term% ls -F
term% cat index.txt
DEROFF(1)                   General Commands Manual                  DEROFF(1)

       deroff - remove nroff, troff, tbl and eqn constructs

       deroff [ -w ] file ...

       Deroff reads each file in sequence and removes all nroff and troff com‐
       mand lines, backslash constructions, macro definitions, eqn  constructs
       (between  `.EQ'  and  `.EN' lines or between delimiters), and table de‐
       scriptions and writes the remainder on  the  standard  output.   Deroff
       follows  chains of included files (`.so' and `.nx' commands); if a file
       has already been included, a `.so' is ignored and  a  `.nx'  terminates
       execution.   If  no input file is given, deroff reads from the standard
       input file.

       If the -w flag is given, the output is a word list, one `word'  (string
       of  letters, digits, and apostrophes, beginning with a letter; apostro‐
       phes are removed) per line, and all other characters  ignored.   Other‐
       wise,  the  output  follows  the original, with the deletions mentioned

       troff(1), eqn(1), tbl(1)

       Deroff is not a complete troff interpreter, so it can  be  confused  by
       subtle constructs.  Most errors result in too much rather than too lit‐
       tle output.