C Tutorial/stdio.h/vprintf vfprintf vsprintf vsnprintf
vprintf, vfprintf, vsprintf, and vsnprintf
Item Value Header file stdarg.h stdio.h Declaration int vprintf(char *format, va_list arg_ptr); int vfprintf(FILE *stream, const char *format, va_list arg_ptr); int vsprintf(char *buf, const char *format, va_list arg_ptr); int vsnprintf(char * restrict buf, size_t num, const char * restrict format, va_list arg_ptr);
The functions vprintf(), vfprintf(), vsprintf(), and vsnprintf() are functionally equivalent to printf(), fprintf(), sprintf(), and snprintf(), respectively , except that the argument list has been replaced by a pointer to a list of arguments.
This pointer must be of type va_list, which is defined in the header <stdarg.h>.
#include <stdio.h>
#include <stdarg.h>
void print_message(char *format, ...)
{
va_list ptr;
va_start(ptr, format);
vprintf(format, ptr);
va_end(ptr);
}
int main(void)
{
print_message("Cannot open file %s.", "test");
return 0;
}