Create a top-level window, make some frames, insert a label and an entry form
% global result ; global rtext
% set f [toplevel .prompt -bd 10]
% label $f.msg -text “Please enter a name”
% entry $f.entry -textvariable rtext
% set b [frame $f.buttons -bd 10]
% pack $f.msg $f.entry $f.buttons -side top -fill x