Tcl package, [XML] DTD validation extension to [tDOM]. Usage example contributed by [RS]:
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 package require tnc ;# implies tdom

 #---------------------------------------- modified from expat man page
 proc externalEntityRefHandler {base systemId publicId} {
    if {![regexp {^[/a-zA-Z]+:/} $systemId]}  {
	regsub {^[/a-zA-Z]+:} $base {} base
	set basedir [file dirname $base]
	set systemId "[set basedir]/[set systemId]"
    }
    regsub {^[/a-zA-Z]+:} $systemId "" systemId
    set fd [open $systemId]
    list channel $systemId $fd
 }

 set parser [expat -externalentitycommand externalEntityRefHandler\
		   -baseurl "file://[file join [pwd] $file]" \
		   -paramentityparsing always]
 tnc $parser enable
 foreach file [glob $argv] {
    if [file readable $file] {
	catch {$parser parsefile $file} res
	if {$res==""} {set res ok}
	puts $file:$res
	$parser reset
    }
 }
 $parser free
======
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The ''externalEntityRefHandler'' is freely configurable by the user. From tDOM 0.7.5, a convenience proc will be included in the release (planned for mid November 2002).
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!!!!!!
%|[Category Package]|%
!!!!!!