The CACLSID structure defines a counted array of GUID (as specified in [MS-DTYP] section 2.3.4) values.
typedef struct tagCACLSID {
unsigned long cElems;
[size_is(cElems)] GUID* pElems;
} CACLSID;
cElems: MUST be set to the total number of elements of the array.
pElems: An array of GUID (as specified in [MS-DTYP] section 2.3.4) values.