readLine problem

**gQt** · 26th February 2008, 12:45

Hi,

I have a problem with the readLine function. It doesn't work while the computer is connected to the server. I have checked that the computer is connected with the telnet command. I have modified the Fortune Client example, removed the readFortune-function and added a readLine() in the requestNewFortune function. The last function is renamed to read_data(). I have also added a waitforConnected if test and a canReadLine if test before the readLine() and after the connectToHost. The canReadLine fails for some reason. I have also tried to remove the canReadLine but the readLine doesn't read anything (the output of mystring is empty). The program consists of three files: client.cpp, client.h, main.cpp

Any suggestions appreciated, thanks!

Regards
gQt

client.cpp

Qt Code:

Switch view

#include <QtGui>
#include <QtNetwork>
#include "client.h"
#include <iostream.h>
#include <QtCore>    
#include <qdebug.h>
Client::Client(QWidget *parent)
        : QDialog(parent)
    {
        hostLabel = new QLabel(tr("&Server name:"));
        portLabel = new QLabel(tr("S&erver port:"));
	hostLineEdit = new QLineEdit("10.249.0.48");
        portLineEdit = new QLineEdit("4007");
        portLineEdit->setValidator(new QIntValidator(1, 65535, this));
 
        hostLabel->setBuddy(hostLineEdit);
        portLabel->setBuddy(portLineEdit);
	statusLabel = new QLabel(tr("This examples requires that you run the "
                                    "Fortune Server example as well."));
 
        getFortuneButton = new QPushButton(tr("Get Fortune"));
        getFortuneButton->setDefault(true);
        getFortuneButton->setEnabled(false);
 
        quitButton = new QPushButton(tr("Quit"));
 
        tcpSocket = new QTcpSocket(this);
 
        connect(hostLineEdit, SIGNAL(textChanged(const QString &)),
                this, SLOT(enableGetFortuneButton()));
        connect(portLineEdit, SIGNAL(textChanged(const QString &)),
                this, SLOT(enableGetFortuneButton()));
        connect(getFortuneButton, SIGNAL(clicked()),
                this, SLOT(read_data()));
        connect(quitButton, SIGNAL(clicked()), this, SLOT(close()));
       	connect(tcpSocket, SIGNAL(readyRead()), this, SLOT(read_data()));
	connect(tcpSocket, SIGNAL(error(QAbstractSocket::SocketError)), this, SLOT(displayError(QAbstractSocket::SocketError)));
 
        QHBoxLayout *buttonLayout = new QHBoxLayout;
        buttonLayout->addStretch(1);
        buttonLayout->addWidget(getFortuneButton);
        buttonLayout->addWidget(quitButton);
 
        QGridLayout *mainLayout = new QGridLayout;
        mainLayout->addWidget(hostLabel, 0, 0);
        mainLayout->addWidget(hostLineEdit, 0, 1);
        mainLayout->addWidget(portLabel, 1, 0);
        mainLayout->addWidget(portLineEdit, 1, 1);
       	mainLayout->addWidget(statusLabel, 2, 0, 1, 2);
        mainLayout->addLayout(buttonLayout, 3, 0, 1, 2);
        setLayout(mainLayout);
 
        setWindowTitle(tr("Fortune Client"));
        portLineEdit->setFocus();
    }
 
    void Client::read_data()
    {
	getFortuneButton->setEnabled(true);
	tcpSocket->abort();
        tcpSocket->connectToHost(hostLineEdit->text(),
                                 portLineEdit->text().toInt());
 
	cout << ("fÃ¸r if(canReadLine)\n");
 
 	if(tcpSocket->waitForConnected(-1))
	{
		cout <<"wait for connected loop";		
		if(tcpSocket->canReadLine())
		{
	      	 	tcpSocket->readLine();
			qDebug() << "READ" << mystring;
			cout <<"canReadLine loop";	
		}	
		statusLabel->setText(mystring);
       		getFortuneButton->setEnabled(false);     
     	}
 
