int vprintf(const char *format,
            __va_list arg);

vprintf writes to the standard output stream using putchar under control of the string pointed to by format that specifies how subsequent arguments are converted for output. Before calling vprintf, arg must be initialized by the va_start macro (and possibly subsequent va_arg calls). vprintf does not invoke the va_end macro.

vprintf returns the number of characters transmitted, or a negative value if an output or encoding error occurred.


vprintf is equivalent to printf with the variable argument list replaced by arg.