tcl::chan::events(3tcl)Reflected/virtual channel supportcl::chan::events(3tcl)
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NAME
tcl::chan::events - Event support for reflected/virtual channels
SYNOPSIS
package require Tcl 8.5
package require TclOO
package require tcl::chan::core ?1?
package require tcl::chan::events ?1?
::tcl::chan::events objectName
objectName finalize thechannel
objectName watch thechannel eventmask
objectName allow eventname...
objectName disallow eventname...
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DESCRIPTION
The tcl::chan::events package provides a TclOO class implementing com-
mon behaviour needed by virtually every reflected or virtual channel
supporting event driven IO. It is a sub-class of tcl::chan::core, in-
heriting all of its behaviour.
This class expects to be used as either superclass of a concrete chan-
nel class, or to be mixed into such a class.
CLASS API
::tcl::chan::events objectName
This command creates a new channel event core object with an as-
sociated global Tcl command whose name is objectName. This com-
mand may be used to invoke various operations on the object, as
described in the section for the Instance API.
INSTANCE API
The API of channel event core instances provides only four methods, two
corresponding to channel handler commands (For reference see TIP 219
[http:/tip.tcl.tk/219]), and the other two for use by sub-classes to
control event generation. They former expect to be called from which-
ever object instance the channel event core was made a part of.
objectName finalize thechannel
This method implements standard behaviour for the finalize
method of channel handlers. It overrides the behaviour inherited
from tcl::chan::core and additionally disables any and all event
generation before destroying itself.
objectName watch thechannel eventmask
This method implements standard behaviour for the watch method
of channel handlers. Called by the IO system whenever the inter-
est in event changes it updates the instance state to activate
and/or suppress the generation of the events of (non-)interest.
objectName allow eventname...
objectName disallow eventname...
These two methods are exported to sub-classes, so that their in-
stances can notify their event core of the events the channel
they implement can (allow) or cannot (disallow) generate. To-
gether with the information about the events requested by Tcl's
IO system coming in through the watch method the event core is
able to determine which events it should (not) generate and act
accordingly.
BUGS, IDEAS, FEEDBACK
This document, and the package it describes, will undoubtedly contain
bugs and other problems. Please report such in the category virtchan-
nel of the Tcllib Trackers [http://core.tcl.tk/tcllib/reportlist].
Please also report any ideas for enhancements you may have for either
package and/or documentation.
When proposing code changes, please provide unified diffs, i.e the out-
put of diff -u.
Note further that attachments are strongly preferred over inlined
patches. Attachments can be made by going to the Edit form of the
ticket immediately after its creation, and then using the left-most
button in the secondary navigation bar.
KEYWORDS
event management, reflected channel, tip 219, virtual channel
CATEGORY
Channels
COPYRIGHT
Copyright (c) 2009 Andreas Kupries <andreas_kupries@users.sourceforge.net>
tcllib 1 tcl::chan::events(3tcl)