socket通信通信过程

Posted 2022-03-19 thefist11

1.
1. 1 server.cpp

// Server side C program to demonstrate Socket programming
#include <stdio.h>
#include <sys/socket.h>
#include <unistd.h>
#include <stdlib.h>
#include <netinet/in.h>
#include <string.h>

#define PORT 8080
int main(int argc, char const *argv[])

    int server_fd, new_socket; long valread;
    struct sockaddr_in address;
    int addrlen = sizeof(address);
    
    char *hello = "Hello from server";
    
    // Creating socket file descriptor
    if ((server_fd = socket(AF_INET, SOCK_STREAM, 0)) == 0)
    
        perror("In socket");
        exit(EXIT_FAILURE);
    
    

    address.sin_family = AF_INET;
    address.sin_addr.s_addr = INADDR_ANY;
    address.sin_port = htons( PORT );
    
    memset(address.sin_zero, '\\0', sizeof address.sin_zero);
    
    
    if (bind(server_fd, (struct sockaddr *)&address, sizeof(address))<0)
    
        perror("In bind");
        exit(EXIT_FAILURE);
    
    if (listen(server_fd, 10) < 0)
    
        perror("In listen");
        exit(EXIT_FAILURE);
    
    while(1)
    
        printf("\\n+++++++ Waiting for new connection ++++++++\\n\\n");
        if ((new_socket = accept(server_fd, (struct sockaddr *)&address, (socklen_t*)&addrlen))<0)
        
            perror("In accept");
            exit(EXIT_FAILURE);
        
        
        char buffer[30000] = 0;
        valread = read( new_socket , buffer, 30000);
        printf("%s\\n",buffer );
        write(new_socket , hello , strlen(hello));
        printf("------------------Hello message sent-------------------\\n");
        close(new_socket);
    
    return 0;

1.2 client.cpp

// Client side C/C++ program to demonstrate Socket programming
#include <stdio.h>
#include <sys/socket.h>
#include <stdlib.h>
#include <unistd.h>
#include <netinet/in.h>
#include <string.h>
#include <arpa/inet.h>

#define PORT 8080

int main(int argc, char const *argv[])

 

    int sock = 0; long valread;
    struct sockaddr_in serv_addr;
    char *hello = "Hello from client";
    char buffer[1024] = 0;
    if ((sock = socket(AF_INET, SOCK_STREAM, 0)) < 0)
    
        printf("\\n Socket creation error \\n");
        return -1;
    
    
    memset(&serv_addr, '0', sizeof(serv_addr));
    
    serv_addr.sin_family = AF_INET;
    serv_addr.sin_port = htons(PORT);
    
    const char chhost[256]="127.0.0.1";
    if (argc > 1)
       strcpy(chhost, argv[1]);
	
    printf("\\n %s \\n", chhost);
    // Convert IPv4 and IPv6 addresses from text to binary form
    if(inet_pton(AF_INET, chhost, &serv_addr.sin_addr)<=0)
    
        printf("\\nInvalid address/ Address not supported \\n");
        return -1;
    
    
    if (connect(sock, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) < 0)
    
        printf("\\nConnection Failed \\n");
        return -1;
    
    send(sock , hello , strlen(hello) , 0);
    printf("Hello message sent\\n");
    valread = read( sock , buffer, 1024);
    printf("%s\\n",buffer );
    return 0;