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#include <stdarg.h>
#include <stdio.h>
#include <assert.h>
// how to do it:
// once an ellipsis is seen in the called function, declare an array of
// appropriate size (sum of sizeofs+paddings) and pass the array to the called
// function
// function with ellipsis has ellipsis replaced by void* pointer
// use of va_list is turned into assignment of this pointer
// va_start is no-op, just like va_end
// va_arg returns casted memory at pointer and increments pointer afterwards by
// given size (+padding)
int add_em_up (int count,...)
{
va_list ap;
int i, sum;
va_start (ap, count); /* Initialize the argument list. */
sum = 0;
for (i = 0; i < count; i++)
sum += va_arg (ap, int); /* Get the next argument value. */
va_end (ap); /* Clean up. */
return sum;
}
int main (void)
{
/* This call prints 16. */
assert(16 == add_em_up (3, 5, 5, 6));
/* This call prints 55. */
assert(55 == add_em_up (10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10));
return 0;
}
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