自学教程：C++ GetCommState函数代码示例

}	void    WinSerial::setupLink(){        int     ret;        DCB     dcb = {0};        COMMTIMEOUTS cto = {10,10,10,10,10};        dcb.DCBlength = sizeof(DCB);        cto.ReadIntervalTimeout = 100;sprintf(logchunk, "opening com port <%s>/n", mDevName);log(logchunk);        mPortFh = CreateFile(mDevName, GENERIC_READ | GENERIC_WRITE,                                         0,                                         0,                                         OPEN_EXISTING,                                          0,                                         0                                         );   	if (mPortFh == INVALID_HANDLE_VALUE)    	{       		// Handle the error.       		printf ("CreateFile failed with error %ld./n", GetLastError());       		exit(1);   	}sprintf(logchunk, " port %d/n", mPortFh);log(logchunk);        assert(mPortFh);        ret = GetCommState(mPortFh, &dcb);        if (!ret)        {                fprintf(stderr, "GetCommState failed %d/n",                                 GetLastError());                exit(2);        }  //       dcb.BaudRate = CBR_57600;        dcb.BaudRate = CBR_256000;    	dcb.ByteSize    = 8;    	dcb.StopBits    = ONESTOPBIT;    	dcb.Parity      = NOPARITY;    	dcb.fDtrControl = DTR_CONTROL_DISABLE;    	dcb.fOutX       = FALSE;    	dcb.fInX        = FALSE;    	dcb.fNull       = FALSE;    	dcb.fRtsControl = RTS_CONTROL_DISABLE;// need to send binary data	dcb.fBinary = 1;//    *  fInX, fOutX,fOutXDsrFlow, fOutXCtsFlow are set to FALSE//    * fDtrControl is set to DTR_CONTROL_ENABLE//    * fRtsControl is set to RTS_CONTROL_ENABLE             ret = SetCommState(mPortFh, &dcb);        if (!ret)        {                fprintf(stderr, "SetCommState failed %d/n",                                GetLastError());                exit(3);        }        ret = SetCommTimeouts(mPortFh, &cto);        if (!ret)        {                fprintf(stderr, "SetCommTimeouts failed %d/n",                                GetLastError());                exit(3);        }	log("setup/n");	mSetup = 1;

int main(void){	/* I searched for this topic and found no real leads so i looked it up.	 * Opening the serial port	 * First point is to open a connection. Before opening any connection several informations must be acquired.	 * 	 * The name of the serial port.(Usually COM1-COM6 )	 * The direction of communication.	 * (It is possible to set the communication to an asynchronic mode but it is far mor complex and unintuitive than the synchronic mode used here)	 */	LPCSTR portname = "COM4";	DWORD  accessdirection =GENERIC_READ | GENERIC_WRITE;	HANDLE hSerial = CreateFile(portname,		accessdirection,		0,		0,		OPEN_EXISTING,		0,		0);	if (hSerial == INVALID_HANDLE_VALUE) {		//call GetLastError(); to gain more information		printf("Error 1/n");	}		/*	 * After opening the port further settings like Baudrate, Byte size, the number of stopbits and the Parity need to be set.	 */	 	DCB dcbSerialParams = {0};	dcbSerialParams.DCBlength=sizeof(dcbSerialParams);	if (!GetCommState(hSerial, &dcbSerialParams)) {		 //could not get the state of the comport	}	dcbSerialParams.BaudRate=9600;	dcbSerialParams.ByteSize=8;	dcbSerialParams.StopBits=ONESTOPBIT;	dcbSerialParams.Parity=NOPARITY;	if(!SetCommState(hSerial, &dcbSerialParams)){		 //analyse error		 printf("Error 2/n");	}			/* Finally timeouts need to be set so that the program does not hang up when receiving nothing. */	COMMTIMEOUTS timeouts={0};	timeouts.ReadIntervalTimeout=50;	timeouts.ReadTotalTimeoutConstant=50;	timeouts.ReadTotalTimeoutMultiplier=10;	timeouts.WriteTotalTimeoutConstant=50;	timeouts.WriteTotalTimeoutMultiplier=10;	if(!SetCommTimeouts(hSerial, &timeouts)){		//handle error		 printf("Error 3/n");    }		{		uint8_t symbol = 'A';		for(symbol = 'A'; symbol <= 'Z'; ++symbol){			(void)writeToSerialPort(hSerial, &symbol, 1);		}	}		/* Closing: when the serial port is not longer needed, it can be freed by closing the associated handle. */	CloseHandle(hSerial);		printf("Hello/n");		} /* main */

