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[ Main Table Of Contents | Table Of Contents | Keyword Index | Categories | Modules | Applications ]

NAME

cksum - Calculate a cksum(1) compatible checksum

Table Of Contents

SYNOPSIS

package require Tcl 8.2
package require cksum ?1.1.4?

::crc::cksum ?-format format? ?-chunksize size? [ -channel chan | -filename file | string ]
::crc::CksumInit
::crc::CksumUpdate token data
::crc::CksumFinal token

DESCRIPTION

This package provides a Tcl implementation of the cksum(1) algorithm based upon information provided at in the GNU implementation of this program as part of the GNU Textutils 2.0 package.

COMMANDS

OPTIONS

PROGRAMMING INTERFACE

The cksum package implements the checksum using a context variable to which additional data can be added at any time. This is expecially useful in an event based environment such as a Tk application or a web server package. Data to be checksummed may be handled incrementally during a fileevent handler in discrete chunks. This can improve the interactive nature of a GUI application and can help to avoid excessive memory consumption.

EXAMPLES

% crc::cksum "Hello, World!"
2609532967

% crc::cksum -format 0x%X "Hello, World!"
0x9B8A5027

% crc::cksum -file cksum.tcl
1828321145

% set tok [crc::CksumInit]
% crc::CksumUpdate $tok "Hello, "
% crc::CksumUpdate $tok "World!"
% crc::CksumFinal $tok
2609532967

AUTHORS

Pat Thoyts

Bugs, Ideas, Feedback

This document, and the package it describes, will undoubtedly contain bugs and other problems. Please report such in the category crc of the Tcllib Trackers. 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.

SEE ALSO

crc32(n), sum(n)

KEYWORDS

checksum, cksum, crc, crc32, cyclic redundancy check, data integrity, security

CATEGORY

Hashes, checksums, and encryption

COPYRIGHT

Copyright © 2002, Pat Thoyts