NAME

       tcl::transform::counter - Counter transformation

SYNOPSIS

       package require Tcl 8.6 9

       package require tcl::transform::core ?1.1?

       package require tcl::transform::counter ?1.1?

       ::tcl::transform::counter chan -option value...

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DESCRIPTION

       The  tcl::transform::counterr  package  provides a command creating a channel transformation which passes
       the read and written bytes through unchanged (like tcl::transform::identity), but additionally counts the
       bytes it has seen for each direction and stores these counts in Tcl variables specified  at  construction
       time.

       Related    transformations   in   this   module   are   tcl::transform::adler32,   tcl::transform::crc32,
       tcl::transform::identity, and tcl::transform::observe.

       The internal TclOO class implementing the transform handler is a sub-class  of  the  tcl::transform::core
       framework.

API

       ::tcl::transform::counter chan -option value...
              This  command  creates a counter transformation on top of the channel chan and returns its handle.
              The accepted options are

              -read-variable varname
                     The value of the option is the name of a global or namespaced variable, the location  where
                     the transformation has to store the byte count of the data read from the channel.

                     If not specified, or the empty string, the counter of the read direction is not saved.

              -write-variable varname
                     The  value of the option is the name of a global or namespaced variable, the location where
                     the transformation has to store the byte count of the data written to the channel.

                     If not specified, or the empty string, the counter of the write direction is not saved.

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

       channel transformation, counter, reflected channel, tip 230, transformation, virtual channel

CATEGORY

       Channels

COPYRIGHT

       Copyright (c) 2009 Andreas Kupries <andreas_kupries@users.sourceforge.net>

tcllib                                                 1.1                         tcl::transform::counter(3tcl)