#!/usr/local/bin/wish -f

frame .topbuttons -borderwidth 10
pack .topbuttons -side top -fill both

# Three buttons and an entry field

button .topbuttons.quit -text Quit -command exit
button .topbuttons.cat   -text Cat -command Cat
entry  .topbuttons.e1 -width 40 -relief sunken
pack .topbuttons.quit -side right
pack .topbuttons.cat -side right
pack .topbuttons.e1 -fill x -expand yes

# Text area with a scrollbar

text .log -xscrollcommand ".xscroll set" -yscrollcommand ".yscroll set" \
     -width 50 -height 20 -bd 2 -relief raised  -wrap none
scrollbar .yscroll -command ".log yview"
scrollbar .xscroll -command ".log xview" -orient horiz

pack .yscroll -side right -fill y
pack .xscroll -side bottom -fill x
pack .log -side top -expand yes -fill both

# The cat procedure.  The delete line says to delete all characters in 
# .log from line 1, char 0 to the end.

proc Cat {} {
     set filename [.topbuttons.e1 get]
     catch {exec cat $filename} results
     .log delete 1.0 end
     .log insert end $results
}