AllocMem Callback Function

The AllocMem callback function is used to allocate memory from the process heap to a buffer. Any memory allocated by using this callback function will automatically be freed by the Forefront TMG Web proxy after the session ends (as indicated by the SF_NOTIFY_END_OF_NET_SESSION notification). If the memory cannot be allocated, this callback function returns NULL. For more information about the types of event notifications that are sent to Web filters, see Event Notifications.

The AllocMem callback function is declared as:


VOID* WINAPI * AllocMem(
  __in  struct _HTTP_FILTER_CONTEXT* pfc,
  __in  DWORD cbSize,
  __in  DWORD dwReserved



Pointer to the HTTP_FILTER_CONTEXT data structure that is associated with the current, active HTTP session. Pass the filter context in this parameter.


Indicates the size of the buffer to be allocated, in bytes.


Reserved for use by the server.

Return Value

This callback function does not return a value.


Server Requires Windows Server 2008.
Version Requires Forefront Threat Management Gateway (TMG).

Declared in Wpxhttpfilt.h.


Requires W3Filter.dll.

See Also

Callback Functions

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Build date: 11/30/2009

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