grn is a preprocessor for including
gremlin pictures in
groff input.
grn writes to standard output, processing only input lines between two that start with
.GS and
.GE. Those lines must contain
grn commands (see below). These commands request a
gremlin file, and the picture in that file is converted and placed in the
troff input stream. The
.GS request may be followed by a C, L, or R to center, left, or right justify the whole
gremlin picture (default justification is center). If no
file is mentioned, the standard input is read. At the end of the picture, the position on the page is the bottom of the
gremlin picture. If the
grn entry is ended with
.GF instead of
.GE, the position is left at the top of the picture.
Please note that currently only the -me macro package has support for .GS, .GE, and .GF.
The following command-line options are understood:
-Tdev
Prepare output for printer dev. The default device is ps. See groff(1) for acceptable devices.
-Mdir
Prepend dir to the default search path for gremlin files. The default path is (in that order) the current directory, the home directory, /usr/share/tmac, /usr/share/tmac, and /usr/share/tmac.
-Fdir
Search dir for subdirectories devname (name is the name of the device) for the DESC file before the default font directories /usr/share/groff_font, /usr/share/groff_font, and /usr/share/groff_font.
-C
Recognize .GS and .GE (and .GF) even when followed by a character other than space or newline.
-v
Print the version number.