grog - guess options for a following groff command
grog [ -C ] [ -T
device ] [ --run ] [ --warnings ] [
--ligatures ] [groff-option
. . .] [
-- ] [filespec
. . .] grog
-h grog --help
grog -v grog
--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. 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).
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,
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.
with this option, the command line is output at standard error and then run on the computer.
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, -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.
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.
grog was originally written by James Clark. The current Perl implementation was written by mailto:groff-bernd.warken-72@web.de">Bernd Warken with contributions from Ralph Corderoy, and is maintained by mailto:wl@gnu.org">Werner Lemberg.