GetHostByName Method of the IFWXSession Interface

The GetHostByName method retrieves host information corresponding to a host name. This method is similar to the Winsock gethostbyname function.


HRESULT GetHostByName(
  [in]	 const char* name,
  [out]	char* buf,
  [in, out]  int* buflen



Pointer to a null-terminated string that specifies the name of the host. UTF-8 encoding is expected in this parameter.


Pointer to the data area to receive the hostent data. The data area must be larger than the size of a hostent structure because the supplied data area is used by Windows Sockets (Winsock) to contain a hostent structure and all of the data referenced by members of the hostent structure. A buffer of MAXGETHOSTSTRUCT bytes is recommended. The strings returned in the structure are encoded using the current system ANSI code page (ACP).


On input, specifies the size of data area for the buf parameter. If the buffer is too small, the error code HRESULT_FROM_WIN32(ERROR_INSUFFICIENT_BUFFER) is returned and the buflen parameter receives the size of the required buffer.

Return Value


The method was successful. The buffer was filled with the host information.


Insufficient buffer space was provided. That is, the buffer pointed to by buf is not large enough to contain the host information.


The name specified could not be found in the relevant database.


No response was received from an authoritative server.


The name specified is valid and was found in the database, but no information of the type requested is associated with it.


Like the IFWXFirewall::GetHostByName method, this method checks permissions and policy rules, prior to providing the address. If there are no permissions or if the policy rules do not allow access, the host information will not be provided, and the method returns HRESULT_FROM_WIN32(WSAHOST_NOT_FOUND). This method also logs the name resolution and can use autodial to dial out for the name resolution.


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

Declared in Wspfwext.idl.


Requires Wspsrv.exe.

See Also


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Build date: 11/30/2009

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