Provided by: groff-base_1.22.3-10_amd64 
NAME
grog — guess options for a following groff command
SYNOPSIS
grog [-C] [--run] [--warnings] [--ligatures] [ 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 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.
OPTIONS
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.
--ligatures
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 computer.
--warnings
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.
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, -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: grog.pl is the Perl
version, while grog.sh 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, grog.pl is transformed into grog;
otherwise grog.sh is used instead.
EXAMPLES
* 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.
* On the other hand,
grog pic.ms
outputs
groff -p -t -e -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.
* If both of the former example 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.
* 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.
SEE ALSO
groff(1), groffer(1) troff(1), tbl(1), pic(1), chem(1), eqn(1), refer(1), grn(1), grap(1), soelim(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).
COPYING
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 ⟨http://www.gnu.org/licenses/
gpl-2.0.txt⟩.
AUTHORS
Written by James Clark.
Maintained by Werner Lemberg ⟨wl@gnu.org⟩.
Rewritten and put under GPL by Bernd Warken ⟨groff-bernd.warken-72@web.de⟩.