Eskil

    # Add a dummy if it does not exist.
    proc addBalloon {args} {}
} else {
    namespace import -force psballoon::addBalloon
}

set debug 0
set diffver "Version 2.0.3+ 2004-06-16"
set thisScript [file join [pwd] [info script]]
set thisDir [file dirname $thisScript]

# Follow any link
set tmplink $thisScript
while {[file type $tmplink] eq "link"} {
    set tmplink [file readlink $tmplink]

        for {set t 0} {$t < $d} {incr t} {
            $w insert end \n
        }
    }

    close $ch1
    close $ch2

    # Mark aligned lines
    if {[info exists ::diff($top,aligns)] && \
            [llength $::diff($top,aligns)] > 0} {
        foreach {align1 align2} $::diff($top,aligns) {
            set i [$::widgets($top,wLine1) search -regexp "\\m$align1\\M" 1.0]
            if {$i != ""} {
                $::widgets($top,wLine1) tag add align \
                        "$i linestart" "$i lineend"
            }
            set i [$::widgets($top,wLine2) search -regexp "\\m$align2\\M" 1.0]
            if {$i != ""} {
                $::widgets($top,wLine2) tag add align \
                        "$i linestart" "$i lineend"
            }
        }
    }

    drawMap $top -1
    foreach item {wLine1 wLine2} {
        set w $::widgets($top,$item)
        $w configure -state disabled
    }
    update idletasks

    eval $::widgets($top,enableAlignCmd)
}

proc disableAlign {top} {
    eval $::widgets($top,disableAlignCmd)
}

# Remove one or all alignment pairs
proc clearAlign {top {leftline {}}} {
    if {$leftline == ""} {
        set ::diff($top,aligns) {}
    } else {
        set i 0
        while 1 {
            set i [lsearch -integer -start $i $::diff($top,aligns) $leftline]
            if {$i < 0} break
            if {($i % 2) == 0} {
                set ::diff($top,aligns) [lreplace $::diff($top,aligns) \
                        $i [expr {$i + 1}]]
                break
            } 
            incr i
        }
    }

    if {[llength $::diff($top,aligns)] == 0} {
        disableAlign $top
    }
}

# Mark a line as aligned.
proc markAlign {top n line text} {
    set ::diff($top,align$n) $line
    set ::diff($top,aligntext$n) $text

    set data [$w get $row.0 $row.end]
    if {![regexp {\d+} $data line]} {
        return 1
    }
    set text [$::widgets($top,wDiff$n) get $row.0 $row.end]

    set other [expr {$n == 1 ? 2 : 1}]
    set cmd [list markAlign $top $n $line $text]
    if {![info exists ::diff($top,align$other)]} {
        set label "Mark line for alignment"
    } else {
        set label "Align with line $::diff($top,align$other) on other side"
    }

    if {[info exists ::diff($top,aligns)]} {
        foreach {align1 align2} $::diff($top,aligns) {
            if {$n == 1 && $line == $align1} {
                set label "Remove alignment with line $align2"
                set cmd [list clearAlign $top $align1]
            } elseif {$n == 2 && $line == $align2} {
                set label "Remove alignment with line $align1"
                set cmd [list clearAlign $top $align1]
            }
        }
    }

    .lpm add command -label $label -command $cmd

    return 0
}

###################
# Diff highlighting
###################

    set ::diff($top,nopopup) 1
    tk_popup .lpm $X $Y
    after idle [list after 1 [list set ::diff($top,nopopup) 0]]

    return
}

# This is called when right clicking over the line numbers which are not
# marked for changes
proc rowPopup {w X Y x y} {
    set top [winfo toplevel $w]
    if {[info exists ::diff($top,nopopup)] && $::diff($top,nopopup)} return
    destroy .lpm
    menu .lpm

    regexp {(\d+)\D*$} $w -> n

    label $top.ls -width 1 -pady 0 -padx 0 \
            -textvariable ::widgets($top,isearchLabel)
    addBalloon $top.ls "Incremental search indicator"
    canvas $top.c -width 6 -bd 0 -selectborderwidth 0 -highlightthickness 0


    applyColor
    foreach w [list $top.ft1.tt $top.ft2.tt] {
        $w tag configure last -underline 1

        $w tag raise sel
        bind $w <ButtonPress-3> "zoomRow %W %X %Y %x %y"
        bind $w <ButtonRelease-3> "unzoomRow %W"
    }
    foreach w [list $top.ft1.tl $top.ft2.tl] {
        $w tag configure align -underline 1
        bind $w <ButtonPress-3> "rowPopup %W %X %Y %x %y"
    }

    grid $top.l1   $top.le -        $top.l2   -row 1 -sticky news
    grid $top.ft1  $top.c  $top.sby $top.ft2  -row 2 -sticky news
    grid $top.sbx1 $top.ls -        $top.sbx2 -row 3 -sticky news
    grid columnconfigure $top {0 3} -weight 1

    set ch [open $file r]
    set data [read $ch]
    close $ch

    set tags {}
    while {$data != ""} {
        if {[regexp {^([^<]*)<(/?)([^>]+)>(.*)$} $data -> pre sl tag post]} {
            $w insert end [subst -nocommands -novariables $pre] $tags
            set i [lsearch $tags $tag]
            if {$sl != ""} {
                # Remove tag
                if {$i >= 0} {
                    set tags [lreplace $tags $i $i]
                }
            } else {
                # Add tag
                lappend tags $tag
            }
            set data $post
        } else {
            $w insert end [subst -nocommands -novariables $data] $tags
            set data ""
        }
    }
}

proc makeHelpWin {} {
    global Pref

    set relief [$w.t cget -relief]
    $w configure -relief $relief -borderwidth $bw
    $w.t configure -borderwidth 0

    # Set up tags
    $w.t tag configure ul -underline 1
    $w.t tag configure b -font tutFontB
    $w.t tag configure bullet -tabs "1c" -lmargin2 "1c"

    insertTaggedText $w.t $doc
    $w.t configure -state disabled
}

proc printUsage {} {
    puts {Usage: eskil.tcl [options] [file1] [file2]