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Point out the error in the following program. #include #include int main() { void display(char s, int num1, int num2, ...); display("Hello", 4, 2, 12.5, 13.5, 14.5, 44.0); return 0; } void display(char s, int num1, int num2, ...) { double c; char s; va_list ptr; va_start(ptr, s); c = va_arg(ptr, double); printf("%f", c); }

Q: Point out the error in the following program. #include #include int main() { void display(char *s, int num1, int num2, ...); display("Hello", 4, 2, 12.5, 13.5, 14.5, 44.0); return 0; } void display(char *s, int num1, …

We should have use va_start(ptr, num2);

Error: invalid arguments in function display()
Error: too many parameters
Error: in va_start(ptr, s);
No error

Correct Answer: Error: in va_start(ptr, s);

Explanation:

We should have use va_start(ptr, num2);

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The macro va_start is used to initialise a pointer to the beginning of the list of fixed arguments.
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The macro va_arg is used to extract an argument from the variable argument list and advance the pointer to the next argument.
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