serial_source open_serial_source(const char *device, int baud_rate,				 int non_blocking,				 void (*message)(serial_source_msg problem))/* Effects: opens serial port device at specified baud_rate. If non_blocking     is true, read_serial_packet calls will be non-blocking (writes are     always blocking, for now at least)   Returns: descriptor for serial forwarder at host:port, or     NULL for failure (bad device or bad baud rate) */{#ifndef LOSE32  struct termios newtio;  int fd;  tcflag_t baudflag = parse_baudrate(baud_rate);  if (!baudflag)    return NULL;  fd = open(device, O_RDWR | O_NOCTTY | O_NONBLOCK);  if (fd < 0)    return NULL;  /* Serial port setting */  memset(&newtio, 0, sizeof(newtio));  newtio.c_cflag = CS8 | CLOCAL | CREAD;  newtio.c_iflag = IGNPAR | IGNBRK;  cfsetispeed(&newtio, baudflag);  cfsetospeed(&newtio, baudflag);  /* Raw output_file */  newtio.c_oflag = 0;  if (tcflush(fd, TCIFLUSH) >= 0 &&      tcsetattr(fd, TCSANOW, &newtio) >= 0)    {      serial_source src = malloc(sizeof *src);      if (src)	{	  memset(src, 0, sizeof *src);	  src->fd = fd;	  src->non_blocking = non_blocking;	  src->message = message;	  src->send.seqno = 37;	  return src;	}    }  close(fd);  return NULL;#else // LOSE32	LPCTSTR       ComName = (LPCTSTR)device;    HANDLE        hComm;	DCB           dcb;    serial_source src;	int buflen = MultiByteToWideChar(CP_ACP,0,(PCSTR)device,-1,(LPWSTR)ComName,0);	MultiByteToWideChar(CP_ACP,0,(PCSTR)device,-1,(LPWSTR)ComName,buflen);		//syncronize	hComm = CreateFile(ComName,  GENERIC_READ | GENERIC_WRITE,  0,  NULL,  OPEN_EXISTING,					FILE_ATTRIBUTE_NORMAL, NULL);    if (hComm == INVALID_HANDLE_VALUE) {        return NULL;    }    PurgeComm(hComm, PURGE_RXCLEAR);	GetCommState(hComm, &dcb); 	dcb.BaudRate = baud_rate;	dcb.ByteSize = 8;	dcb.Parity = NOPARITY;	dcb.fParity = FALSE;	dcb.StopBits = ONESTOPBIT;    if (SetCommState(hComm, &dcb) == 0) {        return NULL;    }    src = malloc(sizeof *src);    if (src) {	  memset(src, 0, sizeof *src);	  src->hComm = hComm;	  src->non_blocking = non_blocking;	  src->message = message;	  src->send.seqno = 37;	}	return src;#endif // LOSE32}

	int setAttributes(int baudRate, Parity parity, int dataBits, StopBits bits, Handshake hs, int readTimeout, int writeTimeout)	{		DCB dcb;		if (!GetCommState(this->handle, &dcb))		{			return GetLastError();		}		dcb.BaudRate = baudRate;		dcb.Parity = (byte)parity;		dcb.ByteSize = (byte)dataBits;        switch (bits)        {        case StopBits_10:            dcb.StopBits = ONESTOPBIT;            break;        case StopBits_15:            dcb.StopBits = ONE5STOPBITS;            break;        case StopBits_20:            dcb.StopBits = TWOSTOPBITS;            break;        default:            break;        }		// Clear Handshake flags		dcb.fOutxCtsFlow = 0;		dcb.fOutX = 0;		dcb.fInX = 0;		dcb.fRtsControl = 0;		// Set Handshake flags		switch (hs)		{		case Handshake_None:			break;		case Handshake_XonXoff:			dcb.fOutX = 1;			dcb.fInX = 1;			break;		case Handshake_RequestToSend:			dcb.fOutxCtsFlow = 1;			dcb.fRtsControl = 1;			break;		case Handshake_RequestToSendXonXoff:			dcb.fOutX = 1;			dcb.fInX = 1;			dcb.fOutxCtsFlow = 1;			dcb.fRtsControl = 1;			break;		default: // Shouldn't happen			break;		}		if (!SetCommState(handle, &dcb))		{			return GetLastError();		}		return S_OK;	}

