Class: Inotify

Inherits:

Object

Object
Inotify

show all

Extended by:: FFI::Library

Defined in:: lib/inotify/inotify_native.rb

Overview

The Inotify class is a simple wrapper around the inotify functionality provided by the OS

Defined Under Namespace

Classes: Event, EventStruct

Constant Summary collapse

VERSION = :nodoc:

"1.0.2"

MAX_NAME_SIZE = The maximum supported size of the name argument in the inotify event structure

ACCESS = File was accessed (read) (*)

0x00000001

MODIFY = File was modified (*)

0x00000002

ATTRIB = Metadata changed, e.g., permissions, timestamps, extended attributes, link count (since Linux 2.6.25), UID, GID, etc. (*)

0x00000004

CLOSE_WRITE = File opened for writing was closed (*)

0x00000008

CLOSE_NOWRITE = File not opened for writing was closed (*)

0x00000010

OPEN = File was opened (*)

0x00000020

MOVED_FROM = File moved out of watched directory (*)

0x00000040

MOVED_TO = File moved into watched directory (*)

0x00000080

CREATE = File/directory created in watched directory (*)

0x00000100

DELETE = File/directory deleted from watched directory (*)

0x00000200

DELETE_SELF = Watched file/directory was itself deleted

0x00000400

MOVE_SELF = Watched file/directory was itself moved

0x00000800

UNMOUNT = File system containing watched object was unmounted

0x00002000

Q_OVERFLOW = Event queue overflowed (wd is -1 for this event)

0x00004000

IGNORED = Watch was removed explicitly (inotify_rm_watch(2)) or automatically (file was deleted, or file system was unmounted)

0x00008000

ONLYDIR = (since Linux 2.6.15) Only watch pathname if it is a directory

0x01000000

DONT_FOLLOW = (since Linux 2.6.15) Don’t dereference pathname if it is a symbolic link

0x02000000

EXCL_UNLINK = (since Linux 2.6.36) By default, when watching events on the children of a directory, events are generated for children even after they have been unlinked from the directory. This can result in large numbers of uninteresting events for some applications (e.g., if watching /tmp, in which many applications create temporary files whose names are immediately unlinked). Specifying IN_EXCL_UNLINK changes the default behavior, so that events are not generated for children after they have been unlinked from the watched directory.

0x04000000

MASK_ADD = Add (OR) events to watch mask for this pathname if it already exists (instead of replacing mask)

0x20000000

ISDIR = Subject of this event is a directory

0x40000000

ONESHOT = Monitor pathname for one event, then remove from watch list

0x80000000

CLOSE = Both of the close events

(CLOSE_WRITE | CLOSE_NOWRITE)

MOVE = Both of the move events

(MOVED_FROM | MOVED_TO)

ALL_EVENTS = All of the events

(ACCESS | MODIFY | ATTRIB | CLOSE_WRITE | \
CLOSE_NOWRITE | OPEN | MOVED_FROM | \
MOVED_TO | CREATE | DELETE | DELETE_SELF | MOVE_SELF)

Instance Method Summary collapse

#add_watch(pathname, mask) ⇒ Object

add_watch() adds a new watch, or modifies an existing watch, for the file whose location is specified in pathname; the caller must have read permission for this file.
#close ⇒ Object

close() stops the processing of events and closes the inotify instance in the OS.
#each_event ⇒ Object

each_event() provides an easy way to loop over all events as they occur.
#initialize ⇒ Inotify constructor

When creating a new instance of this class, an inotify instance is created in the OS.
#read_event ⇒ Object

read_event() attempts to read the next inotify event from the OS.
#rm_watch(wd) ⇒ Object

rm_watch() removes the watch associated with the watch descriptor wd.

Constructor Details

#initialize ⇒ `Inotify`

When creating a new instance of this class, an inotify instance is created in the OS.

# File 'lib/inotify/inotify_native.rb', line 88

def initialize # :nodoc:
  @fd = self.inotify_init
  @io = FFI::IO.for_fd(@fd)
end

Instance Method Details

#add_watch(pathname, mask) ⇒ `Object`

add_watch() adds a new watch, or modifies an existing watch, for the file whose location is specified in pathname; the caller must have read permission for this file. The events to be monitored for pathname are specified in the mask bit-mask argument. On success, inotify_add_watch() returns a nonnegative watch descriptor (wd), or -1 if an error occurred.



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# File 'lib/inotify/inotify_native.rb', line 99

def add_watch(pathname, mask)
  self.inotify_add_watch(@fd, pathname, mask)
end

#close ⇒ `Object`

close() stops the processing of events and closes the inotify instance in the OS



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# File 'lib/inotify/inotify_native.rb', line 111

def close
  self.inotify_close(@fd)
end

#each_event ⇒ `Object`

each_event() provides an easy way to loop over all events as they occur

# File 'lib/inotify/inotify_native.rb', line 116

def each_event
  loop do
    ready = IO.select([@io], nil, nil, nil)
    event = self.read_event
    yield event
  end
end

#read_event ⇒ `Object`

read_event() attempts to read the next inotify event from the OS

# File 'lib/inotify/inotify_native.rb', line 125

def read_event # :nodoc:
  buf = FFI::Buffer.alloc_out(EventStruct.size + MAX_NAME_SIZE, 1, false)
  ev = EventStruct.new(buf)
  n = self.read(@fd, buf, buf.total)
  Event.new(ev, buf)
end

#rm_watch(wd) ⇒ `Object`

rm_watch() removes the watch associated with the watch descriptor wd. On success, returns zero, or -1 if an error occurred.



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# File 'lib/inotify/inotify_native.rb', line 105

def rm_watch(wd)
  self.inotify_rm_watch(@fd, wd)
end

Class: Inotify

Overview

Defined Under Namespace

Constant Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Inotify

Instance Method Details

#add_watch(pathname, mask) ⇒ Object

#close ⇒ Object

#each_event ⇒ Object