CC78K0S Datasheet, PDF (193/520 Pages) NEC – C Compiler Ver.1.30 or Later Language

CHAPTER 10 LIBRARY FUNCTIONS
va_start (normal model only)
va_arg (normal model only)
va_end (normal model only)
Special Functions
EXPLANATION
va_start
• In the va_start macro, the argument ap must be a va_list type (char* type) object.
• A pointer to the next argument of parmN is stored in ap.
• parmN is the name of the last (right-most) parameter specified in the function's prototype.
• If parmN has the register storage class, proper operation of this function is not guaranteed.
va_arg
• In the va_arg macro, the argument ap must be the same as the va_list type object initialized with va_start
(otherwise normal operation is not guaranteed).
• va_arg returns a value in the relevant place of variable arguments as a type of type.
The relevant place is the first variable argument immediately after va_start and each va_arg following that.
• If the argument pointer ap is a null pointer, va_arg returns 0 (of type type).
va_end
• The va_end macro sets a null pointer in the argument pointer ap to inform the macro processor that all the
parameters in the variable argument list have been processed.
User’s Manual U14872EJ1V0UM
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