void serialDriver::open(std::string com_port, long baud_rate, int databits, sdff_serial_paritymodes parity, double stopbits, sdff_serial_handshaking handshaking){    std::string par="NO_PARITY";    if (parity==sdffserEVEN) par="EVEN_PARITY";    if (parity==sdffserODD) par="ODD_PARITY";    std::string name="serialDriver::open(port="+com_port+", baud_rate="+inttostr(baud_rate)+", databits="+inttostr(databits)+", stopbits="+floattostr(stopbits)+" parity="+par+")";    if (ports.find(com_port)!=ports.end()) {        SEQUENCER_ERRORV(SEQUENCER_SERERROR_PORTALREADYOPEN_NUM, name, com_port.c_str());    }    BOOL fSuccess;    DCB dcb;      /* device control block */    BYTE StopBits;    if (stopbits==1) {        StopBits=ONESTOPBIT;    } else if (stopbits==1.5) {        StopBits=ONE5STOPBITS;    } else if (stopbits==2) {        StopBits=TWOSTOPBITS;    } else {        SEQUENCER_ERRORV(SEQUENCER_SERERROR_IMPOSSIBLEARG_NUM, name, com_port.c_str(), floattostr(stopbits).c_str(), "stop_bits", "1, 1.5, 2");    }    BYTE Parity=NOPARITY;    DWORD fParity;    if (parity==sdffserEVEN) {        Parity=EVENPARITY;        fParity=TRUE;    } else if (parity==sdffserODD) {        Parity=ODDPARITY;        fParity=TRUE;    } else if (parity==sdffserNOPARITY) {        Parity=NOPARITY;        fParity=FALSE;    }    ports[com_port] = CreateFileA(com_port.c_str(), GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, NULL);    if (ports[com_port]==INVALID_HANDLE_VALUE) {        ports.erase(com_port);        win32_error(name);    }    fSuccess = GetCommState(ports[com_port], &dcb);    if (!fSuccess) {        CloseHandle(ports[com_port]);        ports.erase(com_port);        win32_error(name);    }    /* configure the port */    dcb.BaudRate = baud_rate;    dcb.ByteSize = databits;    dcb.Parity = Parity;    dcb.StopBits = StopBits;    /* configure handshaking */	switch (handshaking) {	case sdffserNOHANDSHAKING:		dcb.fOutxCtsFlow = false;					// Disable CTS monitoring		dcb.fOutxDsrFlow = false;					// Disable DSR monitoring		dcb.fDtrControl = DTR_CONTROL_DISABLE;		// Disable DTR monitoring		dcb.fOutX = false;							// Disable XON/XOFF for transmission		dcb.fInX = false;							// Disable XON/XOFF for receiving		dcb.fRtsControl = RTS_CONTROL_DISABLE;		// Disable RTS (Ready To Send)		break;	case sdffserHARDWARE:		dcb.fOutxCtsFlow = true;					// Enable CTS monitoring		dcb.fOutxDsrFlow = true;					// Enable DSR monitoring		dcb.fDtrControl = DTR_CONTROL_HANDSHAKE;	// Enable DTR handshaking		dcb.fOutX = false;							// Disable XON/XOFF for transmission		dcb.fInX = false;							// Disable XON/XOFF for receiving		dcb.fRtsControl = RTS_CONTROL_HANDSHAKE;	// Enable RTS handshaking		break;	case sdffserXONXOFF:		dcb.fOutxCtsFlow = false;					// Disable CTS (Clear To Send)		dcb.fOutxDsrFlow = false;					// Disable DSR (Data Set Ready)		dcb.fDtrControl = DTR_CONTROL_DISABLE;		// Disable DTR (Data Terminal Ready)		dcb.fOutX = true;							// Enable XON/XOFF for transmission		dcb.fInX = true;							// Enable XON/XOFF for receiving		dcb.fRtsControl = RTS_CONTROL_DISABLE;		// Disable RTS (Ready To Send)		break;	}    fSuccess = SetCommState(ports[com_port], &dcb);    if (!fSuccess) {        CloseHandle(ports[com_port]);        ports.erase(com_port);        win32_error(name);    }    COMMTIMEOUTS commTimeout;    if(GetCommTimeouts(ports[com_port], &commTimeout))    {        commTimeout.ReadIntervalTimeout     = 500;        commTimeout.ReadTotalTimeoutConstant     = 100;        commTimeout.ReadTotalTimeoutMultiplier     = 500;        commTimeout.WriteTotalTimeoutConstant     = 100;        commTimeout.WriteTotalTimeoutMultiplier = 500;    } else {//.........这里部分代码省略.........

COMMNG cmserial_create(UINT port, UINT8 param, UINT32 speed) {	TCHAR	commstr[16];	HANDLE	hdl;	DCB		dcb;	UINT	i;	COMMNG	ret;	CMSER	serial;	wsprintf(commstr, _T("COM%u"), port);	hdl = CreateFile(commstr, GENERIC_READ | GENERIC_WRITE,												0, 0, OPEN_EXISTING, 0, NULL);	if (hdl == INVALID_HANDLE_VALUE) {		goto cscre_err1;	}	GetCommState(hdl, &dcb);	for (i=0; i<NELEMENTS(cmserial_speed); i++) {		if (cmserial_speed[i] >= speed) {			dcb.BaudRate = cmserial_speed[i];			break;		}	}	dcb.ByteSize = (UINT8)(((param >> 2) & 3) + 5);	switch(param & 0x30) {		case 0x10:			dcb.Parity = ODDPARITY;			break;		case 0x30:			dcb.Parity = EVENPARITY;			break;		default:			dcb.Parity = NOPARITY;			break;	}	switch(param & 0xc0) {		case 0x80:			dcb.StopBits = ONE5STOPBITS;			break;		case 0xc0:			dcb.StopBits = TWOSTOPBITS;			break;		default:			dcb.StopBits = ONESTOPBIT;			break;	}	SetCommState(hdl, &dcb);	ret = (COMMNG)_MALLOC(sizeof(_COMMNG) + sizeof(_CMSER), "SERIAL");	if (ret == NULL) {		goto cscre_err2;	}	ret->connect = COMCONNECT_MIDI;	ret->read = serialread;	ret->write = serialwrite;	ret->getstat = serialgetstat;	ret->msg = serialmsg;	ret->release = serialrelease;	serial = (CMSER)(ret + 1);	serial->hdl = hdl;	return(ret);cscre_err2:	CloseHandle(hdl);cscre_err1:	return(NULL);}

