What is ellipsis operator in c

Answer 1

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Answer 2

An ellipsis is used to represent a variable number of parameters to a function. For example:

void format(const char* fmt, ...)

The above function in C could then be called with different types and numbers of parameters such as:

format("%d-%d-%d", 2010, 9, 25);

and

format("product: %s, price: %f", "HDD", 450.90);

C99 introduced Variadic macros which also makes use of ellipsis.