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Using dedicated input tools for shell GUI interfacing
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Yes/NO input

  "whiptail" (ncurses)
  "dialog"  (ncurses)
  "gdialog" (gtk)
  "kdialog" (kde)

Example:
  if whiptail --yesno "Is this a good question" 20 60  # ncurses
  then echo Yes 
  else echo No
  fi

Or
  dialog  --yesno "Is this a good question" 20 60    # ncurses
  gdialog --yesno "Is this a good question" 20 60    # gtk
  kdialog --yesno "Is this a good question" 20 60    # kde

  Xdialog --yesno "Is this a good question" 20 60    # xwindows?

You can get the Yes/No test for your locale using...

locale LC_MESSAGES

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Terminal progress bar example...

  dialog --gauge "Filling the tank" 20 60 0 < <(
    for i in {1..100};do
      printf "XXX\n%d\n%(%a %b %T)T progress: %d\nXXX\n" $i -1 $i
      sleep .033
    done
  )

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