    }
    void Client::displayError(QAbstractSocket::SocketError socketError)
    {
        switch (socketError) {
        case QAbstractSocket::RemoteHostClosedError:
            break;
        case QAbstractSocket::HostNotFoundError:
            QMessageBox::information(this, tr("Fortune Client"),
                                     tr("The host was not found. Please check the "
                                        "host name and port settings."));
            break;
        case QAbstractSocket::ConnectionRefusedError:
            QMessageBox::information(this, tr("Fortune Client"),
                                     tr("The connection was refused by the peer. "
                                        "Make sure the fortune server is running, "
                                        "and check that the host name and port "
                                        "settings are correct."));
            break;
        default:
            QMessageBox::information(this, tr("Fortune Client"),
                                     tr("The following error occurred: %1.")
                                     .arg(tcpSocket->errorString()));
        }
 
        getFortuneButton->setEnabled(true);
    }
 
    void Client::enableGetFortuneButton()
    {
        getFortuneButton->setEnabled(!hostLineEdit->text().isEmpty()
                                     && !portLineEdit->text().isEmpty());
    }

#include <QtGui>
#include <QtNetwork>
#include "client.h"
#include <iostream.h>
#include <QtCore>    
#include <qdebug.h>
Client::Client(QWidget *parent)
        : QDialog(parent)
    {
        hostLabel = new QLabel(tr("&Server name:"));
        portLabel = new QLabel(tr("S&erver port:"));
	hostLineEdit = new QLineEdit("10.249.0.48");
        portLineEdit = new QLineEdit("4007");
        portLineEdit->setValidator(new QIntValidator(1, 65535, this));

        hostLabel->setBuddy(hostLineEdit);
        portLabel->setBuddy(portLineEdit);
	statusLabel = new QLabel(tr("This examples requires that you run the "
                                    "Fortune Server example as well."));

        getFortuneButton = new QPushButton(tr("Get Fortune"));
        getFortuneButton->setDefault(true);
        getFortuneButton->setEnabled(false);

        quitButton = new QPushButton(tr("Quit"));

        tcpSocket = new QTcpSocket(this);

        connect(hostLineEdit, SIGNAL(textChanged(const QString &)),
                this, SLOT(enableGetFortuneButton()));
        connect(portLineEdit, SIGNAL(textChanged(const QString &)),
                this, SLOT(enableGetFortuneButton()));
        connect(getFortuneButton, SIGNAL(clicked()),
                this, SLOT(read_data()));
        connect(quitButton, SIGNAL(clicked()), this, SLOT(close()));
       	connect(tcpSocket, SIGNAL(readyRead()), this, SLOT(read_data()));
	connect(tcpSocket, SIGNAL(error(QAbstractSocket::SocketError)), this, SLOT(displayError(QAbstractSocket::SocketError)));

        QHBoxLayout *buttonLayout = new QHBoxLayout;
        buttonLayout->addStretch(1);
        buttonLayout->addWidget(getFortuneButton);
        buttonLayout->addWidget(quitButton);
	
        QGridLayout *mainLayout = new QGridLayout;
        mainLayout->addWidget(hostLabel, 0, 0);
        mainLayout->addWidget(hostLineEdit, 0, 1);
        mainLayout->addWidget(portLabel, 1, 0);
        mainLayout->addWidget(portLineEdit, 1, 1);
       	mainLayout->addWidget(statusLabel, 2, 0, 1, 2);
        mainLayout->addLayout(buttonLayout, 3, 0, 1, 2);
        setLayout(mainLayout);

        setWindowTitle(tr("Fortune Client"));
        portLineEdit->setFocus();
    }

    void Client::read_data()
    {
	getFortuneButton->setEnabled(true);
	tcpSocket->abort();
        tcpSocket->connectToHost(hostLineEdit->text(),
                                 portLineEdit->text().toInt());
	   	
	cout << ("fÃ¸r if(canReadLine)\n");
	
 	if(tcpSocket->waitForConnected(-1))
	{
		cout <<"wait for connected loop";		
		if(tcpSocket->canReadLine())
		{
	      	 	tcpSocket->readLine();
			qDebug() << "READ" << mystring;
			cout <<"canReadLine loop";	
		}	
		statusLabel->setText(mystring);
       		getFortuneButton->setEnabled(false);     
     	}

