GROG(1) 						      General Commands Manual							   GROG(1)

NAME

       grog - guess options for groff command

SYNOPSIS

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

DESCRIPTION

       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 output.

OPTIONS

       The only grog options recognized are -C (which is also passed on) to enable compatibility mode; -v and --version print information  on  the
       version	number;  and  -h  and  --help print usage information.	-v, --version, -h, and --help stop the program directly without printing a
       groff command to standard output.

       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.

DETAILS

       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, -man, -me, -mm, -mom, -ms, -mdoc, -mdoc-old, -p, -R, -g, -G, -s, and  -t.   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: grog.pl is the Perl version, while grog.sh is a shell script
       using  BR  awk (1).  During the run of make(1), it is determined whether the system contains a suitable version of perl(1).  If so, grog.pl
       is transformed into grog; otherwise grog.sh is used instead.

EXAMPLES

       o      Calling

		     grog meintro.me

	      results in

		     groff -me meintro.me

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

       o      On the other hand,

		     grog pic.ms

	      outputs

		     groff -pte -ms pic.ms

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

       o      If both files are combined by the command

		     grog meintro.me pic.ms

	      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 output:

		     groff -pte -me -ms meintro.me pic.ms

	      But the program is terminated with an error code.

       o      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 -ksS -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.

       o      grog can also handle files using the chem language.  The example

		     grog chAh_brackets.chem

	      outputs

		     chem chAh_brackets.chem | groff -pe

	      So chem is run first and groff is appended.  The option -p for pic is implied automatically by chem.  Additionally,  the	file  uses
	      eqn with -e.

SEE ALSO

       groff(1),  troff(1),  tbl(1),  pic(1),  eqn(1),	refer(1), grn(1), grap(1), soelim(1), groff_me(7), groff_ms(7), groff_mm(7), groff_mom(7),
       groff_man(7), groffer(1)

COPYING

       Copyright (C) 1989-2000, 2001, 2002, 2003, 2006, 2007, 2009, 2010 Free Software Foundation, Inc.  Written by James  Clark.   Maintained	by
       Werner Lemberg <wl@gnu.org>.  Rewritten and put under GPL by Bernd Warken.

       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 (GPL) as published by the Free Software Foundation, either version 2, or (at your option) any later version.

       You should have received a copy of the GNU General Public License along with groff, see the files COPYING and LICENSE in the top  directory
       of  the	groff  source  package.   Or read the man page gpl(1).	You can also write to the Free Software Foundation, 51 Franklin St - Fifth
       Floor, Boston, MA 02110-1301, USA.

Groff Version 1.21						 31 December 2010							   GROG(1)