linux dbus 客户端和服务器示例代码

// 建立与系统总线的连接conn = dbus_bus_get(DBUS_BUS_SYSTEM, &err);if (dbus_error_is_set(&err)) {    fprintf(stderr, "Connection Error (%s)\n", err.message);    dbus_error_free(&err);}if (!conn) {    exit(1);}
// 注册服务名为"org.example.TestServer"int ret = dbus_bus_request_name(conn, "org.example.TestServer",        DBUS_NAME_FLAG_REPLACE_EXISTING, &err);if (dbus_error_is_set(&err)) {    fprintf(stderr, "Name Error (%s)\n", err.message);    dbus_error_free(&err);}if (DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER != ret) {    exit(1);}
printf("Listening for requests...\n");
// 循环等待消息while (true) {    DBusMessage *msg;
    // 读取消息并进行处理    dbus_connection_read_write(conn, 0);    msg = dbus_connection_pop_message(conn);    if (msg == NULL) {        continue;    }
    // 判断消息类型，不同类型的消息需要做不同的处理    if (dbus_message_is_method_call(msg, "org.example.TestServer",                "HelloWorld")) {        DBusMessage *reply;
        // 构造回复消息        reply = dbus_message_new_method_return(msg);        if (reply == NULL) {            continue;        }
        // 添加回复消息的内容        dbus_message_append_args(reply, DBUS_TYPE_STRING, "Hello World!", DBUS_TYPE_INVALID);
        // 发送回复消息        if (!dbus_connection_send(conn, reply, NULL)) {            fprintf(stderr, "Out of memory\n");            exit(1);        }        dbus_connection_flush(conn);        dbus_message_unref(reply);    }
    dbus_message_unref(msg);} 
return 0;

// 建立与系统总线的连接conn = dbus_bus_get(DBUS_BUS_SYSTEM, &err);if (dbus_error_is_set(&err)) {    fprintf(stderr, "Connection Error (%s)\n", err.message);    dbus_error_free(&err);}if (!conn) {    exit(1);}
// 构造调用"org.example.TestServer"的"HellowWorld"方法的消息DBusMessage *msg;msg = dbus_message_new_method_call("org.example.TestServer",        "/org/example/TestObject", "org.example.TestInterface", "HelloWorld");if (msg == NULL) {    fprintf(stderr, "Message Null\n");    exit(1);}
// 发送消息并等待回复DBusMessage *reply;reply = dbus_connection_send_with_reply_and_block(conn, msg,        -1, &err);if (dbus_error_is_set(&err)) {    fprintf(stderr, "Reply Error (%s)\n", err.message);    dbus_error_free(&err);}if (reply == NULL) {    fprintf(stderr, "Reply Null\n");    exit(1);}
// 读取回复消息的内容char *result;dbus_message_get_args(reply, &err,        DBUS_TYPE_STRING, &result, DBUS_TYPE_INVALID);if (dbus_error_is_set(&err)) {    fprintf(stderr, "Arg Error (%s)\n", err.message);    dbus_error_free(&err);}
printf("Received Reply: %s\n", result);
dbus_message_unref(msg);dbus_message_unref(reply);dbus_connection_close(conn);
return 0;