va_arg

Parameters

ap

Object of type va_list carrying information about the current retrieval state of a variable argument list. This object shall have been initialized by an initial call to va_start or va_copy and not have been released with va_end.

type

A type name. This type name is used as the type of the expression this macro expands to (i.e., its return type).
For a type expression to be suitable for its use with va_arg, it must be such that type* produces a pointer to type.
The type shall be compatible with type of the extracted argument (as promoted according to the default argument promotions), or one be the unsigned version of the other, or one be a void pointer and the other some other pointer type.

Return Value

Example

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/* va_arg example */
#include <stdio.h>      /* printf */
#include <stdarg.h>     /* va_list, va_start, va_arg, va_end */
int FindMax (int n, ...)
{
  int i,val,largest;
  va_list vl;
  va_start(vl,n);
  largest=va_arg(vl,int);
  for (i=1;i<n;i++)
  {
    val=va_arg(vl,int);
    largest=(largest>val)?largest:val;
  }
  va_end(vl);
  return largest;
}
int main ()
{
  int m;
  m= FindMax (7,702,422,631,834,892,104,772);
  printf ("The largest value is: %d\n",m);
  return 0;
}

The largest value is: 892

See also

va_start

Initialize a variable argument list (macro)

va_end

End using variable argument list (macro)

va_list

Type to hold information about variable arguments (type)

vsprintf

Write formatted data from variable argument list to string (function)