    }
    void Client::displayError(QAbstractSocket::SocketError socketError)
    {
        switch (socketError) {
        case QAbstractSocket::RemoteHostClosedError:
            break;
        case QAbstractSocket::HostNotFoundError:
            QMessageBox::information(this, tr("Fortune Client"),
                                     tr("The host was not found. Please check the "
                                        "host name and port settings."));
            break;
        case QAbstractSocket::ConnectionRefusedError:
            QMessageBox::information(this, tr("Fortune Client"),
                                     tr("The connection was refused by the peer. "
                                        "Make sure the fortune server is running, "
                                        "and check that the host name and port "
                                        "settings are correct."));
            break;
        default:
            QMessageBox::information(this, tr("Fortune Client"),
                                     tr("The following error occurred: %1.")
                                     .arg(tcpSocket->errorString()));
        }

        getFortuneButton->setEnabled(true);
    }

    void Client::enableGetFortuneButton()
    {
        getFortuneButton->setEnabled(!hostLineEdit->text().isEmpty()
                                     && !portLineEdit->text().isEmpty());
    }

To copy to clipboard, switch view to plain text mode

client.h

Qt Code:

Switch view

#ifndef CLIENT_H
#define CLIENT_H
#include <QDialog>
#include <QTcpSocket>
#include <QAbstractSocket>
 
 class QDialogButtonBox;
 class QLabel;
 class QLineEdit;
 class QPushButton;
 class QTcpSocket;
 class Client : public QDialog
 {
   Q_OBJECT
 
 public:
     Client(QWidget *parent = 0);
 
 private slots:
     void read_data();
     void displayError(QAbstractSocket::SocketError socketError);
     void enableGetFortuneButton();
 
 private:
     QLabel *hostLabel;
     QLabel *portLabel;
     QLabel *cLabel;
     QLineEdit *hostLineEdit;
     QLineEdit *portLineEdit;
     QLabel *statusLabel;
     QPushButton *getFortuneButton;
     QPushButton *quitButton;
     QDialogButtonBox *buttonBox;
 
     QTcpSocket *tcpSocket;
     QTcpSocket tcpSocket2;
     QString currentFortune;
     QString mystring;
     quint16 blockSize;
 
};
 
#endif

#ifndef CLIENT_H
#define CLIENT_H
#include <QDialog>
#include <QTcpSocket>
#include <QAbstractSocket>
 
 class QDialogButtonBox;
 class QLabel;
 class QLineEdit;
 class QPushButton;
 class QTcpSocket;
 class Client : public QDialog
 {
   Q_OBJECT

 public:
     Client(QWidget *parent = 0);

 private slots:
     void read_data();
     void displayError(QAbstractSocket::SocketError socketError);
     void enableGetFortuneButton();

 private:
     QLabel *hostLabel;
     QLabel *portLabel;
     QLabel *cLabel;
     QLineEdit *hostLineEdit;
     QLineEdit *portLineEdit;
     QLabel *statusLabel;
     QPushButton *getFortuneButton;
     QPushButton *quitButton;
     QDialogButtonBox *buttonBox;

     QTcpSocket *tcpSocket;
     QTcpSocket tcpSocket2;
     QString currentFortune;
     QString mystring;
     quint16 blockSize;
    
};

#endif

To copy to clipboard, switch view to plain text mode

main.cpp

Qt Code:

Switch view

#include <QApplication>
#include "client.h"
 
 int main(int argc, char *argv[])
 {
     QApplication app(argc, argv);
     Client client;
     client.show();
     return client.exec();
 }

