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*                             ENTAB                                  *
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*                  COPYRIGHT 1983 EUGENE H. MALLORY                  *
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PROGRAM:
    ENTAB - Convert runs of spaces to tabs.
USAGE:
    ENTAB [<fid] [>fid]
FUNCTION:
    This copies input to output, replacing strings of spaces by 
    tabs so that the result is visualy the same as the input.
    Tab stops are assumed to occur every 8 characters.
EXAMPLE:
    ENTAB <BIGFILE >LTLFILE
BUGS:
    ENTAB is naive about vertical motion non-printing characters.  
    ENTAB will convert a single blank to a tab if it occurs at 
    a tab stop.  Thus it is not the exact inverse of DETAB.
    





                    _____________________________    
 Standard Input     |                           |   Standard Output
     TEXT           |                           |   TEXT WITH TABS
------------------->|          ENTAB            |----------------------->
                    |                           |
                    |                           |
                    |___________________________|