#include <sys/epoll.h>
int epoll_create(int size);
##參數(shù)
- size：監(jiān)聽的事件數(shù)目；

#include <sys/epoll.h>
int epoll_ctl(int epfd, int op, int fd, struct epoll_event *event);
## 參數(shù)
- epfd：epoll_create()返回值；
- op：執(zhí)行的操作。包括EPOLL_CTL_ADD、EPOLL_CTL_MOD、EPOLL_CTL_DEL；
- fd：文件描述符；
- event：結構體epoll_event的指針。
#### 結構體epoll_event
typedef union epoll_data
{
 	void *ptr; /* Pointer to user-defind data */
 	int fd; /* File descriptor */
 	uint32_t u32; /* 32-bit integer */
 	uint64_t u64; /* 64-bit integer */
} epoll_data_t;
struct epoll_event
{
 	uint32_t events; /* epoll events(bit mask) */
 	epoll_data_t data; /* User data */
};

#include <sys/epoll.h>
int epoll_wait(int epfd, struct epoll_event *events,
                      int maxevents, int timeout);
## 參數(shù)：
- epfd：epoll_create()返回值；
- events：evlist所指向的結構體數(shù)組中返回的是有關就緒態(tài)文件描述符的信息，數(shù)組evlist的空間由調(diào)用者負責申請；
- maxevents：指定所evlist數(shù)組里包含的元素個數(shù)；
- timeout：確定epoll_wait()的阻塞行為。<0：一直阻塞，0：執(zhí)行一次非阻塞式地檢查，>0：調(diào)用將阻塞至多timeout毫秒；

#include <sys/inotify.h>
int inotify_init(void);
## 返回值
- 返回文件描述符

#include <sys/inotify.h>
int inotify_add_watch(int fd, const char *pathname, uint32_t mask);
## 參數(shù)
- fd: inotify_init的返回值;
- pathname: 目錄或文件路徑;
- mask: 監(jiān)控的事件類型;
## 返回值
- 針對pathname的watch描述符

#include <sys/inotify.h>
int inotify_rm_watch(int fd, int wd);
## 參數(shù)值
- fd: inotify_init的返回值;
- wd: inotify_add_watch的返回值;

#include <iostream>
#include <thread>
#include <sys/inotify.h>
#include <sys/epoll.h>
#include <unistd.h>
using namespace std;
#define   INOTIFY_FDS           200
#define   INOTIFY_EVENT_SIZE    (sizeof(struct inotify_event))
#define   INOTIFY_BUF_LEN       (1024*(INOTIFY_EVENT_SIZE + 16))
int main()
{
	// inotify初始化
	int inotifyId = inotify_init();
	if (-1 == inotifyId)
	{
		cout << "inotify_init failed" << endl;
		return -1;
	}
	// 創(chuàng)建epoll句柄
	int epfd = epoll_create(INOTIFY_FDS);
	if (-1 == epfd)
	{
		cout << "epoll_create failed" << endl;
		return -1;
	}
	// 注冊epoll事件
	struct epoll_event ev;
	ev.data.fd = inotifyId;                
	ev.events = EPOLLIN | EPOLLET;      
	int ret = epoll_ctl(epfd, EPOLL_CTL_ADD, inotifyId, &ev);
	if (-1 == ret)
	{
		cout << "epoll_ctl failed" << endl;
		return -1;
	}
	// 添加監(jiān)聽對象
	const char* pathMame = "/home/inotify/dir/";
	int watchFd = inotify_add_watch(inotifyId, pathMame, IN_MODIFY | IN_CREATE | IN_DELETE);
	if (watchFd < 0)
	{
		cout << "inotify_add_watch failed" << endl;
		return -1;
	}
	// 啟動線程
	std::thread func = std::thread([&]() {
		// 循環(huán)監(jiān)聽事件
		char buf[INOTIFY_BUF_LEN] = { 0, };
		struct epoll_event events[20];
		while (1)
		{
			int nfds = epoll_wait(epfd, events, 20, 1000);
			for (int i = 0; i < nfds; ++i)
			{
				if (events[i].data.fd != inotifyId)
				{
					continue;
				}
				int length = read(inotifyId, buf, INOTIFY_BUF_LEN);
				if (length < 0)
				{
					// error
					continue;
				}
				int pos = 0;
				while (pos < length)
				{
					struct inotify_event* event = (struct inotify_event*)&buf[pos];
					if (event->len)
					{
                        // 此處(event->wd == watchFd)
						if (event->mask & IN_CREATE)
						{
							if (event->mask & IN_ISDIR)
							{
								// dir create
								cout << "dir create" << endl;
							}
							else
							{
								// file create
								cout << "file create" << endl;
							}
						}
						else if (event->mask & IN_DELETE)
						{
							if (event->mask & IN_ISDIR)
							{
								// dir delete
								cout << "dir delete" << endl;
							}
							else
							{
								// file delete
								cout << "file delete" << endl;
							}
						}
						else if (event->mask & IN_MODIFY)
						{
							if (event->mask & IN_ISDIR)
							{
								// dir modify
								cout << "dir modify" << endl;
							}
							else
							{
								// file modify
								cout << "file modify" << endl;
							}
						}
					}
					pos += INOTIFY_EVENT_SIZE + event->len;
				}
			}
			// 1s更新一次
			sleep(1);
		}
	});
	func.join();
	while (1)
	{
		// 僅作事件循環(huán)
		sleep(2);
	}
	inotify_rm_watch(inotifyId, watchFd);
	close(epfd);
	close(inotifyId);
	return 0;
}