多进程回声服务器实现（一）

#include #include #include #include #include #include #include #define PORT "10000"#define BUFFER_SIZE 1024#define TRUE 1#define FALSE 0// 错误处理void error_handler(const char *message) { fputs(message, stderr); fputc('n', stderr); exit(1);}// 子进程处理void child_handler(int sig) { if (sig == SIGCHLD) { int state; pid_t pid = waitpid(-1, &state, WNOHANG); if (WIFEXITED(state)) { printf("Child %d process end, return %dn", pid, WEXITSTATUS(state)); } }}int main() { int server_sock; server_sock = socket(PF_INET, SOCK_STREAM, 0); if (server_sock == -1) { error_handler("socket() error"); } // 消除Timewait时间不可分配地址 int option = TRUE; int op_len = sizeof(option); setsockopt(server_sock, SOL_SOCKET, SO_REUSEADDR, (void *)&option, op_len); // 发送缓存设置 int send_buffer = BUFFER_SIZE; op_len = sizeof(send_buffer); setsockopt(server_sock, SOL_SOCKET, SO_SNDBUF, (void *)&send_buffer, op_len); // 接收缓存设置 int receive_buffer = BUFFER_SIZE; op_len = sizeof(receive_buffer); setsockopt(server_sock, SOL_SOCKET, SO_RCVBUF, (void *)&receive_buffer, op_len); // 子进程处理 struct sigaction act; act.sa_flags = 0; sigemptyset(&act.sa_mask); act.sa_handler = child_handler; sigaction(SIGCHLD, &act, 0); // 地址初始化 struct sockaddr_in server_address; memset(&server_address, 0, sizeof(server_address)); server_address.sin_family = AF_INET; server_address.sin_addr.s_addr = htonl(INADDR_ANY); server_address.sin_port = htons(atoi(PORT)); if (bind(server_sock, (struct sockaddr *)&server_address, sizeof(server_address)) == -1) { error_handler("bind() error"); } if (listen(server_sock, 1024) == -1) { error_handler("listen() error"); } int client_sock; struct sockaddr_in client_address; socklen_t client_address_len = sizeof(client_address); while (1) { client_sock = accept(server_sock, (struct sockaddr *)&client_address, &client_address_len); if (client_sock == -1) { continue; } else { puts("new connect..."); } pid_t pid = fork(); if (pid == 0) { // 子进程逻辑 close(server_sock); char buffer[BUFFER_SIZE]; FILE *write_fp = fdopen(client_sock, "w"); FILE *read_fp = fdopen(dup(client_sock), "r"); while (1) { if (fgets(buffer, BUFFER_SIZE - 1, read_fp) == NULL) { break; } fputs(buffer, write_fp); fflush(write_fp); } char str[] = "Thank you!"; fputs(str, write_fp); fflush(write_fp); fclose(write_fp); fclose(read_fp); return 0; } else { // 父进程逻辑 close(client_sock); continue; } } return 0;}

客户端：

#include #include #include #include #include #include #define IP "127.0.0.1"#define PORT "10000"#define BUFFER_SIZE 1024void error_handler(const char *message) { fputs(message, stderr); fputc('n', stderr); exit(1);}int main() { int sock; sock = socket(PF_INET, SOCK_STREAM, 0); if (sock == -1) { error_handler("socket() error"); } struct sockaddr_in address; memset(&address, 0, sizeof(address)); address.sin_family = AF_INET; address.sin_addr.s_addr = inet_addr(IP); address.sin_port = htons(atoi(PORT)); if (connect(sock, (struct sockaddr *)&address, sizeof(address)) == -1) { error_handler("connect() error"); } char message[BUFFER_SIZE]; FILE *read_fp = fdopen(sock, "r"); FILE *write_fp = fdopen(dup(sock), "w"); while (1) { fputs("Input Message: ", stdout); fgets(message, BUFFER_SIZE, stdin); if (!strcmp(message, "Qn") || !strcmp(message, "qn")) { shutdown(fileno(write_fp), SHUT_WR); fclose(write_fp); break; } fputs(message, write_fp); fflush(write_fp); fgets(message, BUFFER_SIZE, read_fp); printf("Message from server: %sn", message); } fgets(message, BUFFER_SIZE, read_fp); printf("last Message from server: %sn", message); fclose(read_fp); return 0;}