[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>
diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
index 5b5f434..ce19a2a 100644
--- a/include/linux/sysctl.h
+++ b/include/linux/sysctl.h
@@ -61,7 +61,8 @@
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 @@
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
{