嵌入式 Linux当前系统时间转换为年月日以及星期几

int get_current_time(char *buf)
{
	struct tm *tmnow;
	struct timeval tv;
	gettimeofday(&tv,NULL);
	tmnow = localtime(&tv.tv_sec);
	
	sprintf(buf,"%04d/%02d/%02d %02d:%02d:%02d.%6d",\
		tmnow->tm_year+1900, tmnow->tm_mon+1, tmnow->tm_mday,tmnow->tm_hour,\
		tmnow->tm_min, tmnow->tm_sec,tv.tv_usec);	

	return tv.tv_sec;
}