'\"
'\" Generated from file 'events\&.man' by tcllib/doctools with format 'nroff'
'\" Copyright (c) 2009 Andreas Kupries <andreas_kupries@users\&.sourceforge\&.net>
'\"
.TH "tcl::chan::events" n 1\&.1 tcllib "Reflected/virtual channel support"
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.BS
.SH NAME
tcl::chan::events \- Event support for reflected/virtual channels
.SH SYNOPSIS
package require \fBTcl 8\&.5 9\fR
.sp
package require \fBTclOO\fR
.sp
package require \fBtcl::chan::core ?1\&.1?\fR
.sp
package require \fBtcl::chan::events ?1\&.1?\fR
.sp
\fB::tcl::chan::events\fR \fIobjectName\fR
.sp
\fIobjectName\fR \fBfinalize\fR \fIthechannel\fR
.sp
\fIobjectName\fR \fBwatch\fR \fIthechannel\fR \fIeventmask\fR
.sp
\fIobjectName\fR \fBallow\fR \fIeventname\fR\&.\&.\&.
.sp
\fIobjectName\fR \fBdisallow\fR \fIeventname\fR\&.\&.\&.
.sp
.BE
.SH DESCRIPTION
.PP
The \fBtcl::chan::events\fR package provides a \fBTclOO\fR
class implementing common behaviour needed by virtually every
reflected or virtual channel supporting event driven IO\&. It is a
sub-class of \fBtcl::chan::core\fR, inheriting all of its behaviour\&.
.PP
This class expects to be used as either superclass of a concrete
channel class, or to be mixed into such a class\&.
.SH "CLASS API"
.TP
\fB::tcl::chan::events\fR \fIobjectName\fR
This command creates a new channel event core object with an associated
global Tcl command whose name is \fIobjectName\fR\&. This command may
be used to invoke various operations on the object, as described in
the section for the \fBInstance API\fR\&.
.PP
.SH "INSTANCE API"
The API of channel event core instances provides only four methods, two
corresponding to channel handler commands (For reference see
\fITIP 219\fR [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\&.
.TP
\fIobjectName\fR \fBfinalize\fR \fIthechannel\fR
This method implements standard behaviour for the \fBfinalize\fR
method of channel handlers\&. It overrides the behaviour inherited from
\fBtcl::chan::core\fR and additionally disables any and all event
generation before destroying itself\&.
.TP
\fIobjectName\fR \fBwatch\fR \fIthechannel\fR \fIeventmask\fR
This method implements standard behaviour for the \fBwatch\fR
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\&.
.TP
\fIobjectName\fR \fBallow\fR \fIeventname\fR\&.\&.\&.
.TP
\fIobjectName\fR \fBdisallow\fR \fIeventname\fR\&.\&.\&.
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 \fBwatch\fR method the event core is
able to determine which events it should (not) generate and act
accordingly\&.
.PP
.SH "BUGS, IDEAS, FEEDBACK"
This document, and the package it describes, will undoubtedly contain
bugs and other problems\&.
Please report such in the category \fIvirtchannel\fR of the
\fITcllib Trackers\fR [http://core\&.tcl\&.tk/tcllib/reportlist]\&.
Please also report any ideas for enhancements you may have for either
package and/or documentation\&.
.PP
When proposing code changes, please provide \fIunified diffs\fR,
i\&.e the output of \fBdiff -u\fR\&.
.PP
Note further that \fIattachments\fR are strongly preferred over
inlined patches\&. Attachments can be made by going to the \fBEdit\fR
form of the ticket immediately after its creation, and then using the
left-most button in the secondary navigation bar\&.
.SH KEYWORDS
event management, reflected channel, tip 219, virtual channel
.SH CATEGORY
Channels
.SH COPYRIGHT
.nf
Copyright (c) 2009 Andreas Kupries <andreas_kupries@users\&.sourceforge\&.net>

.fi
