Base Type Specifiers

The following table lists the IDL base data type specifiers. Where applicable, the table shows the size of the corresponding transmittable type and the type macro emitted by the IDL compiler for resulting declarations.

Base Data Type Specifiers

	Specifier			Type Macro
(sign)	(size)	(type)	Size	Emitted by idl
	small	int	8 bits	idl_small_int
	short	int	16 bits	idl_short_int
	long	int	32 bits	idl_long_int
	hyper	int	64 bits	idl_hyper_int
unsigned	small	int	8 bits	idl_usmall_int
unsigned	short	int	16 bits	idl_ushort_int
unsigned	long	int	32 bits	idl_ulong_int
unsigned	hyper	int	64 bits	idl_uhyper_int
		float	32 bits	idl_short_float
		double	64 bits	idl_long_float
		char	8 bits	idl_char
		boolean	8 bits	idl_boolean
		byte	8 bits	idl_byte
		void	-	idl_void_p_t
		handle_t	-	-

The base types are described individually later in this topic.

Note that you can use the idl_ macros in the code you write for an application to ensure that your type declarations are consistent with those in the stubs, even when the application is ported to another platform. The idl_ macros are especially useful when passing constant values to RPC calls. For maximum portability, all constants passed to RPC calls declared in your network interfaces should be cast to the appropriate type because the size of integer constants (like the size of the int data type) is ambiguous in the C language.

The idl_ macros are defined in dce/idlbase.h, which is included by header files that the IDL compiler generates.