QT前台与后台程序通过socket通信

#include "dialog.h"
#include "ui_dialog.h"

Dialog::Dialog(QWidget *parent)
    : QDialog(parent), ui(new Ui::Dialog)
{
    ui->setupUi(this);
    tcpSocket = new QTcpSocket( this );
    ui->lineEdit->setText("192.168.244.66");
    ui->lineEdit_2->setText( "2010" );

    connect( tcpSocket, SIGNAL(error(int)), this, SLOT(errMsg(int)) );
    connect( ui->pushButton, SIGNAL(clicked()), this, SLOT(on_pushButton_clicked(bool)) );
    connect( tcpSocket, SIGNAL(readyRead()), this, SLOT(recvMsg()) );
}

Dialog::~Dialog()
{
    delete ui;
}

void Dialog::on_pushButton_clicked(bool checked)
{
        QString port;
        int port_Int;

        port = ui->lineEdit_2->text();
        port_Int = port.toInt();

        tcpSocket->connectToHost(QHostAddress(ui->lineEdit->text()), port_Int);

         //waitForConnected的参数是超时时间

        if (!tcpSocket->waitForConnected(2)) {
            tcpSocket->disconnectFromHost();
            return;
        }
        QTextStream out(tcpSocket);
        out << ui->lineEdit_3->text()<< endl;
}

void Dialog::recvMsg()
{

    QString res;

    res += tcpSocket->readAll();
    ui->textEdit->setText(res);
    ui->textEdit->moveCursor(QTextCursor::End);

    tcpSocket->disconnectFromHost();
}

void Dialog::errMsg( int errNo )
{
   qWarning( "this is err!!!!" );
}

#include 
#include 
#include 
#include 
#include 

#define RCV_BUF_LEN 200

int main( int ac, char **av )
{
        int sock;
        int client_Sock;
        int ret;
        char inputBuf[200];
        char recvBuf[RCV_BUF_LEN];
        struct sockaddr_in svrAddr;
        int i;
        int val;

        /** 创建监听套接字 **/
        if ( (sock = socket(AF_INET, SOCK_STREAM, 0)) < 0 ){
                printf("socket error!/n");
                return -1;
        }

        /** 指定监听端口和地址 **/
        memset( &svrAddr, 0x00, sizeof(svrAddr) );
        svrAddr.sin_family =AF_INET;
        svrAddr.sin_addr.s_addr = htonl( INADDR_ANY );
        svrAddr.sin_port = htons( 2010 );

        setsockopt(sock,SOL_SOCKET,SO_REUSEADDR, (char *)&val, sizeof(val) );

        /** 绑定监听套接字和端口 **/
        if ( bind(sock, (struct sockaddr *)&svrAddr, sizeof(svrAddr)) != 0 ){
                printf("bind error!/n");
                return -1;
        }

        /** 监听套接字 */
        if ( listen( sock, 10 ) != 0 ){
                printf("listen error!/n");
                return -1;
        }

        while( 1 ){
                /** 等待连接请求 **/
                printf("等待客户端连接请求../n");
                if ( (client_Sock = accept( sock, NULL, 0 )) < 0 ){
                        printf("accept error!/n");
                        return -1;
                }

                printf("客户端已连入../n");

                while( 1 ){
                        memset( recvBuf, 0x00, RCV_BUF_LEN );
                        ret = recv( client_Sock, recvBuf, RCV_BUF_LEN, 0 );
                        recvBuf[strlen(recvBuf) - 1] = 0;
                        if ( ret > 0 ){
                                printf("接收到: [%s]/n", recvBuf);
                                for( i = 0; i < strlen(recvBuf); i++ ){
                                        if ( recvBuf[i] > 96 && recvBuf[i] < 123 ){
                                                recvBuf[i] -= 32;
                                        }
                                }

                                ret = send( client_Sock, recvBuf, strlen(recvBuf), 0 );
                                if ( ret > 0 ){
                                        printf("处理并返回成功../n");
                                }
                                else if ( ret < 0 ){
                                        printf("返回客户端错误../n");
                                }
                        }
                        else if ( ret == 0 ){
                                printf("客户端断开../n");
                                break;
                        }
                        else{
                                printf("rcv error!/n");
                                break;
                        }
                }

        }

        return 0;
}