Something

void log_write(unsigned long log, char *msg, ...)
{
	va_list argptr;
	char *string, buf[MAX_BUFFER];
	string = malloc(MAX_BUFFER);
	va_start(argptr, msg);
	vsprintf(string, msg, argptr);
	va_end(argptr);

	strftime(buf, MAX_BUFFER, "%D %T", localtime(&now));
	printf("[%s] %s\n", buf, string);
	free(string);
}