; OPTELL
;---------------------------------------------------------------
;! The operation to be passed to a task by TELL
;# ADVERB UTILITY GENERAL INTERACTIVE
;-----------------------------------------------------------------------
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;-----------------------------------------------------------------------
;---------------------------------------------------------------
OPTELL    LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
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OPTELL
Type: Adverb (String*4)
Use:  To specify the operation to be used by the TELL verb.
         'ABOR'  Die now, reset file statuses and delete outputs
         'QUIT'  Die now, but save the current output results
         'CHAN'  Change the running parameters
Null Value: None

Verbs:
  TELL......Send parameters to tasks that know to read them on the fly.

Tasks which support this capability:
  APCLN.....Deconvolves images with B. G. Clark CLEAN method.
            Can change DOTV, NITER, beam, and other parameters.
  IMAGR.....Wide-field and/or wide-frequency Cleaning / imaging.
            Can change quite a few parameters
  SCMAP.....Imaging plus self-calibration loop with editing
            Can change several imaging and self-cal parameters.
  SCIMG.....Full-featured imaging plus self-calibration loop with
            editing.  Can change imaging, editing, and self-cal
            parameters.
  SDCLN.....Deconvolves images with CLEAN followed by SDI
            methods.  Can change DOTV, NITER, beam, and other
            parameters.
  UTESS.....Deconvolves multiple images with maximum entropy
            methods - for images of polarization.  Can change
            DOTV, NITER, other parameters.
  VTESS.....Deconvolves multiple images with maximum entropy
            methods.  Can change DOTV, NITER, other parameters.
Tasks which support QUIT or ABOR operations only:
  MCUBE.....Builds n+1 (or n) dimensional images from sets of
            n-dimensional images.
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