用c语言，建立一个UDP,TCP的client和serve的socket,并进行通信

UDP：

Client端：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>

#define PORT 8888
#define MAXLINE 1024

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

    if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
        perror("socket error");
        exit(1);
    }

    bzero(&servaddr, sizeof(servaddr));
    servaddr.sin_family = AF_INET;
    servaddr.sin_port = htons(PORT);
    if (inet_pton(AF_INET, argv[1], &servaddr.sin_addr) <= 0) {
        printf("inet_pton error for %s\n", argv[1]);
        exit(1);
    }

    while (fgets(sendline, MAXLINE, stdin) != NULL) {
        sendto(sockfd, sendline, strlen(sendline), 0, (struct sockaddr *)&servaddr, sizeof(servaddr));
        int n = recvfrom(sockfd, recvline, MAXLINE, 0, NULL, NULL);
        recvline[n] = 0;
        printf("recvline: %s", recvline);
    }

    close(sockfd);
    exit(0);
}

Server端：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>

#define PORT 8888
#define MAXLINE 1024

int main(int argc, char *argv[]) {
    int sockfd;
    struct sockaddr_in servaddr, cliaddr;
    char buf[MAXLINE];
    socklen_t len;
    int n;

    if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
        perror("socket error");
        exit(1);
    }

    bzero(&servaddr, sizeof(servaddr));
    servaddr.sin_family = AF_INET;
    servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
    servaddr.sin_port = htons(PORT);

    if (bind(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr)) < 0) {
        perror("bind error");
        exit(1);
    }

    while (1) {
        len = sizeof(cliaddr);
        n = recvfrom(sockfd, buf, MAXLINE, 0, (struct sockaddr *)&cliaddr, &len);
        sendto(sockfd, buf, n, 0, (struct sockaddr *)&cliaddr, len);
        buf[n] = 0;
        printf("recvline: %s", buf);
    }

    close(sockfd);
    exit(0);
}

TCP：

Client端：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>

#define PORT 8888
#define MAXLINE 1024

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

    if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
        perror("socket error");
        exit(1);
    }

    bzero(&servaddr, sizeof(servaddr));
    servaddr.sin_family = AF_INET;
    servaddr.sin_port = htons(PORT);
    if (inet_pton(AF_INET, argv[1], &servaddr.sin_addr) <= 0) {
        printf("inet_pton error for %s\n", argv[1]);
        exit(1);
    }

    if (connect(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr)) < 0) {
        perror("connect error");
        exit(1);
    }

    while (fgets(sendline, MAXLINE, stdin) != NULL) {
        write(sockfd, sendline, strlen(sendline));
        int n = read(sockfd, recvline, MAXLINE);
        recvline[n] = 0;
        printf("recvline: %s", recvline);
    }

    close(sockfd);
    exit(0);
}

Server端：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>

#define PORT 8888
#define MAXLINE 1024

int main(int argc, char *argv[]) {
    int listenfd, connfd;
    struct sockaddr_in servaddr, cliaddr;
    char buf[MAXLINE];
    socklen_t len;
    int n;

    if ((listenfd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
        perror("socket error");
        exit(1);
    }

    bzero(&servaddr, sizeof(servaddr));
    servaddr.sin_family = AF_INET;
    servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
    servaddr.sin_port = htons(PORT);

    if (bind(listenfd, (struct sockaddr *)&servaddr, sizeof(servaddr)) < 0) {
        perror("bind error");
        exit(1);
    }

    if (listen(listenfd, 10) < 0) {
        perror("listen error");
        exit(1);
    }

    while (1) {
        len = sizeof(cliaddr);
        connfd = accept(listenfd, (struct sockaddr *)&cliaddr, &len);
        while ((n = read(connfd, buf, MAXLINE)) > 0) {
            write(connfd, buf, n);
            buf[n] = 0;
            printf("recvline: %s", buf);
        }
        close(connfd);
    }

    close(listenfd);
    exit(0);
}