//////////////////////////////////////////////////////////////////////////////////////////// Open a communication channel to the given serial port name.XsensResultValue Cmt1s::open(  const char *portName,						const uint32_t baudRate,						uint32_t readBufSize,						uint32_t writeBufSize){	MRPT_UNUSED_PARAM(readBufSize); MRPT_UNUSED_PARAM(writeBufSize);	m_endTime = 0;	CMT1LOG("L1: Open port %s at %d baud/n", portName, baudRate);	if (m_isOpen)	{		CMT1LOG("L1: Port already open/n");		return (m_lastResult = XRV_ALREADYOPEN);	}	m_baudrate = baudRate;#ifdef _WIN32	char winPortName[32];	// Open port	sprintf(winPortName, "////.//%s", portName);	m_handle = CreateFileA(winPortName, GENERIC_READ | GENERIC_WRITE, 0, NULL,									OPEN_EXISTING, 0, NULL);	if (m_handle == INVALID_HANDLE_VALUE)	{		CMT1LOG("L1: Port cannot be opened/n");		return (m_lastResult = XRV_INPUTCANNOTBEOPENED);	}	// Once here, port is open	m_isOpen = true;	//Get the current state & then change it	GetCommState(m_handle, &m_commState);	// Get current state	m_commState.BaudRate = baudRate;			// Setup the baud rate	m_commState.Parity = NOPARITY;				// Setup the Parity	m_commState.ByteSize = 8;					// Setup the data bits	m_commState.StopBits = TWOSTOPBITS;			// Setup the stop bits	m_commState.fDsrSensitivity = FALSE;		// Setup the flow control	m_commState.fOutxCtsFlow = FALSE;			// NoFlowControl:	m_commState.fOutxDsrFlow = FALSE;	m_commState.fOutX = FALSE;	m_commState.fInX = FALSE;	if (!SetCommState(m_handle, (LPDCB)&m_commState)) {// Set new state		// Bluetooth ports cannot always be opened with 2 stopbits		// Now try to open port with 1 stopbit.		m_commState.StopBits = ONESTOPBIT;		if (!SetCommState(m_handle, (LPDCB)&m_commState)) {			CloseHandle(m_handle);			m_handle = INVALID_HANDLE_VALUE;			m_isOpen = false;			return (m_lastResult = XRV_INPUTCANNOTBEOPENED);		}	}	m_port = atoi(&portName[3]);	sprintf(m_portname, "%s", portName);	setTimeout(m_timeout);	// Other initialization functions	EscapeCommFunction(m_handle, SETRTS);		// Enable RTS (for Xbus Master use)	// Set DTR (Calibration sensors need DTR to startup, won't hurt otherwise	EscapeCommFunction(m_handle, SETDTR);	SetupComm(m_handle,readBufSize,writeBufSize);	// Set queue size	// Remove any 'old' data in buffer	//PurgeComm(m_handle, PURGE_TXCLEAR | PURGE_RXCLEAR);	PurgeComm(m_handle, PURGE_TXABORT | PURGE_RXABORT | PURGE_TXCLEAR | PURGE_RXCLEAR);#else // !_WIN32	// Open port	m_handle = ::open(portName, O_RDWR | O_NOCTTY);	// O_RDWR: Read+Write	// O_NOCTTY: Raw input, no "controlling terminal"	// O_NDELAY: Don't care about DCD signal	if (m_handle < 0) {		// Port not open		return m_lastResult = XRV_INPUTCANNOTBEOPENED;	}	// Once here, port is open	m_isOpen = true;	/* Start configuring of port for non-canonical transfer mode */	// Get current options for the port	tcgetattr(m_handle, &m_commState);	// Set baudrate.	cfsetispeed(&m_commState, baudRate);	cfsetospeed(&m_commState, baudRate);	// Enable the receiver and set local mode	m_commState.c_cflag |= (CLOCAL | CREAD);	// Set character size to data bits and set no parity Mask the characte size bits	m_commState.c_cflag &= ~(CSIZE|PARENB);	m_commState.c_cflag |= CS8;		// Select 8 data bits//.........这里部分代码省略.........

Serial::Serial(char *portName){    //We're not yet connected    this->connected = false;    //Try to connect to the given port through CreateFile    this->hSerial = CreateFile(portName,            GENERIC_READ | GENERIC_WRITE,            0,            NULL,            OPEN_EXISTING,            FILE_ATTRIBUTE_NORMAL,            NULL);    //Check if the connection was successfull    if(this->hSerial==INVALID_HANDLE_VALUE)    {        //If not successful display an Error        if(GetLastError()==ERROR_FILE_NOT_FOUND){            //Print Error if neccessary            printf("ERROR: Handle was not attached. Reason: %s not available./n", portName);        }        else        {            printf("ERROR!!!");        }    }    else    {        //If connected we try to set the comm parameters        DCB dcbSerialParams = {0};        //Try to get the current        if (!GetCommState(this->hSerial, &dcbSerialParams))        {            //If impossible, show an error            printf("failed to get current serial parameters!");        }        else        {            //Define serial connection parameters for the arduino board            dcbSerialParams.BaudRate=CBR_9600;            dcbSerialParams.ByteSize=8;            dcbSerialParams.StopBits=ONESTOPBIT;            dcbSerialParams.Parity=NOPARITY;             //Set the parameters and check for their proper application             if(!SetCommState(hSerial, &dcbSerialParams))             {                printf("ALERT: Could not set Serial Port parameters");             }             else             {                 //If everything went fine we're connected                 this->connected = true;                 //We wait 2s as the arduino board will be reseting                 Sleep(ARDUINO_WAIT_TIME);             }        }    }}