#include <QApplication>
#include "client.h"

 int main(int argc, char *argv[])
 {
     QApplication app(argc, argv);
     Client client;
     client.show();
     return client.exec();
 }

To copy to clipboard, switch view to plain text mode

**gQt** · 27th February 2008, 08:55

I forgot to say that the data I 'm trying to read with readLine looks like this:

$IIMWV,063,R,001.16,M,A*13
$IIMWV,042,R,002.66,M,A*14
$IIMWV,033,R,002.67,M,A*13
$IIMWV,041,R,001.71,M,A*12

with one new line available pr. second, so the problem can't be that readLine can't find a \n in the data. My problem is that the client connects, but readLine can't read anything.

Any help is deeply apreciated, thanks in advance!

Regards
gQt

**wysota** · 27th February 2008, 09:17

The fact that there is a connection between two hosts doesn't yet mean there is anything to read and even if there is, it might not be terminated with a newline character(s).

**gQt** · 27th February 2008, 12:13

Thanks for your reply!

I have tested that the data is available with the telnet command. The data comes with both LF and CR so canReadline /readLine should work. Output to terminal looks like this (changed all of the couts to english now)

function read_data()
after connectToHost
wait for connected loop
function read_data()
after connectToHost
wait for connected loop
function read_data()
after connectToHost
wait for connected loop
<Terminated with the Quit button>

<client.cpp>

Qt Code:

Switch view

#include <QtGui>
#include <QtNetwork>
#include "client.h"
#include <iostream.h>
#include <QtCore>    
#include <qdebug.h>
Client::Client(QWidget *parent)
        : QDialog(parent)
    {
        hostLabel = new QLabel(tr("&Server name:"));
        portLabel = new QLabel(tr("S&erver port:"));
	hostLineEdit = new QLineEdit("10.249.0.48");
        portLineEdit = new QLineEdit("4002");
        portLineEdit->setValidator(new QIntValidator(1, 65535, this));
 
        hostLabel->setBuddy(hostLineEdit);
        portLabel->setBuddy(portLineEdit);
	statusLabel = new QLabel(tr("This examples requires that you run the "
                                    "Fortune Server example as well."));
 
        getFortuneButton = new QPushButton(tr("Get Fortune"));
        getFortuneButton->setDefault(true);
        getFortuneButton->setEnabled(false);
 
        quitButton = new QPushButton(tr("Quit"));
 
        tcpSocket = new QTcpSocket(this);
 
        connect(hostLineEdit, SIGNAL(textChanged(const QString &)),
                this, SLOT(enableGetFortuneButton()));
        connect(portLineEdit, SIGNAL(textChanged(const QString &)),
                this, SLOT(enableGetFortuneButton()));
        connect(getFortuneButton, SIGNAL(clicked()),
                this, SLOT(read_data()));
        connect(quitButton, SIGNAL(clicked()), this, SLOT(close()));
       	connect(tcpSocket, SIGNAL(readyRead()), this, SLOT(read_data()));
	connect(tcpSocket, SIGNAL(error(QAbstractSocket::SocketError)), this, SLOT(displayError(QAbstractSocket::SocketError)));
 
        QHBoxLayout *buttonLayout = new QHBoxLayout;
        buttonLayout->addStretch(1);
        buttonLayout->addWidget(getFortuneButton);
        buttonLayout->addWidget(quitButton);
 
