SHWindowsPolicyGetValue

Declaration

HRESULT
SHWindowsPolicyGetValue (
    REFGUID rpolid,
    PVOID pvData,
    DWORD *pcbData);

Parameters

The rpolid argument provides by reference a GUID for the policy whose value is wanted. The supported policy identifiers are listed separately, since there are very many.

The pvData argument provides the address of a buffer that is to receive data that is the policy’s value. This argument can be NULL to mean that there is no buffer and that the data is not wanted.

The pcbData argument provides the address of a variable that plays different roles on input and output. On input, the variable provides the size of the buffer, in bytes. This size is ignored if pvData is NULL, because there is then no buffer. On output, the variable receives the size of the data, in bytes. This argument can be NULL to mean that the size of the buffer is zero (if a buffer is even given) and that the size of the data is not wanted.

Return Value

The function returns zero for success, else an error code.

Of particular interest are the cases in which the value is accessible but has more data than can fit in the given buffer, including because there is no buffer:

• If pvData is NULL, the caller did not ask for data and is not denied anything that was asked for. The function therefore succeeds. If pcbData is not NULL, the variable at pcbData receives the size of the data.
• If pvData is not NULL, the caller asked for data, which the function cannot deliver. The function therefore fails. The error code is 0x800700EA (i.e., the HRESULT from ERROR_MORE_DATA). The contents of the buffer at pvData are undefined. If pcbData is not NULL, the variable at pcbData receives the size of the data.

Behaviour

IN PROGRESS

Availability

The SHWindowsPolicyGetValue function is exported from SHLWAPI as ordinal 560 in version 6.0 from Windows XP SP2 and Windows Server 2003 SP1, and higher.