[PATCH] inotify

inotify is intended to correct the deficiencies of dnotify, particularly
its inability to scale and its terrible user interface:

        * dnotify requires the opening of one fd per each directory
          that you intend to watch. This quickly results in too many
          open files and pins removable media, preventing unmount.
        * dnotify is directory-based. You only learn about changes to
          directories. Sure, a change to a file in a directory affects
          the directory, but you are then forced to keep a cache of
          stat structures.
        * dnotify's interface to user-space is awful.  Signals?

inotify provides a more usable, simple, powerful solution to file change
notification:

        * inotify's interface is a system call that returns a fd, not SIGIO.
	  You get a single fd, which is select()-able.
        * inotify has an event that says "the filesystem that the item
          you were watching is on was unmounted."
        * inotify can watch directories or files.

Inotify is currently used by Beagle (a desktop search infrastructure),
Gamin (a FAM replacement), and other projects.

See Documentation/filesystems/inotify.txt.

Signed-off-by: Robert Love <rml@novell.com>
Cc: John McCutchan <ttb@tentacle.dhs.org>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Robert Love
2005-07-12 17:06:03 -04:00
committed by Linus Torvalds
parent bd4c625c06
commit 0eeca28300
24 changed files with 1639 additions and 67 deletions

View File

@@ -61,7 +61,8 @@ enum
CTL_DEV=7, /* Devices */
CTL_BUS=8, /* Busses */
CTL_ABI=9, /* Binary emulation */
CTL_CPU=10 /* CPU stuff (speed scaling, etc) */
CTL_CPU=10, /* CPU stuff (speed scaling, etc) */
CTL_INOTIFY=11 /* Inotify */
};
/* CTL_BUS names: */
@@ -70,6 +71,14 @@ enum
CTL_BUS_ISA=1 /* ISA */
};
/* CTL_INOTIFY names: */
enum
{
INOTIFY_MAX_USER_DEVICES=1, /* max number of inotify device instances per user */
INOTIFY_MAX_USER_WATCHES=2, /* max number of inotify watches per user */
INOTIFY_MAX_QUEUED_EVENTS=3 /* Max number of queued events per inotify device instance */
};
/* CTL_KERN names: */
enum
{