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 common behaviour needed by virtually
       every reflected or virtual channel supporting event driven IO. It  is  a  sub-class  of  tcl::chan::core,
       inheriting all of its behaviour.

       This  class expects to be used as either superclass of a concrete channel 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 associated global Tcl  command  whose
              name  is  objectName.  This  command  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  whichever  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 interest 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 instances can notify their event core
              of the events the channel they implement can (allow) or cannot (disallow) generate.  Together 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 virtchannel 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 output 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>