/*打开串口*/HANDLE CComInit::OpenComm(int ncom){	memset( &m_read_os, 0, sizeof( OVERLAPPED ) ) ;    	memset( &m_write_os, 0, sizeof( OVERLAPPED ) ) ;		CString Com;	Com.Format(_T("COM%d"),ncom);	HANDLE hCom = CreateFile(Com,GENERIC_READ | GENERIC_WRITE,		0,NULL,OPEN_EXISTING,FILE_FLAG_OVERLAPPED,NULL);	if(INVALID_HANDLE_VALUE==hCom)	{		CloseHandle(hCom);		return hCom;	}	//创建事件	m_read_os.hEvent = CreateEvent(NULL,TRUE,FALSE,NULL);	m_write_os.hEvent = CreateEvent(NULL,TRUE,FALSE,NULL);	if(NULL == m_read_os.hEvent || NULL == m_write_os.hEvent){		CloseHandle(hCom);		CloseHandle(m_read_os.hEvent);		CloseHandle(m_write_os.hEvent);		hCom = INVALID_HANDLE_VALUE;		return hCom;	}	//设置com事件类型，参见msdn	SetCommMask(hCom,EV_RXCHAR | EV_TXEMPTY);	SetupComm( hCom, 1024,512 );//设置缓冲区大小;	PurgeComm( hCom, PURGE_TXABORT | PURGE_RXABORT | PURGE_TXCLEAR		| PURGE_RXCLEAR ); //清干净输入、输出缓冲区	DCB dcb={0};	dcb.DCBlength=sizeof(dcb);	BOOL bres=GetCommState(hCom,&dcb);	if(!bres)	{		CloseHandle(hCom);		hCom=INVALID_HANDLE_VALUE;		return hCom;	}	dcb.ByteSize=8;//后改	dcb.fParity=0;	dcb.BaudRate=CBR_9600;	dcb.StopBits=ONESTOPBIT;	bres=SetCommState(hCom,&dcb);	if(!bres)	{		CloseHandle(hCom);		hCom=INVALID_HANDLE_VALUE;		return hCom;	}	COMMTIMEOUTS comm_time={0};	comm_time.ReadIntervalTimeout=MAXDWORD;	bres=SetCommTimeouts(hCom,&comm_time);//	SetupComm(m_hComWndScreen, 4096, 1024);	if(!bres)	{		CloseHandle(hCom);		CloseHandle(m_read_os.hEvent);		CloseHandle(m_write_os.hEvent);		hCom = INVALID_HANDLE_VALUE;		return hCom;	}	return hCom;}

static co_rc_t coserial_main(int argc, char *argv[]){	co_rc_t rc;	co_module_t module;	HANDLE out_handle, in_handle;	int select_time;	rc = handle_parameters(&g_daemon_parameters, argc, argv);	if (!CO_OK(rc))		return rc;	rc = co_reactor_create(&g_reactor);	if (!CO_OK(rc))		return rc;	co_debug("connecting to monitor");	module = CO_MODULE_SERIAL0 + g_daemon_parameters.index;	rc = co_user_monitor_open(g_reactor, monitor_receive,				  g_daemon_parameters.instance,				  &module, 1,				  &g_monitor_handle);	if (!CO_OK(rc))		return rc;	if (g_daemon_parameters.filename_specified == PTRUE) {		char name [strlen(g_daemon_parameters.filename) + 4+1];		DCB dcb;		COMMTIMEOUTS commtimeouts = {			1,	/* ReadIntervalTimeout */			0,	/* ReadTotalTimeoutMultiplier */			0,	/* ReadTotalTimeoutConstant */			0,	/* WriteTotalTimeoutMultiplier */			0 };	/* WriteTotalTimeoutConstant */		if (g_daemon_parameters.filename[0] != '//') {			/* short windows name */			if (strncasecmp(g_daemon_parameters.filename, "COM", 3) != 0)				co_terminal_print("warning: host serial device '%s' is not a COM port/n",						    g_daemon_parameters.filename);			snprintf(name, sizeof(name), "////.//%s", g_daemon_parameters.filename);		} else {			/* windows full name device */			strncpy(name, g_daemon_parameters.filename, sizeof(name));		}		co_debug("open device '%s'", name);		out_handle = /		in_handle = CreateFile (name,				GENERIC_READ | GENERIC_WRITE, 0, NULL,				OPEN_EXISTING,				FILE_ATTRIBUTE_NORMAL | FILE_FLAG_OVERLAPPED, NULL);		if (in_handle == INVALID_HANDLE_VALUE) {			co_terminal_print_last_error(g_daemon_parameters.filename);			return CO_RC(ERROR);		}		if (g_daemon_parameters.mode_specified == PTRUE) {			co_debug("set mode: %s", g_daemon_parameters.mode);			if (!GetCommState(in_handle, &dcb)) {				co_terminal_print_last_error("GetCommState");				return CO_RC(ERROR);			}			/* Set defaults. user can overwrite ot */			dcb.fOutxCtsFlow = FALSE; /* Disable Handshake */			dcb.fDtrControl = DTR_CONTROL_ENABLE;			dcb.fRtsControl = RTS_CONTROL_ENABLE;			if (!BuildCommDCB(g_daemon_parameters.mode, &dcb)) {				/*co_terminal_print_last_error("colinux-serial-daemon: BuildCommDCB");*/				co_terminal_print("colinux-serial-daemon: error in mode parameter '%s'/n",							g_daemon_parameters.mode);				return CO_RC(ERROR);			}			if (!SetCommState(in_handle, &dcb)) {				co_terminal_print_last_error("SetCommState");				return CO_RC(ERROR);			}		} else {			if (!EscapeCommFunction(in_handle, SETDTR)) {				co_terminal_print_last_error("Warning EscapeCommFunction DTR");				/* return CO_RC(ERROR); */			}			if (!EscapeCommFunction(in_handle, SETRTS)) {				co_terminal_print_last_error("Warning EscapeCommFunction RTS");				/* return CO_RC(ERROR); */			}		}		if (!SetCommTimeouts(in_handle, &commtimeouts)) {			co_terminal_print_last_error("SetCommTimeouts");			return CO_RC(ERROR);		}		if (!SetupComm(in_handle, 2048, 2048)) {			co_terminal_print_last_error("SetupComm");//.........这里部分代码省略.........