        QGridLayout *mainLayout = new QGridLayout;
        mainLayout->addWidget(hostLabel, 0, 0);
        mainLayout->addWidget(hostLineEdit, 0, 1);
        mainLayout->addWidget(portLabel, 1, 0);
        mainLayout->addWidget(portLineEdit, 1, 1);
       	mainLayout->addWidget(statusLabel, 2, 0, 1, 2);
        mainLayout->addLayout(buttonLayout, 3, 0, 1, 2);
        setLayout(mainLayout);
 
        setWindowTitle(tr("Fortune Client"));
        portLineEdit->setFocus();
    }
 
    void Client::read_data()
    {
	getFortuneButton->setEnabled(true);
	cout << "function read_data()\n";	
	tcpSocket->abort();
        tcpSocket->connectToHost(hostLineEdit->text(),
                                 portLineEdit->text().toInt());
 
	cout << ("after connectToHost\n");
 
 	if(tcpSocket->waitForConnected(-1))
	{
		cout <<"wait for connected loop\n";		
		if(tcpSocket->canReadLine())
		{
	      	 	mystring=tcpSocket->readLine();			
			qDebug() << "READ" << mystring;
			cout <<"canReadLine loop after readLine\n";	
		}	
		statusLabel->setText(mystring);
       		getFortuneButton->setEnabled(false);     
     	}
 
    }
    void Client::displayError(QAbstractSocket::SocketError socketError)
    {
        switch (socketError) {
        case QAbstractSocket::RemoteHostClosedError:
            break;
        case QAbstractSocket::HostNotFoundError:
            QMessageBox::information(this, tr("Fortune Client"),
                                     tr("The host was not found. Please check the "
                                        "host name and port settings."));
            break;
        case QAbstractSocket::ConnectionRefusedError:
            QMessageBox::information(this, tr("Fortune Client"),
                                     tr("The connection was refused by the peer. "
                                        "Make sure the fortune server is running, "
                                        "and check that the host name and port "
                                        "settings are correct."));
            break;
        default:
            QMessageBox::information(this, tr("Fortune Client"),
                                     tr("The following error occurred: %1.")
                                     .arg(tcpSocket->errorString()));
        }
 
        getFortuneButton->setEnabled(true);
    }
 
    void Client::enableGetFortuneButton()
    {
        getFortuneButton->setEnabled(!hostLineEdit->text().isEmpty()
                                     && !portLineEdit->text().isEmpty());
    }

#include <QtGui>
#include <QtNetwork>
#include "client.h"
#include <iostream.h>
#include <QtCore>    
#include <qdebug.h>
Client::Client(QWidget *parent)
        : QDialog(parent)
    {
        hostLabel = new QLabel(tr("&Server name:"));
        portLabel = new QLabel(tr("S&erver port:"));
	hostLineEdit = new QLineEdit("10.249.0.48");
        portLineEdit = new QLineEdit("4002");
        portLineEdit->setValidator(new QIntValidator(1, 65535, this));

        hostLabel->setBuddy(hostLineEdit);
        portLabel->setBuddy(portLineEdit);
	statusLabel = new QLabel(tr("This examples requires that you run the "
                                    "Fortune Server example as well."));

        getFortuneButton = new QPushButton(tr("Get Fortune"));
        getFortuneButton->setDefault(true);
        getFortuneButton->setEnabled(false);

        quitButton = new QPushButton(tr("Quit"));

        tcpSocket = new QTcpSocket(this);

        connect(hostLineEdit, SIGNAL(textChanged(const QString &)),
                this, SLOT(enableGetFortuneButton()));
        connect(portLineEdit, SIGNAL(textChanged(const QString &)),
                this, SLOT(enableGetFortuneButton()));
        connect(getFortuneButton, SIGNAL(clicked()),
                this, SLOT(read_data()));
        connect(quitButton, SIGNAL(clicked()), this, SLOT(close()));
       	connect(tcpSocket, SIGNAL(readyRead()), this, SLOT(read_data()));
	connect(tcpSocket, SIGNAL(error(QAbstractSocket::SocketError)), this, SLOT(displayError(QAbstractSocket::SocketError)));

        QHBoxLayout *buttonLayout = new QHBoxLayout;
        buttonLayout->addStretch(1);
        buttonLayout->addWidget(getFortuneButton);
        buttonLayout->addWidget(quitButton);
	
