使用epoll + inotify监控文件

#include <sys/epoll.h>
#include <fcntl.h>
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <sys/inotify.h>

#define EVENT_SIZE  ( sizeof (struct inotify_event) )
#define BUF_LEN     ( 1024 * ( EVENT_SIZE + 16 ) )

int
main (int argc, char *argv[])
{
  int i, epfd, nfds, fd;
  int wd;
  int length;

  char buffer[BUF_LEN];
  struct epoll_event ev, events[20];
  epfd = epoll_create (256);
  fd = inotify_init ();
  wd = inotify_add_watch (fd, "/home/cc/tmp",
                          IN_MODIFY | IN_CREATE | IN_DELETE);

  ev.data.fd = fd;
  ev.events = EPOLLIN | EPOLLET;

  epoll_ctl (epfd, EPOLL_CTL_ADD, fd, &ev);

  for (;;)
    {
      nfds = epoll_wait (epfd, events, 20, 500);

      for (i = 0; i < nfds; ++i)
        {
          if (events[i].data.fd == fd)

            {
              length = read (fd, buffer, BUF_LEN);

              if (length < 0)
                {
                  perror ("read");
                }

              while (i < length)
                {
                  struct inotify_event *event =
                    (struct inotify_event *) &buffer[i];
                  if (event->len)
                    {
                      if (event->mask & IN_CREATE)
                        {
                          if (event->mask & IN_ISDIR)
                            {
                              printf ("The directory %s was created.\n",
                                      event->name);
                            }
                          else
                            {printf ("The file %s was created.\n",
                                      event->name);
                            }
                        }
                      else if (event->mask & IN_DELETE)
                        {
                          if (event->mask & IN_ISDIR)
                            {
                              printf ("The directory %s was deleted.\n",
                                      event->name);
                            }
                          else
                            {
                              printf ("The file %s was deleted.\n",
                                      event->name);
                            }
                        }
                      else if (event->mask & IN_MODIFY)
                        {
                          if (event->mask & IN_ISDIR)
                            {
                              printf ("The directory %s was modified.\n",
                                      event->name);
                            }
                          else
                            {
                              printf ("The file %s was modified.\n",
                                      event->name);
                            }
                        }
                    }
                  i += EVENT_SIZE + event->len;
                }
        
            }


        }

    }



  return 0;
}