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Atari Mega Archive 2
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include
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stdarg.h
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C/C++ Source or Header
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1990-07-23
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/* The <stdarg.h> header is ANSI's way to handle variable numbers of params.
* Some programming languages require a function that is declared with n
* parameters to be called with n parameters. C does not. A function may
* called with more parameters than it is declared with. The well-known
* printf function, for example, may have arbitrarily many parameters.
* The question arises how one can access all the parameters in a portable
* way. The C standard defines three macros that programs can use to
* advance through the parameter list. The definition of these macros for
* MINIX are given in this file. The three macros are:
*
* va_start(ap, parmN) prepare to access parameters
* va_arg(ap, type) get next parameter value and type
* va_end(ap) access is finished
*/
#ifndef _STDARG_H
#define _STDARG_H
typedef char *va_list;
#define __vasz(x) ((sizeof(x)+sizeof(int)-1) & ~(sizeof(int) -1))
#define va_start(ap, parmN) ((ap) = (va_list)&parmN + __vasz(parmN))
#define va_arg(ap, type) \
(*((type *)((va_list)((ap) = (void *)((va_list)(ap) + __vasz(type))) \
- __vasz(type))))
#define va_end(ap)
#endif /* _STDARG_H */