        QGridLayout *mainLayout = new QGridLayout;
        mainLayout->addWidget(hostLabel, 0, 0);
        mainLayout->addWidget(hostLineEdit, 0, 1);
        mainLayout->addWidget(portLabel, 1, 0);
        mainLayout->addWidget(portLineEdit, 1, 1);
       	mainLayout->addWidget(statusLabel, 2, 0, 1, 2);
        mainLayout->addLayout(buttonLayout, 3, 0, 1, 2);
        setLayout(mainLayout);

        setWindowTitle(tr("Fortune Client"));
        portLineEdit->setFocus();
    }

    void Client::read_data()
    {
	getFortuneButton->setEnabled(true);
	cout << "function read_data()\n";	
	tcpSocket->abort();
        tcpSocket->connectToHost(hostLineEdit->text(),
                                 portLineEdit->text().toInt());
	   	
	cout << ("after connectToHost\n");
	
 	if(tcpSocket->waitForConnected(-1))
	{
		cout <<"wait for connected loop\n";		
		if(tcpSocket->canReadLine())
		{
	      	 	mystring=tcpSocket->readLine();			
			qDebug() << "READ" << mystring;
			cout <<"canReadLine loop after readLine\n";	
		}	
		statusLabel->setText(mystring);
       		getFortuneButton->setEnabled(false);     
     	}

    }
    void Client::displayError(QAbstractSocket::SocketError socketError)
    {
        switch (socketError) {
        case QAbstractSocket::RemoteHostClosedError:
            break;
        case QAbstractSocket::HostNotFoundError:
            QMessageBox::information(this, tr("Fortune Client"),
                                     tr("The host was not found. Please check the "
                                        "host name and port settings."));
            break;
        case QAbstractSocket::ConnectionRefusedError:
            QMessageBox::information(this, tr("Fortune Client"),
                                     tr("The connection was refused by the peer. "
                                        "Make sure the fortune server is running, "
                                        "and check that the host name and port "
                                        "settings are correct."));
            break;
        default:
            QMessageBox::information(this, tr("Fortune Client"),
                                     tr("The following error occurred: %1.")
                                     .arg(tcpSocket->errorString()));
        }

        getFortuneButton->setEnabled(true);
    }

    void Client::enableGetFortuneButton()
    {
        getFortuneButton->setEnabled(!hostLineEdit->text().isEmpty()
                                     && !portLineEdit->text().isEmpty());
    }

To copy to clipboard, switch view to plain text mode

**wysota** · 27th February 2008, 12:18

Originally Posted by gQt

Thanks for your reply!

I have tested that the data is available with the telnet command. The data comes with both LF and CR so canReadline /readLine should work. Output to terminal looks like this (changed all of the couts to english now)

Does the output come to the terminal within a 1ns after establishing the connection? I doubt that... The data arrives, but it arrives later - you can't connect and expect the data to be already there.

**gQt** · 27th February 2008, 13:00

I'm doing an if (waitForConnected(-1)) after the connectToHost if that wat you mean?

Should I add anything else here?
(I'm new to Qt and Socket-programming)

From the read_data() function:

Qt Code:

Switch view

tcpSocket->abort();
        tcpSocket->connectToHost(hostLineEdit->text(),
                                 portLineEdit->text().toInt());
 
        cout << ("after connectToHost\n");
 
        if(tcpSocket->waitForConnected(-1))
        {
                cout <<"wait for connected loop\n";
                if(tcpSocket->canReadLine())
                {
                        mystring=tcpSocket->readLine();
                        qDebug() << "READ" << mystring;
                        cout <<"canReadLine loop after readLine\n";
                }
                statusLabel->setText(mystring);
                getFortuneButton->setEnabled(false);
        }

tcpSocket->abort();
        tcpSocket->connectToHost(hostLineEdit->text(),
                                 portLineEdit->text().toInt());

        cout << ("after connectToHost\n");

        if(tcpSocket->waitForConnected(-1))
        {
                cout <<"wait for connected loop\n";
                if(tcpSocket->canReadLine())
                {
                        mystring=tcpSocket->readLine();
                        qDebug() << "READ" << mystring;
                        cout <<"canReadLine loop after readLine\n";
                }
                statusLabel->setText(mystring);
                getFortuneButton->setEnabled(false);
        }

To copy to clipboard, switch view to plain text mode

**wysota** · 27th February 2008, 13:37

Originally Posted by gQt

I'm doing an if (waitForConnected(-1)) after the connectToHost if that wat you mean?

