Provided by: groff-base_1.22.4-3_amd64 bug

NAME

       grog - guess options for a following groff command

SYNOPSIS

       grog [-C] [-T device] [--run] [--warnings] [--ligatures] [groff-option ...] [--] [filespec
            ...]

       grog -h
       grog --help

       grog -v
       grog --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.  A suitable device is now
       always written as -Tdevice including the groff default as -T ps.

       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.  groffer(1) relies on a perfectly running groff(1).

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, -p, -R,  -s,
       -t (preprocessors); and -man, -mdoc, -mdoc-old, -me, -mm, -mom, and -ms (macro packages).

       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.

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.

AUTHORS

       grog  was  originally written by James Clark.  The current Perl implementation was written
       by Bernd Warken ⟨groff-bernd.warken-72@web.de⟩ with contributions from Ralph Corderoy, and
       is maintained by Werner Lemberg ⟨wl@gnu.org⟩.

SEE ALSO

       groff(1), groffer(1)