NAME

       tcl::transform::adler32 - Adler32 transformation

SYNOPSIS

       package require Tcl  8.6

       package require tcl::transform::core  ?1?

       package require tcl::transform::adler32  ?1?

       ::tcl::transform::adler32 chan -option value...

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DESCRIPTION

       The  tcl::transform::adler32  package provides a command creating a channel transformation
       which passes the read and written bytes through unchanged (like tcl::transform::identity),
       but  additionally  continuously computes the adler32 checksums of the data it has seen for
       each direction and stores them in Tcl variables specified at construction time.

       Related transformations in this module are tcl::transform::counter, 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::adler32 chan -option value...
              This command creates an adler32 checksumming 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 adler32 checksum  of  the
                     data read from the channel.

                     If not specified, or the empty string, the checksum 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 adler32 checksum of the
                     data written to the channel.

                     If not specified, or the empty string, the checksum 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

       adler32, channel transformation, checksum, reflected  channel,  tip  230,  transformation,
       virtual channel

CATEGORY

       Channels

COPYRIGHT

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