set numarchive 1
   set nomarchive "lesxml[format "%03d" $numarchive].tar"

   while { [file exists $nomarchive] } {
       set numarchive [incr numarchive]
       set nomarchive "lesxml[format "%03d" $numarchive].tar"
   } ; # fin de tant que

   # unix :

   set  specfic "*.xml"
   set  rc [exec echo tar -cvf $nomarchive $specfic > archauto ]
   set  rc [exec sh archauto ]

   #  dos :

   #   set  specfic "*\\*.xml"
   #   set  rc [exec tar -cvf $nomarchive $specfic ]   set  rc [exec echo tar -cvf $nomarchive $specfic > archauto ]

   label .okarch -text " archivage des fichiers $specfic dans $nomarchive terminée." \
                 -fg   "blue" -bg   "yellow" -font { Arial 20 bold }
   pack .okarch
   after 5000 exit