'\"
'\" Generated from file 'observe\&.man' by tcllib/doctools with format 'nroff'
'\" Copyright (c) 2009 Andreas Kupries <andreas_kupries@users\&.sourceforge\&.net>
'\"
.TH "tcl::transform::observe" n 1 tcllib "Reflected/virtual channel support"
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.BS
.SH NAME
tcl::transform::observe \- Observer transformation, stream copy
.SH SYNOPSIS
package require \fBTcl  8\&.6\fR
.sp
package require \fBtcl::transform::core  ?1?\fR
.sp
package require \fBtcl::transform::observe  ?1?\fR
.sp
\fB::tcl::transform::observe\fR \fIchan\fR \fIlogw\fR \fIlogr\fR
.sp
.BE
.SH DESCRIPTION
.PP
The \fBtcl::transform::observer\fR package provides a command
creating a channel transformation which passes the read and written
bytes through unchanged (like \fBtcl::transform::identity\fR), but
additionally copies the data it has seen for each direction into
channels specified at construction time\&.
.PP
Related transformations in this module are
\fBtcl::transform::adler32\fR,
\fBtcl::transform::counter\fR,
\fBtcl::transform::crc32\fR, and
\fBtcl::transform::identity\fR\&.
.PP
The internal \fBTclOO\fR class implementing the transform
handler is a sub-class of the \fBtcl::transform::core\fR
framework\&.
.SH API
.TP
\fB::tcl::transform::observe\fR \fIchan\fR \fIlogw\fR \fIlogr\fR
This command creates an observer transformation on top of the channel
\fIchan\fR and returns its handle\&. The channel handles \fIlogr\fR and
\fIlogw\fR are there the data is copied to\&.
.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\&.
.SH KEYWORDS
channel transformation, observer, reflected channel, stream copy, tip 230, transformation, virtual channel
.SH CATEGORY
Channels
.SH COPYRIGHT
.nf
Copyright (c) 2009 Andreas Kupries <andreas_kupries@users\&.sourceforge\&.net>

.fi