守护进程知道用户何时登录MAC

Question

我有一个守护进程(用Obj C编写)运行,我想在一些用户登录时执行一些操作.守护进程是否可以知道特定用户何时登录或退出OSX？登录时是否会抛出任何通知？我想避免使用Log in Item或Launch Agent.而且我还想避免轮询定时器来检查登录用户.

Answer 1

使用SCDynamicStoreCopyConsoleUser得到控制台的用户名.

CFStringRef  consoleUserName = nil;
uid_t        uid;
gid_t        gid;
consoleUserName = SCDynamicStoreCopyConsoleUser(NULL, &uid, &gid);

存储consoleUserName在某个成员变量中.现在创建一个会话,以使用系统配置服务器维护的动态存储进行交互SCDynamicStoreCreate

     SCDynamicStoreRef   store;
     CFStringRef         key;
     CFArrayRef          keys;
     CFRunLoopSourceRef  rls;
     store = SCDynamicStoreCreate(
                                     NULL, 
                                     CFSTR("com.apple.dts.ConsoleUser"), 
                                     callBackFunction, 
                                     NULL
                                     );

    // Set it up to notify us when the console user value changes.

    key = SCDynamicStoreKeyCreateConsoleUser(NULL);
    assert(key != NULL);

    keys = CFArrayCreate(NULL, (const void **) &key, 1, &kCFTypeArrayCallBacks);
    //assert(keys != NULL);

    success = SCDynamicStoreSetNotificationKeys(store, keys, NULL);
    //assert(success);

    // Add it to the runloop.

    rls = SCDynamicStoreCreateRunLoopSource(NULL, store, 0);
   // assert(rls != NULL);

    CFRunLoopAddSource(CFRunLoopGetCurrent(), rls, kCFRunLoopDefaultMode);


    mConsoleUserName = CopyCurrentConsoleUsername(store);
    CFRunLoopRun();

    CFRunLoopSourceInvalidate(rls);
    CFRelease(rls);
    CFRelease(keys);
    CFRelease(key);
    CFRelease(store);   

实现callBackFunction功能.当控制台用户值更改时,您将收到回调.

static void callBackFunction(
                               SCDynamicStoreRef    store,
                               CFArrayRef          changedKeys,
                               void *              info
                               )
{
    CFStringRef         currentConsoleUser;
    Boolean             didChange;

    // Get the current console user.

    currentConsoleUser = CopyCurrentConsoleUsername(store);

    if (currentConsoleUser == NULL)
    {
        return;
    }
    didChange = ! CFEqual(storedvalue, currentConsoleUser);
    if (![currentConsoleUser isEqualToString:@"loginwindow"])
    {
      // pass this value to some method
    }
}