相关疑难解决方法(0)

当多个进程访问单个SQLite数据库文件时,如何确保正确性？

使用ios4.x我可以使用下面的代码获取"kCTMessageReceivedNotification"通知时的消息

CTTelephonyCenterAddObserver( ct, NULL, callback,NULL,NULL, CFNotificationSuspensionBehaviorHold); 

if ([notifyname isEqualToString:@"kCTMessageReceivedNotification"])//receive message
    {

        NSDictionary *info = (NSDictionary *)userInfo;
        CFNumberRef msgID = (CFNumberRef)[info objectForKey:@"kCTMessageIdKey"];
        int result;
        CFNumberGetValue((CFNumberRef)msgID, kCFNumberSInt32Type, &result);   
        Class CTMessageCenter = NSClassFromString(@"CTMessageCenter");
        id mc = [CTMessageCenter sharedMessageCenter];
        id incMsg = [mc incomingMessageWithId: result];}

但是对于ios5我不能这样做因为incMsg是零,所以我该怎么做才能得到消息？

谢谢

页面http://www.sqlite.org/threadsafe.html提到:

• 单线程
• 多线程
• 序列化

哪种模式是在iOS 5中集成的sqlite编译的？

随着iOS 5的发布,我们在为sqlite数据库设置序列化选项时会遇到越来越多的错误(因此将其保存用于多线程).我们在sqlite3_config上收到SQLITE_MISUSE错误代码.有人注意到这种奇怪的行为吗？有人知道如何解决这个问题吗？它在之前的iOS版本上运行得非常好.

这是代码:

- (sqlite3 *)getNewDBConnection {
    NSLog(@"sqlite3 lib version: %s", sqlite3_libversion());

    //sqlite3_config() has to be called before any sqlite3_open calls.

    if (sqlite3_threadsafe() > 0) {
        int retCode = sqlite3_config(SQLITE_CONFIG_SERIALIZED);
        if (retCode == SQLITE_OK) {
            NSLog(@"Can now use sqlite on multiple threads, using the same connection");
        } else {
            NSLog(@"setting sqlite thread safe mode to serialized failed!!! return code: %d", retCode);
        }
    } else {
        NSLog(@"Your SQLite database is not compiled to be threadsafe.");
    }

    sqlite3 *newDBconnection;

    // Open the …