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Kernel v2.6.25-rc4 /Documentation/dnotify.txt

Filename:/Documentation/dnotify.txt
Lines Added:0
Lines Deleted:99
Also changed in: (Previous) 2.6.25-rc3  2.6.25-rc2  2.6.25-rc1  2.6.24-git22  2.6.24-git21  2.6.24-git20 
(Following) 2.6.25-rc5  2.6.25-rc6  2.6.25-rc7  2.6.25-rc8  2.6.25-rc9  2.6.25 

Location
[  2.6.25-rc4
  [  Documentation
     o  dnotify.txt

Patch

diff --git a/Documentation/dnotify.txt b/Documentation/dnotify.txt
deleted file mode 100644
index 6984fca..0000000
--- a/Documentation/dnotify.txt
+++ /dev/null
@@ -1,99 +0,0 @@
-      Linux Directory Notification
-      ============================
-
-      Stephen Rothwell <sfr@canb.auug.org.au>
-
-The intention of directory notification is to allow user applications
-to be notified when a directory, or any of the files in it, are changed.
-The basic mechanism involves the application registering for notification
-on a directory using a fcntl(2) call and the notifications themselves
-being delivered using signals.
-
-The application decides which "events" it wants to be notified about.
-The currently defined events are:
-
-   DN_ACCESS   A file in the directory was accessed (read)
-   DN_MODIFY   A file in the directory was modified (write,truncate)
-   DN_CREATE   A file was created in the directory
-   DN_DELETE   A file was unlinked from directory
-   DN_RENAME   A file in the directory was renamed
-   DN_ATTRIB   A file in the directory had its attributes
-         changed (chmod,chown)
-
-Usually, the application must reregister after each notification, but
-if DN_MULTISHOT is or'ed with the event mask, then the registration will
-remain until explicitly removed (by registering for no events).
-
-By default, SIGIO will be delivered to the process and no other useful
-information.  However, if the F_SETSIG fcntl(2) call is used to let the
-kernel know which signal to deliver, a siginfo structure will be passed to
-the signal handler and the si_fd member of that structure will contain the
-file descriptor associated with the directory in which the event occurred.
-
-Preferably the application will choose one of the real time signals
-(SIGRTMIN + <n>) so that the notifications may be queued.  This is
-especially important if DN_MULTISHOT is specified.  Note that SIGRTMIN
-is often blocked, so it is better to use (at least) SIGRTMIN + 1.
-
-Implementation expectations (features and bugs :-))
----------------------------
-
-The notification should work for any local access to files even if the
-actual file system is on a remote server.  This implies that remote
-access to files served by local user mode servers should be notified.
-Also, remote accesses to files served by a local kernel NFS server should
-be notified.
-
-In order to make the impact on the file system code as small as possible,
-the problem of hard links to files has been ignored.  So if a file (x)
-exists in two directories (a and b) then a change to the file using the
-name "a/x" should be notified to a program expecting notifications on
-directory "a", but will not be notified to one expecting notifications on
-directory "b".
-
-Also, files that are unlinked, will still cause notifications in the
-last directory that they were linked to.
-
-Configuration
--------------
-
-Dnotify is controlled via the CONFIG_DNOTIFY configuration option.  When
-disabled, fcntl(fd, F_NOTIFY, ...) will return -EINVAL.
-
-Example
--------
-
-   #define _GNU_SOURCE   /* needed to get the defines */
-   #include <fcntl.h>   /* in glibc 2.2 this has the needed
-                  values defined */
-   #include <signal.h>
-   #include <stdio.h>
-   #include <unistd.h>
-   
-   static volatile int event_fd;
-   
-   static void handler(int sig, siginfo_t *si, void *data)
-   {
-      event_fd = si->si_fd;
-   }
-   
-   int main(void)
-   {
-      struct sigaction act;
-      int fd;
-      
-      act.sa_sigaction = handler;
-      sigemptyset(&act.sa_mask);
-      act.sa_flags = SA_SIGINFO;
-      sigaction(SIGRTMIN + 1, &act, NULL);
-      
-      fd = open(".", O_RDONLY);
-      fcntl(fd, F_SETSIG, SIGRTMIN + 1);
-      fcntl(fd, F_NOTIFY, DN_MODIFY|DN_CREATE|DN_MULTISHOT);
-      /* we will now be notified if any of the files
-         in "." is modified or new files are created */
-      while (1) {
-         pause();
-         printf("Got event on fd=%d\n", event_fd);
-      }
-   }


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