Provided by: groff-base_1.22.3-7_amd64 bug


       grog — guess options for a following groff command


       grog [-C] [--run] [--warnings] [--ligatures] [ groff-option ....]  [--] [ filespec ....]
       grog -h | --help
       grog -v | --version


       grog  reads  the  input  (file  names or standard input) and guesses which of the groff(1)
       options are needed to perform the input with the groff program.

              The corresponding groff command is usually displayed in standard output.  With  the
              option  --run,  the  generated line is output into standard error and the generated
              groff command is run on the standard output.


       The option -v or --version prints information on the version number.  Also  -h  or  --help
       prints  usage  information.   Both  of  these  options automatically end the grog program.
       Other options are thenignored, and no groff command line is generated.   The  following  3
       options are the only grog options,

       -C     this  option  means enabling the groff compatibility mode, which is also transfered
              to the generated groff command line.

              this option forces to include the arguments -P-y -PU  within  the  generated  groff
              command line.

       --run  with  this option, the command line is output at standard error and then run on the

              with this option, some more warnings are output to standard error.

       All other specified short  options  (words  starting  with  one  minus  character  -)  are
       interpreted  as  groff  options  or option clusters with or without argument.  No space is
       allowed between options and their argument.  Except from the -marg  options,  all  options
       will  be passed on, i.e. they are included unchanged in the command for the output without
       effecting the work of grog.

       A filespec argument can either be the name of an existing file or a single minus - to mean
       standard input.  If no filespec is specified standard input is read automatically.


       grog  reads  all filespec parameters as a whole.  It tries to guess which of the following
       groff options are required for running the input under groff: -e, -g, -G, -j, -J, -p,  -R,
       -s, -t.  -man, -mdoc, -mdoc-old, -me, -mm, -mom, and -ms.

       The guessed groff command including those options and the found filespec parameters is put
       on the standard output.

       It is possible to specify arbitrary groff options on the command line.  These  are  passed
       on the output without change, except for the -marg options.

       The  groff program has trouble when the wrong -marg option or several of these options are
       specified.  In these cases, grog will print an error message and exit with an error  code.
       It  is  better  to  specify  no -marg option.  Because such an option is only accepted and
       passed when grog does not find any of these options or the same option is found.

       If several different -marg options are found by grog an error message is produced and  the
       program  is  terminated  with  an  error  code.   But the output is written with the wrong
       options nevertheless.

       Remember that it is not necessary to determine a macro package.  A roff file can  also  be
       written  in  the  groff  language  without any macro package.  grog will produce an output
       without an -marg option.

       As groff also works with pure text files without any roff requests, grog cannot be used to
       identify a file to be a roff file.

       The groffer(1) program heavily depends on a working grog.

       The  grog source contains two files written in different programming languages: is
       the Perl version, while is a  shell  script  using  awk(1).   During  the  run  of
       make(1),  it  is determined whether the system contains a suitable version of perl(1).  If
       so, is transformed into grog; otherwise is used instead.


       * Calling


         results in

                groff -me

         So grog recognized that the file is written with the -me macro package.

       * On the other hand,



                groff -p -t -e -ms

         Besides determining the  macro  package  -ms,  grog  recognized  that  the  file
         additionally needs -pte, the combination of -p for pic, -t for tbl, and -e for eqn.

       * If both of the former example files are combined by the command


         an  error message is sent to standard error because groff cannot work with two different
         macro packages:

                grog: error: there are several macro packages: -me -ms

         Additionally the corresponding output with the wrong  options  is  printed  to  standard

                groff -pte -me -ms

         But the program is terminated with an error code.

       * The call of

                grog -ksS -Tdvi grnexmpl.g

         contains  several groff options that are just passed on the output without any interface
         to grog.  These are the option cluster -ksS consisting of -k, -s, and -S; and the option
         -T with argument dvi.  The output is

                groff -k -s -S -Tdvi grnexmpl.g

         so  no  additional  option was added by grog.  As no option -marg was found by grog this
         file does not use a macro package.


       groff(1), groffer(1) troff(1), tbl(1), pic(1), chem(1), eqn(1), refer(1), grn(1), grap(1),
              Man-pages of section 1 can be viewed with either
                     $ man name
              for text mode or
                     $ groffer name
              for graphical mode (default is PDF mode).

       groff_me(7), groff_ms(7), groff_mm(7), groff_mom(7), groff_man(7)
              Man-pages of section 7 can be viewed with either with
                     $ man 7 name
              for text mode or
                     $ groffer 7 name
              for graphical mode (default is PDF mode).


       Copyright © 1989-2014 Free Software Foundation, Inc.

       This file is part of grog, which is part of groff, a free software project.  You can
       redistribute it and/or modify it under the terms of the GNU General Public License version
       2 (GPL2) as published by the Free Software Foundation.

       groff is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
       even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

       The text for GPL2 is available in the internet at GNU copyleft site ⟨


       Written by James Clark.

       Maintained by Werner Lemberg ⟨⟩.

       Rewritten and put under GPL by Bernd Warken ⟨⟩.