There are also several environment variables (of the operating system,
gtroff) that can modify the behavior of
This search path, followed by
PATH, is used for commands executed
If this is set to X, then
Xtroff instead of
gtroff. This also applies to
soelim. It does not apply to
The default command prefix is determined during the installation process. If a non-GNU troff system is found, prefix ‘g’ is used, none otherwise.
The value of this environment value is passed to the
preprocessor to select the encoding of input files. Setting this option
groff’s command-line option -k (that is,
groff actually always calls
preconv). If set without a
preconv without arguments. An explicit
-K command-line option overrides the value of
GROFF_ENCODING. See the manual page of
preconv for details.
A colon-separated list of directories in which to search for the
devname directory (before the default directories are
tried). See Font Directories.
A colon-separated list of directories in which to search for macro files (before the default directories are tried). See Macro Directories.
The directory in which
groff creates temporary files. If this is
not set and
TMPDIR is set, temporary files are created in that
directory. Otherwise temporary files are created in a system-dependent
default directory (on Unix and GNU/Linux systems, this is usually
post-grohtml can create temporary files in this directory.
The default output device.
A timestamp (expressed as seconds since the Unix epoch) to use in place of
the current time when initializing time-based built-in registers such as
Note that MS-DOS and MS-Windows ports of
groff use semi-colons,
rather than colons, to separate the directories in the lists described