GUID

The GUID structure describes a globally unique identifier.

Quick Info

typedef struct _GUID 
{ 
    unsigned long        Data1; 
    unsigned short       Data2; 
    unsigned short       Data3; 
    unsigned char        Data4[8]; 
} GUID; 
 

Members

Data1

An unsigned long integer data value.

Data2

An unsigned short integer data value.

Data3

An unsigned short integer data value.

Data4

An array of unsigned characters.

Remarks

GUID structures are used in MAPI as follows:

• In the MAPIUID structures that uniquely identify service providers.
• For interface identifiers.
• In the property set names of named properties.

Message store and address book providers call the Microsoft utility UUIDGEN.EXE to generate a GUID structure to use in their MAPIUID structure. By passing the resulting MAPIUID to IMAPISupport::SetProviderUID, these service providers inform MAPI of their unique identifier.

Also, they are used in the implementation of Microsoft Remote Procedure Call (RPC) and the Object Description Language (ODL). For more information about these uses, see the Microsoft RPC Programmer's Guide and Reference, OLE Programmer's Reference, and Inside OLE, Second Edition.

The GUID structure is defined in the Win32 Programmer's Reference. Specific values for GUID structures that are used within MAPI are defined in the MAPI header file MAPIGUID.H.

See Also

ID Structures, MAPIUID