bool PrinterSerial::RawConnect( string device, int baudrate ) {#ifdef WIN32  if ( IsConnected() || device_handle != INVALID_HANDLE_VALUE ) {    Disconnect();    if ( device_handle != INVALID_HANDLE_VALUE )      return false;  }  device_handle = CreateFile( device.c_str(),			      GENERIC_READ | GENERIC_WRITE,			      0,			      NULL,			      OPEN_EXISTING,			      FILE_ATTRIBUTE_NORMAL,			      NULL );  if ( device_handle == INVALID_HANDLE_VALUE ) {    char err_str[ 256 ];    snprintf( err_str, 256, _("Error opening port %s"), device.c_str() );    err_str[ 256 ] = '/0';    ostringstream os;    os << err_str << " (" << GetLastError() << ")"<< endl;    LogError( os.str().c_str() );    return false;  }  DCB dcb = { 0 };  dcb.DCBlength = sizeof( dcb );  if ( ! GetCommState( device_handle, &dcb ) ) {    CloseHandle( device_handle );    device_handle = INVALID_HANDLE_VALUE;    char err_str[ 256 ];    snprintf( err_str, 256, _("Error getting port %s state"), device.c_str() );    err_str[ 255 ] = '/0';    ostringstream os;    os << err_str << " (" << GetLastError() << ")"<< endl;    LogError( os.str().c_str() );    return false;  }  dcb.BaudRate = baudrate;  dcb.fBinary = 1;  dcb.fParity = 0;  dcb.fOutxCtsFlow = 0;  dcb.fOutxDsrFlow = 0;  dcb.fDtrControl = DTR_CONTROL_ENABLE;  dcb.fDsrSensitivity = 0;  dcb.fOutX = 0;  dcb.fInX = 0;  dcb.fNull = 0;  dcb.fRtsControl = RTS_CONTROL_ENABLE;  dcb.ByteSize = 8;  dcb.Parity = NOPARITY;  dcb.StopBits = ONESTOPBIT;  if ( ! SetCommState( device_handle, &dcb ) ) {    CloseHandle( device_handle );    device_handle = INVALID_HANDLE_VALUE;    char err_str[ 256 ];    snprintf( err_str, 256, _("Error setting port %s state"), device.c_str() );    err_str[ 255 ] = '/0';    ostringstream os;    os << err_str << " (" << GetLastError() << ")"<< endl;    LogError( os.str().c_str() );    return false;  }  COMMTIMEOUTS ct;  if ( ! GetCommTimeouts( device_handle, &ct ) ) {    CloseHandle( device_handle );    device_handle = INVALID_HANDLE_VALUE;    char err_str[ 256 ];    snprintf( err_str, 256, _("Error getting port %s timeouts"), device.c_str() );    err_str[ 255 ] = '/0';    ostringstream os;    os << err_str << " (" << GetLastError() << ")"<< endl;    LogError( os.str().c_str() );    return false;  }  ct.ReadIntervalTimeout = 5;  ct.ReadTotalTimeoutConstant = max_recv_block_ms;  ct.ReadTotalTimeoutMultiplier = 0;  ct.WriteTotalTimeoutConstant = max_recv_block_ms;  ct.WriteTotalTimeoutMultiplier= 0;  if ( ! SetCommTimeouts( device_handle, &ct ) ) {    CloseHandle( device_handle );    device_handle = INVALID_HANDLE_VALUE;    char err_str[ 256 ];    snprintf( err_str, 256, _("Error setting port %s timeouts"), device.c_str() );    err_str[ 255 ] = '/0';    ostringstream os;    os << err_str << " (" << GetLastError() << ")"<< endl;    LogError( os.str().c_str() );//.........这里部分代码省略.........

BOOL SerialOpen(int port, int baud) {	HANDLE Comport;	DCB myDCB;	COMMTIMEOUTS CTout;	char str[100];	if (port > 9)		sprintf(str, "////.//COM%d", port);	else		sprintf(str, "COM%d", port);	// Open the serial port	if ((Comport = CreateFile(str, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, NULL)) == INVALID_HANDLE_VALUE)		return FALSE;	// Configure Serial port (Setup Comm)	// Buffer sizes	if (!SetupComm(Comport, 128, 128))		return FALSE;	// Setup DCB using current values	if (!GetCommState(Comport, &myDCB))		return FALSE;	myDCB.fInX = FALSE;     // Turn off xon/xoff handler	myDCB.fOutX = FALSE;	myDCB.fOutxDsrFlow = FALSE;	myDCB.fOutxCtsFlow = FALSE;    // no hardware flow control.	myDCB.BaudRate = baud;	myDCB.DCBlength = sizeof(DCB);	myDCB.fBinary = 1;	myDCB.fParity = 0;	myDCB.fDtrControl = DTR_CONTROL_DISABLE;	myDCB.fDsrSensitivity = 0;	myDCB.fTXContinueOnXoff = 1;	myDCB.fNull = 0;	myDCB.fRtsControl = RTS_CONTROL_DISABLE;	myDCB.fDummy2 = 0;	myDCB.wReserved = 0;	myDCB.Parity = NOPARITY;	myDCB.StopBits = ONESTOPBIT;	myDCB.wReserved1 = 0;	myDCB.ByteSize = 8;	if (!SetCommState(Comport, &myDCB))		return FALSE;	// Set timeouts	CTout.ReadIntervalTimeout = 0xffffffff;	CTout.ReadTotalTimeoutMultiplier = 0;	CTout.ReadTotalTimeoutConstant = 0;	CTout.WriteTotalTimeoutMultiplier = 0;	CTout.WriteTotalTimeoutConstant = 5000;         // don't hang if CTS is locked, for example	SetCommTimeouts(Comport, &CTout);	EscapeCommFunction(Comport, SETDTR);	PurgeComm(Comport, PURGE_TXCLEAR | PURGE_RXCLEAR);	SerialPort = Comport;	return TRUE;}

