no display name and no $DISPLAY environment variable
    while executing
"load /enadisk/commun/linux/local/ActiveTcl-8.6.11/lib/libtk8.6.so Tk"
    ("package ifneeded Tk 8.6.11" script)
    invoked from within
"package require Tk"
    (in namespace eval "::request" script line 3)
    invoked from within
"namespace eval ::request $script"
    ("::try" body line 12)
OUTPUT BUFFER:
#!/usr/local/ActiveTcl/bin/tclsh

 package require Tk

 proc cballoon {w tag text} {
    $w bind $tag  [list cballoon'make $w $text %x %y]
    $w bind all   [list after 1 $w delete cballoon]
 }

 proc cballoon'make {w text x y} {
    if [info exists y] {
        set id [$w create text $x $y -text $text -tag cballoon -anchor sw -justify left]
        foreach {x0 y0 x1 y1} [$w bbox $id] break
        $w create rect $x0 $y0 $x1 $y1 -fill lightyellow -tag cballoon
        $w raise $id
    }
 }

#---------------------------------------------------- Test

 pack [canvas .c]
.c configure -cursor hand2
 set ir [.c create oval 150 150 156 156 -fill red]
 set id [.c create oval 10 10 110 110 -fill red]
 .c create rect 130 30 190 90 -fill blue -tag rect
 cballoon .c $ir "100"
 cballoon .c $id "This is a red oval"
 cballoon .c rect "This is\na blue square"

 bind .  {exec wish $argv0 &; exit}