History diff of LiveCDの歩き方 vs current(No. 5)

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The deleted line is THIS COLOR.
kqueue / kevent というものを初めて使ってみた；
 #include <stdio.h>
 
 #include <sys/types.h>
 #include <dirent.h>
 
 #include <sys/types.h>
 #include <sys/event.h>
 #include <sys/time.h>
 
 main () {
  /*
   *  Open current working directory
   */
   DIR *d;
   int dfd;
   int err;
 
   if (!(d = opendir("."))) {
     perror("opendir");
     exit(1);
   }
 
  /*
   *  create and register kernel event queue
   */
   int kq;
   struct kevent kev;
 
   if ((kq = kqueue()) == -1) {
     perror("kqueue");
     closedir(d);
     exit(1);
   }
 
   EV_SET(&kev, dirfd(d), EVFILT_VNODE, EV_ADD|EV_CLEAR, NOTE_WRITE, 0, NULL);
 
   if (kevent(kq, &kev, 1, NULL, 0, NULL) < 0) {
     perror("kevent on register");
     closedir(d);
     exit(1);
   }
 
   int retval;
 
  /*
   *  then go monitoring
   */
   if (0 < kevent(kq, NULL, 0, &kev, 1, NULL)) {
     printf("dir changed.\n");
   } else {
     perror("kevent on nofity");
     closedir(d);
     exit(1);
   }
 
  /*
   *  normal exit
   */
   closedir(d);
   exit(0);
 }