Wed May 21 21:30:20 Paris, Madrid (heure d?t) 2014
Trace back: can't read "base_windows": no such variable
    while executing
"llength $base_windows"
    (procedure "Geometry::TileWindows" line 29)
    invoked from within
"Geometry::TileWindows Horizontally"
    (menu invoke)
  <2: ::tkerror {can't read "base_windows": no such variable}
  <1: ::bgerror {can't read "base_windows": no such variable}
