The stdarg.h header defines a variable type va_list and
three macros which can be used to get the arguments in a function when
the number of arguments are not known i.e. variable number of arguments.
A function of variable arguments is defined with the ellipsis (,...) at the end of the parameter list.
A function of variable arguments is defined with the ellipsis (,...) at the end of the parameter list.
Library Variables
Following is the variable type defined in the header stdarg.h −| S.N. | Variable & Description |
|---|---|
| 1 |
va_list This is a type suitable for holding information needed by the three macros va_start(), va_arg() and va_end(). |
Library Macros
Following are the macros defined in the header stdarg.h −| S.N. | Macro & Description |
|---|---|
| 1 |
void va_start(va_list ap, last_arg) This macro initializes ap variable to be used with the va_arg and va_end macros. The last_arg is the last known fixed argument being passed to the function i.e. the argument before the ellipsis. |
| 2 |
type va_arg(va_list ap, type) This macro retrieves the next argument in the parameter list of the function with type type. |
| 3 |
void va_end(va_list ap) This macro allows a function with variable arguments which used the va_start macro to return. If va_end is not called before returning from the function, the result is undefined. |
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