/usr/share/blt2.5/demos/tabset4.tcl is in blt-demo 2.5.3+dfsg-1.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109  | #!/usr/bin/wish8.6
package require BLT
# --------------------------------------------------------------------------
# Starting with Tcl 8.x, the BLT commands are stored in their own 
# namespace called "blt".  The idea is to prevent name clashes with
# Tcl commands and variables from other packages, such as a "table"
# command in two different packages.  
#
# You can access the BLT commands in a couple of ways.  You can prefix
# all the BLT commands with the namespace qualifier "blt::"
#  
#    blt::graph .g
#    blt::table . .g -resize both
# 
# or you can import all the command into the global namespace.
#
#    namespace import blt::*
#    graph .g
#    table . .g -resize both
#
# --------------------------------------------------------------------------
if { $tcl_version >= 8.0 } {
    namespace import blt::*
    namespace import -force blt::tile::*
}
source scripts/demo.tcl
#bltdebug 100
source scripts/stipples.tcl
tabset .t \
    -samewidth yes \
    -side left \
    -textside bottom \
    -textside top \
    -bg red \
    -tiers 1 \
    -scrollincrement 10 \
    -scrollcommand { .s set } \
    -rotate 0 \
    -selectcommand {  MakePhoto %W %n } 
scrollbar .s -command { .t view } -orient horizontal
 
option clear
option add *Tabset.Tab.font -*-helvetica-bold-r-*-*-10-*-*-*-*-*-*-*
set files [glob ./images/*.gif]
set files [lsort $files]
#set vertFilter sinc
#set horzFilter sinc
set vertFilter none
set horzFilter none
proc ResizePhoto { src dest maxSize } {
    set maxSize [winfo fpixels . $maxSize]
    set w [image width $src]
    set h [image height $src]
    set sw [expr double($maxSize) / $w]
    set sh [expr double($maxSize) / $h]
    set s [expr min($sw, $sh)]
    set w [expr round($s * $w)]
    set h [expr round($s * $h)]
    $dest configure -width $w -height $h
    
    global horzFilter vertFilter
    winop image resample $src $dest $horzFilter $vertFilter
}
image create photo src
image create photo dest
label .t.label -image dest -bg purple
proc MakePhoto { w name } {
    set file ./images/$name.gif
    src configure -file $file
    set width [$w tab pagewidth]
    set height [$w tab pageheight]
    if { $width < $height } {
	ResizePhoto src dest $width
    } else {
	ResizePhoto src dest $height
    }
    .t tab dockall
    .t tab configure $name -window .t.label -padx 4m -pady 4m -fill both
}
table . \
    .t 0,0 -fill both \
    .s 1,0 -fill x 
table configure . r1 -resize none
focus .t
foreach f $files {
    src configure -file $f
    set f [file tail [file root $f]]
    set thumb [image create photo]
    ResizePhoto src $thumb 0.5i
    .t insert end $f -image $thumb -fill both
}
.t focus 0
.t invoke 0
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