// 打开串口HANDLE CMySerialPort::OpenPort(){    if (IsOpen())    {        return m_portHandle;    }    if (0 >= m_strComName.GetLength())    {        LOG.err_log("请先设置串口参数");        CString strTip = "请先设置串口参数";        SHOWTIP(strTip);        return INVALID_HANDLE_VALUE;    }    // 以重叠方式打开串口    m_strComName = "////.//" + m_strComName;    m_portHandle = CreateFile(m_strComName,        GENERIC_READ|GENERIC_WRITE,        0,        NULL,        OPEN_EXISTING,        0, //FILE_ATTRIBUTE_NORMAL|FILE_FLAG_OVERLAPPED,        NULL);    if (INVALID_HANDLE_VALUE == m_portHandle)    {        CString strTip;        LOG.err_log("打开串口[%s]失败", (LPCSTR)m_strComName);        strTip.Format("打开串口[%s]失败", m_strComName);        SHOWTIP(strTip);        return INVALID_HANDLE_VALUE;    }    // 设置串口参数    DCB dcb;    BOOL ret = GetCommState(m_portHandle, &dcb);    if (FALSE == ret)    {        LOG.err_log("获取串口默认配置参数失败");        CString strTip("获取串口默认配置参数失败");        SHOWTIP(strTip);        return INVALID_HANDLE_VALUE;    }    dcb.BaudRate = m_baud;    dcb.StopBits = m_stopbits;    dcb.Parity = m_check;    dcb.ByteSize = m_databits;    //dcb.fParity = FALSE; // 禁止奇偶检查    //dcb.fBinary = TRUE;//是否允许传二进制     if (FALSE == SetCommState(m_portHandle,&dcb))    {        LOG.err_log("配置串口参数失败!");        CString strTip("配置串口参数失败!");        SHOWTIP(strTip);        return INVALID_HANDLE_VALUE;    }        // 设置缓冲区大小    if (FALSE == SetupComm(m_portHandle, 1024, 1024))    {        LOG.err_log("缓冲区设置失败!");        CString strTip("缓冲区设置失败!");        SHOWTIP(strTip);        return INVALID_HANDLE_VALUE;    }    // 设置串口超时时间    COMMTIMEOUTS CommTimeOuts;    CommTimeOuts.ReadIntervalTimeout = 100;    CommTimeOuts.ReadTotalTimeoutMultiplier = 100;    CommTimeOuts.ReadTotalTimeoutConstant = 100;    CommTimeOuts.WriteTotalTimeoutMultiplier = 500;    CommTimeOuts.WriteTotalTimeoutConstant = 2000;    if(false == SetCommTimeouts(m_portHandle,&CommTimeOuts))    {        LOG.err_log("设置读写超时时间失败!");        CString strTip("设置读写超时时间失败!");        SHOWTIP(strTip);        return INVALID_HANDLE_VALUE;    }    // 清空发送和接收缓冲区    PurgeComm(m_portHandle, PURGE_TXCLEAR|PURGE_RXCLEAR);    m_bClosePort = false;    return m_portHandle;}