No, this waits for the connection to be established, not for the data to be ready.

Should I add anything else here?

QAbstractSocket::waitForReadyRead

(I'm new to Qt and Socket-programming)

That should motivate you to do some more reading.

**gQt** · 27th February 2008, 14:23

Thanks a mill wysota

!
I hadn't thought about the waitForReadyRead- that I had to wait for the data to be ready to read also.

**wysota** · 27th February 2008, 14:30

Be aware that the fact that waitForReadyRead returns means there is something to read, not that everything is ready to be read.

**gQt** · 29th February 2008, 08:09

sorry for postin the start of the thread again,

I have added a while waitForReadyRead loop inside the if waitForConnected and now it works.

Qt Code:

Switch view

void Client::read_data()
    {
	getFortuneButton->setEnabled(true);
	//cout << "function read_data()\n";	
	tcpSocket->abort();
        tcpSocket->connectToHost(hostLineEdit->text(),
                                 portLineEdit->text().toInt());
 
	//cout << ("after connectToHost\n");
 
	if(tcpSocket->waitForConnected(-1))
	{
		//cout <<"wait for connected loop\n";		
 
		while(tcpSocket->waitForReadyRead(-1)) 
		{
			while(tcpSocket->canReadLine())
			{
	      	 		mystring=tcpSocket->readLine();			
				qDebug() << mystring;					
				statusLabel->setText(mystring);
			}	
			getFortuneButton->setEnabled(false);  
		}
 
 
     	}   
 
    }

void Client::read_data()
    {
	getFortuneButton->setEnabled(true);
	//cout << "function read_data()\n";	
	tcpSocket->abort();
        tcpSocket->connectToHost(hostLineEdit->text(),
                                 portLineEdit->text().toInt());
	   	
	//cout << ("after connectToHost\n");
	
	if(tcpSocket->waitForConnected(-1))
	{
		//cout <<"wait for connected loop\n";		
		
		while(tcpSocket->waitForReadyRead(-1)) 
		{
			while(tcpSocket->canReadLine())
			{
	      	 		mystring=tcpSocket->readLine();			
				qDebug() << mystring;					
				statusLabel->setText(mystring);
			}	
			getFortuneButton->setEnabled(false);  
		}
		
       		
     	}   
	
    }

To copy to clipboard, switch view to plain text mode

**wysota** · 29th February 2008, 09:35

I still don't see you use waitForReadyRead...

Qt Code:

Switch view

x->connectToHost(...);
x->waitForConnected(...);
while(x->waitForReadyRead(10000)){
  x->readAll(); // or canReadLine && readLine...
}

x->connectToHost(...);
x->waitForConnected(...);
while(x->waitForReadyRead(10000)){
  x->readAll(); // or canReadLine && readLine...
}

To copy to clipboard, switch view to plain text mode

Thread: readLine problem

Thread Tools

Search Thread

Display

readLine problem

Re: readLine problem

Re: readLine problem

Re: readLine problem

Re: readLine problem

Re: readLine problem

Re: readLine problem

Re: readLine problem

Re: readLine problem

The following user says thank you to wysota for this useful post:

Re: readLine problem

Re: readLine problem

Similar Threads

problem with opengl, zooming, drawpixels, and origin

Tricky problem with ARGB widget / UpdateLayeredWindow

QTextStream, input and readLine()

problem with reading input data in qt

Architecture problem using threads, custom events and signals/slots

Bookmarks

Bookmarks

Posting Permissions