用C语言编写Socket客户端与服务端，使用TCP或者UDP通信，请给出完整代码

以下是使用TCP协议的Socket客户端与服务端的完整代码示例：

### 服务端代码（server.c）

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

#define BUF_SIZE 1024

int main(int argc, char *argv[]) {
    int serv_sock, clnt_sock;
    char message[BUF_SIZE];
    int str_len, i;

    struct sockaddr_in serv_addr, clnt_addr;
    socklen_t clnt_addr_size;

    if (argc != 2) {
        printf("Usage: %s <port>\n", argv[0]);
        exit(1);
    }

    serv_sock = socket(PF_INET, SOCK_STREAM, 0);
    if (serv_sock == -1) {
        perror("socket");
        exit(1);
    }

    memset(&serv_addr, 0, sizeof(serv_addr));
    serv_addr.sin_family = AF_INET;
    serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    serv_addr.sin_port = htons(atoi(argv[1]));

    if (bind(serv_sock, (struct sockaddr*)&serv_addr, sizeof(serv_addr)) == -1) {
        perror("bind");
        exit(1);
    }

    if (listen(serv_sock, 5) == -1) {
        perror("listen");
        exit(1);
    }

    clnt_addr_size = sizeof(clnt_addr);

    for (i = 0; i < 5; i++) {
        clnt_sock = accept(serv_sock, (struct sockaddr*)&clnt_addr, &clnt_addr_size);
        if (clnt_sock == -1) {
            perror("accept");
            exit(1);
        }

        while ((str_len = read(clnt_sock, message, BUF_SIZE)) != 0) {
            write(clnt_sock, message, str_len);
        }

        close(clnt_sock);
    }

    close(serv_sock);

    return 0;
}

### 客户端代码（client.c）

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

#define BUF_SIZE 1024

int main(int argc, char *argv[]) {
    int sock;
    char message[BUF_SIZE];
    int str_len;
    struct sockaddr_in serv_addr;

    if (argc != 3) {
        printf("Usage: %s <IP> <port>\n", argv[0]);
        exit(1);
    }

    sock = socket(PF_INET, SOCK_STREAM, 0);
    if (sock == -1) {
        perror("socket");
        exit(1);
    }

    memset(&serv_addr, 0, sizeof(serv_addr));
    serv_addr.sin_family = AF_INET;
    serv_addr.sin_addr.s_addr = inet_addr(argv[1]);
    serv_addr.sin_port = htons(atoi(argv[2]));

    if (connect(sock, (struct sockaddr*)&serv_addr, sizeof(serv_addr)) == -1) {
        perror("connect");
        exit(1);
    }

    while (1) {
        fputs("Input message(Q to quit): ", stdout);
        fgets(message, BUF_SIZE, stdin);

        if (!strcmp(message, "q\n") || !strcmp(message, "Q\n")) {
            break;
        }

        write(sock, message, strlen(message));
        str_len = read(sock, message, BUF_SIZE - 1);
        message[str_len] = '\0';
        printf("Message from server: %s", message);
    }

    close(sock);

    return 0;
}

使用UDP协议的Socket客户端与服务端的完整代码示例：

### 服务端代码（udp_server.c）

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

#define BUF_SIZE 1024

int main(int argc, char *argv[]) {
    int serv_sock;
    char message[BUF_SIZE];
    int str_len, i;

    struct sockaddr_in serv_addr, clnt_addr;
    socklen_t clnt_addr_size;

    if (argc != 2) {
        printf("Usage: %s <port>\n", argv[0]);
        exit(1);
    }

    serv_sock = socket(PF_INET, SOCK_DGRAM, 0);
    if (serv_sock == -1) {
        perror("socket");
        exit(1);
    }

    memset(&serv_addr, 0, sizeof(serv_addr));
    serv_addr.sin_family = AF_INET;
    serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    serv_addr.sin_port = htons(atoi(argv[1]));

    if (bind(serv_sock, (struct sockaddr*)&serv_addr, sizeof(serv_addr)) == -1) {
        perror("bind");
        exit(1);
    }

    for (i = 0; i < 5; i++) {
        clnt_addr_size = sizeof(clnt_addr);
        str_len = recvfrom(serv_sock, message, BUF_SIZE, 0, (struct sockaddr*)&clnt_addr, &clnt_addr_size);
        sendto(serv_sock, message, str_len, 0, (struct sockaddr*)&clnt_addr, clnt_addr_size);
    }

    close(serv_sock);

    return 0;
}

### 客户端代码（udp_client.c）

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

#define BUF_SIZE 1024

int main(int argc, char *argv[]) {
    int sock;
    char message[BUF_SIZE];
    int str_len;
    struct sockaddr_in serv_addr;

    if (argc != 3) {
        printf("Usage: %s <IP> <port>\n", argv[0]);
        exit(1);
    }

    sock = socket(PF_INET, SOCK_DGRAM, 0);
    if (sock == -1) {
        perror("socket");
        exit(1);
    }

    memset(&serv_addr, 0, sizeof(serv_addr));
    serv_addr.sin_family = AF_INET;
    serv_addr.sin_addr.s_addr = inet_addr(argv[1]);
    serv_addr.sin_port = htons(atoi(argv[2]));

    while (1) {
        fputs("Input message(Q to quit): ", stdout);
        fgets(message, BUF_SIZE, stdin);

        if (!strcmp(message, "q\n") || !strcmp(message, "Q\n")) {
            break;
        }

        sendto(sock, message, strlen(message), 0, (struct sockaddr*)&serv_addr, sizeof(serv_addr));
        str_len = recvfrom(sock, message, BUF_SIZE - 1, 0, NULL, NULL);
        message[str_len] = '\0';
        printf("Message from server: %s", message);
    }

    close(sock);

    return 0;
}

以上代码仅供参考，实际使用时需要根据具体需求进行修改。