//open//	Opens the serial port using stored information//	Sets the baud rate to the stored baud rate//	8 data bits, no parity, one stop bitbool serial_port::serial_open(){    printf("SerialPort: Opening serial port %s at baud rate %d./n", port_name, baud_rate);#ifdef WINDOWS    file_descriptor = CreateFile(port_name, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, NULL);    if((int)file_descriptor < 0)    {        printf("SerialPort: Port %s could not be opened: %d./n", port_name, file_descriptor);        return false;    }    SetupComm(file_descriptor, 1, 128);    GetCommState(file_descriptor, &dcb);    dcb.BaudRate = baud_rate;                   //Set baud rate    dcb.ByteSize = 8;                           //8 data bits    dcb.Parity = NOPARITY;                      //Parity = none    dcb.StopBits = ONESTOPBIT;                  //One stop bit    dcb.fAbortOnError = TRUE;                   //Abort on error    dcb.fOutX = FALSE;                          //XON/XOFF off for transmit    dcb.fInX = FALSE;                           //XON/XOFF off for receive    dcb.fOutxCtsFlow = FALSE;                   //Turn off CTS flow control    dcb.fRtsControl = RTS_CONTROL_DISABLE;      //Options DISABLE, ENABLE, HANDSHAKE    dcb.fOutxDsrFlow = FALSE;                   //Turn off DSR flow control    dcb.fDtrControl = DTR_CONTROL_DISABLE;      //Disable DTR control    SetCommState(file_descriptor, &dcb);    COMMTIMEOUTS timeouts = {0};    timeouts.ReadIntervalTimeout = 50;    timeouts.ReadTotalTimeoutConstant=50;    timeouts.ReadTotalTimeoutMultiplier=10;    timeouts.WriteTotalTimeoutConstant=50;    timeouts.WriteTotalTimeoutMultiplier=10;    SetCommTimeouts(file_descriptor, &timeouts);#endif#ifdef LINUX    file_descriptor = open(port_name, O_RDWR | O_NOCTTY | O_NDELAY);    if(file_descriptor < 0)    {        printf("SerialPort: Port %s could not be opened: %d./n", port_name, file_descriptor);        return false;    }    serial_struct ss;    ioctl(file_descriptor, TIOCGSERIAL, &ss);    ss.flags = (ss.flags & ~ASYNC_SPD_MASK) | ASYNC_SPD_CUST | ASYNCB_LOW_LATENCY;    ss.custom_divisor = (ss.baud_base + (baud_rate / 2)) / baud_rate;    int closestSpeed = ss.baud_base / ss.custom_divisor;    if((float)closestSpeed < ((float)baud_rate * (98.0f/100.0f)) || (float)closestSpeed > ((float)baud_rate * (102.0f/100.0f)))    {        printf("SerialPort: Cannot set %s to %d.  Closest possible speed is %d./n", port_name, baud_rate, closestSpeed);    }    else    {        printf("SerialPort: %s speed set to %d./n", port_name, baud_rate);    }    fcntl(file_descriptor, F_SETFL, 0);#endif    printf("SerialPort: Serial port %s opened successfully./n", port_name);    return true;}

ATMO_BOOL CAtmoClassicConnection::OpenConnection() {#if defined(_ATMO_VLC_PLUGIN_)     char *serdevice = m_pAtmoConfig->getSerialDevice();     if(!serdevice)        return ATMO_FALSE;#else     int portNummer = m_pAtmoConfig->getComport();     m_dwLastWin32Error = 0;	 if(portNummer < 1) return ATMO_FALSE; // make no real sense;-)#endif	 CloseConnection();#if !defined(_ATMO_VLC_PLUGIN_)     char serdevice[16];  // com4294967295     sprintf(serdevice,"com%d",portNummer);#endif#if defined(WIN32)     m_hComport = CreateFile(serdevice, GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, NULL);     if(m_hComport == INVALID_HANDLE_VALUE) {//      we have a problem here can't open com port... somebody else may use it?//	    m_dwLastWin32Error = GetLastError();	    return ATMO_FALSE;     }     /* change serial settings (Speed, stopbits etc.) */     DCB dcb; // für comport-parameter     dcb.DCBlength = sizeof(DCB);     GetCommState (m_hComport, &dcb); // ger current serialport settings     dcb.BaudRate  = 38400;        // set speed     dcb.ByteSize  = 8;            // set databits     dcb.Parity    = NOPARITY;     // set parity     dcb.StopBits  = ONESTOPBIT;   // set one stop bit     SetCommState (m_hComport, &dcb);    // apply settings#else     int bconst = B38400;     m_hComport = open(serdevice,O_RDWR |O_NOCTTY);     if(m_hComport < 0) {	    return ATMO_FALSE;     }     struct termios tio;     memset(&tio,0,sizeof(tio));     tio.c_cflag = (CS8 | CREAD | HUPCL | CLOCAL);     tio.c_iflag = (INPCK | BRKINT);     cfsetispeed(&tio, bconst);     cfsetospeed(&tio, bconst);     if(!tcsetattr(m_hComport, TCSANOW, &tio)) {         tcflush(m_hComport, TCIOFLUSH);     } else {         // can't change parms        close(m_hComport);        m_hComport = -1;        return false;     }#endif     return true;}

bool SerialPort::Initialize() {    TCHAR sysPortName[20];    DCB PortDCB;#if (WINDOWSPC>0)    // Do not use COMn , use //./COMnn  on PC version    _stprintf(sysPortName, _T("////.//%s"), GetPortName());#else    // Do not use COMn , use COMn:  on WinCE version    _stprintf(sysPortName, _T("%s:"), GetPortName());#endif    StartupStore(_T(". ComPort %u Initialize <%s> speed=%u bit=%u %s"),GetPortIndex()+1,GetPortName(),_dwPortSpeed,8-_dwPortBit,NEWLINE);    hPort = CreateFile(sysPortName, // Pointer to the name of the port            GENERIC_READ | GENERIC_WRITE, // Access (read-write) mode            0, // Share mode            NULL, // Pointer to the security attribute            OPEN_EXISTING, // How to open the serial port            FILE_ATTRIBUTE_NORMAL, // Port attributes            NULL); // Handle to port with attribute    // to copy    if (hPort == INVALID_HANDLE_VALUE) {        DWORD dwError = GetLastError();        StartupStore(_T("... ComPort %u Init failed, error=%u%s"), GetPortIndex() + 1, dwError, NEWLINE); // 091117        StatusMessage(MB_OK, NULL, TEXT("%s %s"), gettext(TEXT("[email
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