tcl::transform::crc32 -
Crc32 transformation
package require Tcl 8.6
package require tcl::transform::core ? 1 ?
package require tcl::transform::crc32 ? 1 ?
::tcl::transform::crc32 chan -option value...
The tcl::transform::crc32 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 crc32 checksums of the data it
has seen for each direction and stores them in Tcl variables specified
at construction time. The checksum in question is zlib's crc32.
Related transformations in this module are
tcl::transform::adler32,
tcl::transform::counter,
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.
-
::tcl::transform::crc32 chan -option value...
-
This command creates a crc32 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
crc32 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
crc32 checksum of the data written to the channel.
If not specified, or the empty string, the checksum of the
write direction is not saved.
This document, and the package it describes, will undoubtedly contain
bugs and other problems.
Please report such in the category
virtchannel of the
http://sourceforge.net/tracker/?group_id=12883.
Please also report any ideas for enhancements you may have for either
package and/or documentation.
crc32, checksum, transformation, channel transformation, virtual channel, reflected channel, tip 230