修正版

client.c

@@ -0,0 +1,65 @@
+#include <arpa/inet.h>
+#include <netdb.h>
+#include <netinet/in.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <unistd.h>
+
+#define BUFFER_SIZE 1024
+
+int main(int argc, char *argv[]) {
+    int client_socket = -1;
+    struct addrinfo hints, *res = NULL;
+    char *address = NULL;
+    char *port = NULL;
+    if (argc < 3) {
+        fprintf(stderr, "Usage: %s <server_address> <server_port>\n", argv[0]);
+        exit(1);
+    }
+    address = argv[1];
+    port = argv[2];
+    memset(&hints, 0, sizeof(hints));
+    hints.ai_family = AF_UNSPEC;      
+    hints.ai_socktype = SOCK_STREAM;  
+    int status = getaddrinfo(address, port, &hints, &res);
+    if (status != 0) {
+        fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(status));
+        exit(1);
+    }
+    struct addrinfo *p;
+    for (p = res; p != NULL; p = p->ai_next) {
+        client_socket = socket(p->ai_family, p->ai_socktype, p->ai_protocol);
+        if (client_socket < 0) {
+            perror("Socket Error");
+            continue;
+        }
+        if (connect(client_socket, p->ai_addr, p->ai_addrlen) < 0) {
+            perror("Connect Error");
+            close(client_socket);
+            continue;
+        }
+        break; 
+    }
+    if (p == NULL) {
+        fprintf(stderr, "Failed to connect to %s:%s\n", address, port);
+        freeaddrinfo(res);
+        exit(1);
+    }
+    freeaddrinfo(res);
+    printf("Connected to %s:%s\n", address, port);
+    char send_buffer[BUFFER_SIZE];
+    char recv_buffer[BUFFER_SIZE];
+    ssize_t bytes_sent, bytes_received;
+    while (fgets(send_buffer, sizeof(send_buffer), stdin) != NULL) {
+        size_t len = strlen(send_buffer);
+        bytes_sent = send(client_socket, send_buffer, len, 0);
+        if (bytes_sent < 0) {
+            perror("Send Error");
+            break;
+        }
+    }
+    printf("Closing connection.\n");
+    close(client_socket);
+}

server.c

@@ -0,0 +1,121 @@
+#include <arpa/inet.h>
+#include <netdb.h>
+#include <netinet/in.h>
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <unistd.h>
+
+#define BUFFER_SIZE 1024
+
+void *handle_client(void *arg);
+
+int main(int argc, char *argv[]) {
+    int server_socket = -1;
+    struct addrinfo hints, *res = NULL;
+    int socket_option = 1;
+    char *address = NULL;
+    char *port = NULL;
+    if (argc >= 2) {
+        address = argv[1];
+    } else {
+        address = "0.0.0.0";
+    }
+    if (argc >= 3) {
+        port = argv[2];
+    } else {
+        port = "8080";
+    }
+    memset(&hints, 0, sizeof(hints));
+    hints.ai_family = AF_UNSPEC;     
+    hints.ai_socktype = SOCK_STREAM; 
+    hints.ai_flags = AI_PASSIVE;     
+    int status = getaddrinfo(address, port, &hints, &res);
+    if (status != 0) {
+        fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(status));
+        goto cleanup;
+    }
+    struct addrinfo *p;
+    for (p = res; p != NULL; p = p->ai_next) {
+        server_socket = socket(p->ai_family, p->ai_socktype, p->ai_protocol);
+        if (server_socket < 0) {
+            perror("Socket Error");
+            continue;
+        }
+        if (setsockopt(server_socket, SOL_SOCKET, SO_REUSEADDR, &socket_option, sizeof(socket_option)) < 0) {
+            perror("Can't set socket option");
+            close(server_socket);
+            continue;
+        }
+        if (bind(server_socket, p->ai_addr, p->ai_addrlen) < 0) {
+            perror("Can't bind");
+            close(server_socket);
+            continue;
+        }
+        break;
+    }
+    if (p == NULL) {
+        fprintf(stderr, "Failed to bind to any address\n");
+        goto cleanup;
+    }
+    freeaddrinfo(res);
+    if (listen(server_socket, SOMAXCONN) < 0) {
+        perror("Can't listen");
+        goto cleanup;
+    }
+    printf("Server is listening on %s:%s\n", address, port);
+    while (1) {
+        struct sockaddr_storage client_address;
+        socklen_t client_address_len = sizeof(client_address);
+        int new_socket = accept(server_socket, (struct sockaddr *)&client_address, &client_address_len);
+        if (new_socket < 0) {
+            perror("Accept Error");
+            continue;
+        }
+        pthread_t thread_id;
+        int *pclient = malloc(sizeof(int));
+        if (pclient == NULL) {
+            perror("Malloc Error");
+            close(new_socket);
+            continue;
+        }
+        *pclient = new_socket;
+        if (pthread_create(&thread_id, NULL, handle_client, pclient) != 0) {
+            perror("Thread Creation Error");
+            close(new_socket);
+            free(pclient);
+            continue;
+        } else {
+            pthread_detach(thread_id);
+        }
+    }
+
+cleanup:
+    if (res != NULL) {
+        freeaddrinfo(res);
+    }
+    if (server_socket != -1) {
+        close(server_socket);
+    }
+    exit(1);
+}
+
+void *handle_client(void *arg) {
+    int client_socket = *((int *)arg);
+    free(arg);
+    char buffer[BUFFER_SIZE];
+    ssize_t bytes_read;
+    while ((bytes_read = read(client_socket, buffer, sizeof(buffer))) > 0) {
+        if (write(STDOUT_FILENO, buffer, bytes_read) < 0) {
+            perror("Write Error");
+            break;
+        }
+    }
+    if (bytes_read < 0) {
+        perror("Read Error");
+    }
+    close(client_socket);
+    return NULL;
+}