Zilog EZ80F916 - Manual (Page 347)

UM014423-0607 C Standard Library
ZiLOG Developer Studio II
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A function can be called with a variable number of arguments of varying types. “Function
Definitions” parameter list contains one or more parameters. The rightmost parameter
plays a special role in the access mechanism and is designated parmN in this description.
Type
Variable Argument List Access Macros and Function
The va_start and va_arg macros described in this section are implemented as macros, not
as real functions. If
#undef is used to remove a macro definition and obtain access to a
real function, the behavior is undefined.
Functions
Input/Output
The < stdio.h > header declares input and output functions.
Macro
Functions
Formatted Input/Output
va_list An array type suitable for holding information needed by the macro va_arg and the
function va_end. The called function declares a variable (referred to as ap in this
section) having type va_list. The variable ap can be passed as an argument to another
function.
void va_start(va_list ap, parmN); Sets pointer to beginning of argument list.
type va_arg (va_list ap, type); Retrieves argument from list.
void va_end(va_list ap); Resets pointer.
EOF Expands to a negative integral constant. Returned by functions to indicate end of
file.
int printf(const char *format, ...); Writes formatted data to stdout.
int scanf(const char *format, ...); Reads formatted data from stdin.
int sprintf(char *s, const char *format, ...); Writes formatted data to string.
int sscanf(const char *s, const char *format, ...); Reads formatted data from string.
int vprintf(const char *format, va_list arg); Writes formatted data to a stdout.
int vsprintf(char *s, const char *format, va_list arg); Writes formatted data to a string.