c/c++语言开发共享FSEvents C ++示例

是的，它可以用C.你应该寻找内核队列。

这是一个观察目录的小样本：

#include  // for errno #include  // for O_RDONLY #include  // for fprintf() #include  // for EXIT_SUCCESS #include  // for strerror() #include  // for kqueue() etc. #include  // for close() int main (int argc, const char *argv[]) { int kq = kqueue (); // dir name is in argv[1], NO checks for errors here int dirfd = open (argv[1], O_RDONLY); struct kevent direvent; EV_SET (&direvent, dirfd, EVFILT_VNODE, EV_ADD | EV_CLEAR | EV_ENABLE, NOTE_WRITE, 0, (void *)dirname); kevent(kq, &direvent, 1, NULL, 0, NULL); // Register interest in SIGINT with the queue. The user data // is NULL, which is how we'll differentiate between // a directory-modification event and a SIGINT-received event. struct kevent sigevent; EV_SET (&sigevent, SIGINT, EVFILT_SIGNAL, EV_ADD | EV_ENABLE, 0, 0, NULL); // kqueue event handling happens after the legacy API, so make // sure it doesn eat the signal before the kqueue can see it. signal (SIGINT, SIG_IGN); // Register the signal event. kevent(kq, &sigevent, 1, NULL, 0, NULL); while (1) { // camp on kevent() until something interesting happens struct kevent change; if (kevent(kq, NULL, 0, &change, 1, NULL) == -1) { exit(1); } // The signal event has NULL in the user data. Check for that first. if (change.udata == NULL) { break; } else { // udata is non-null, so it's the name of the directory printf ("%sn", (char*)change.udata); } } close (kq); return 0; } 

细节可以在ch中找到。 Mark Dalrymple的“高级Mac OSX编程”16（kqueues和FSEvents）。 有关kqueues的* BSD文档中可以找到其他信息。

或者使用FSEvents中的这个API（它主要是基于C的）。

 FSEventStreamRef FSEventStreamCreate (CFAllocatorRef allocator, FSEventStreamCallback callback, FSEventStreamContext *context, CFArrayRef pathsToWatch, FSEventStreamEventId sinceWhen, CFTimeInterval latency, FSEventStreamCreateFlags flags); 

使用pure-C回调创建FSEvents事件流。

然后使用。将此事件流附加到您的runloop

 void FSEventStreamScheduleWithRunLoop (FSEventStreamRef streamRef, CFRunLoopRef runLoop, CFStringRef runLoopMode); 

是的，在这里您可能应该使用一行Obj-C来获取RunLoop句柄：使用-getCFRunLoop从NSRunLoop获取CFRunLoop

 CFRunLoop* loopRef = [[NSRunLoop currentRunLoop] getCFRunLoop]; 

或使用纯C调用

 CFRunLoop* loopRef = CFRunLoopGetCurrent(); 

使用启动事件流

 Boolean FSEventStreamStart (FSEventStreamRef streamRef); 

使用停止事件流

 void FSEventStreamStop (FSEventStreamRef streamRef); 

然后使用以下方法从runloop中取消计划：

 void FSEventStreamUnscheduleFromRunLoop (FSEventStreamRef streamRef, CFRunLoopRef runLoop, CFStringRef runLoopMode); 

使流无效（清理）：

 void FSEventStreamInvalidate (FSEventStreamRef streamRef); 

希望这会让你开始。

需要了解更多c/c++开发分享FSEvents C ++示例，也可以关注C/ C++技术分享栏目—计算机技术网(www.ctvol.com)!