ack/lib/minix/include/ansi.h
1991-09-03 11:54:28 +00:00

55 lines
1.6 KiB
C

/* The <ansi.h> header checks whether the compiler claims conformance to ANSI
* Standard C. If so, the symbol _ANSI is defined as 1, otherwise it is
* defined as 0. Based on the result, a macro
*
* _PROTOTYPE(function, params)
*
* is defined. This macro expands in different ways, generating either
* ANSI Standard C prototypes or old-style K&R (Kernighan & Ritchie)
* prototypes, as needed. Finally, some programs use _CONST, _VOIDSTAR etc
* in such a way that they are portable over both ANSI and K&R compilers.
* The appropriate macros are defined here.
*/
#ifndef _ANSI_H
#define _ANSI_H
/* ANSI C requires __STDC__ to be defined as 1 for an ANSI C compiler.
* Some half-ANSI compilers define it as 0. Get around this here.
*/
#define _ANSI 0 /* 0 if compiler is not ANSI C, 1 if it is */
#ifdef __STDC__ /* __STDC__ defined for (near) ANSI compilers*/
#if __STDC__ == 1 /* __STDC__ == 1 for conformant compilers */
#undef _ANSI /* get rid of above definition */
#define _ANSI 1 /* _ANSI = 1 for ANSI C compilers */
#endif
#endif
/* At this point, _ANSI has been set correctly to 0 or 1. Define the
* _PROTOTYPE macro to either expand both of its arguments (ANSI prototypes),
* only the function name (K&R prototypes).
*/
#if _ANSI
#define _PROTOTYPE(function, params) function params
#define _VOIDSTAR void *
#define _VOID void
#define _CONST const
#define _VOLATILE volatile
#define _SIZET size_t
#else
#define _PROTOTYPE(function, params) function()
#define _VOIDSTAR void *
#define _VOID void
#define _CONST
#define _VOLATILE
#define _SIZET int
#endif /* _ANSI */
#endif /* ANSI_H */