client.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#define IPADDRESS "127.0.0.1"
#define SERV_PORT 8080
#define MAXSIZE 1024

int main(int argc, char *argv[]) {
    int sockfd;
    struct sockaddr_in servaddr;

    // socket: create socket
    sockfd = socket(AF_INET, SOCK_STREAM, 0);
    memset(&servaddr, 0, sizeof(servaddr));

    servaddr.sin_family = AF_INET;
    servaddr.sin_port = htons(SERV_PORT);
    inet_pton(AF_INET, IPADDRESS, &servaddr.sin_addr);
    // connect: initiate a connection on a socket
    connect(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr));

    while (1) {
        char buf[MAXSIZE] = {0};
        scanf("%s", buf);
        printf("sent msg:%s\n", buf);
        send(sockfd, buf, strlen(buf), 0);

        memset(buf, 0, sizeof(buf));
        recv(sockfd, buf, MAXSIZE, 0);

        printf("read msg:%s\n", buf);
        if (strcmp(buf, "bye") == 0) {
            printf("close client!\n");
            close(sockfd);
            break;
        }
    }
    return 0;
}