to a descriptor object. This WinSNMP function signals the implementation to free the memory it allocated for the descriptor object.


  [in] smiUINT32   syntax,
  [in] smiLPOPAQUE descriptor


[in] syntax

Specifies the syntax data type of the target descriptor object.

[in] descriptor

Pointer to an smiOPAQUE structure that contains the target descriptor object to release.

Return value

If the function succeeds, the return value is SNMPAPI_SUCCESS.

If the function fails, the return value is SNMPAPI_FAILURE. To get extended error information, call SnmpGetLastError specifying a NULL value in its session parameter. The SnmpGetLastError function can return one of the following errors.

Return code Description
The SnmpStartup function did not complete successfully.
An error occurred during memory allocation.
The syntax parameter is invalid.
The descriptor parameter is invalid. For additional information, see the following Remarks section.
An unknown or undefined error occurred.


The implementation allocates and deallocates memory for output descriptor objects with variable lengths. This memory allocation and deallocation are restricted to the implementation, except for the interface that the SnmpFreeDescriptor function provides. For additional information, see Freeing WinSNMP Descriptors.

The implementation returns the SNMPAPI_OPERATION_INVALID error code if the descriptor parameter specifies a memory allocation that the implementation released in a prior call to SnmpFreeDescriptor. The function returns the same error code if the descriptor parameter specifies a memory allocation that the implementation did not make for the calling WinSNMP application.


Minimum supported client Windows 2000 Professional [desktop apps only]
Minimum supported server Windows 2000 Server [desktop apps only]
Target Platform Windows
Header winsnmp.h
Library Wsnmp32.lib
DLL Wsnmp32.dll

See also




WinSNMP Functions

WinSNMP API Overview