.TH \%nroff 1 "2026-03-15" "groff 1.24.1"
.SH Name
\%nroff \- format documents with
.I groff
for terminal (\[lq]TTY\[rq]) devices
.
.
.\" ====================================================================
.\" Legal Terms
.\" ====================================================================
.\"
.\" Copyright 1989-2023 Free Software Foundation, Inc.
.\"           2018-2024 G. Branden Robinson
.\"
.\" Permission is granted to make and distribute verbatim copies of this
.\" manual provided the copyright notice and this permission notice are
.\" preserved on all copies.
.\"
.\" Permission is granted to copy and distribute modified versions of
.\" this manual under the conditions for verbatim copying, provided that
.\" the entire resulting derived work is distributed under the terms of
.\" a permission notice identical to this one.
.\"
.\" Permission is granted to copy and distribute translations of this
.\" manual into another language, under the above conditions for
.\" modified versions, except that this permission notice may be
.\" included in translations approved by the Free Software Foundation
.\" instead of in the original English.
.
.
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.\" ====================================================================
.SH Synopsis
.\" ====================================================================
.
.SY \%nroff
.RB [ \-abcCEhikpRStUVzZ ]
.RB [ \-d\~\c
.IR ctext ]
.RB [ \-d\~\c
.IB string =\c
.IR text ]
.RB [ \-D\~\c
.IR fallback-input-encoding ]
.RB [ \-I\~\c
.IR inclusion-directory ]
.RB [ \-K\~\c
.IR input-encoding ]
.RB [ \-m\~\c
.IR macro-package ]
.RB [ \-M\~\c
.IR macro-directory ]
.RB [ \-n\~\c
.IR page-number ]
.RB [ \-o\~\c
.IR page-list ]
.RB [ \-P\~\c
.IR postprocessor-argument ]
.RB [ \-r\~\c
.IR cnumeric-expression ]
.RB [ \-r\~\c
.IB register =\c
.IR numeric-expression ]
.RB [ \-T\~\c
.IR output-device ]
.RB [ \-w\~\c
.IR warning-category ]
.RB [ \-W\~\c
.IR warning-category ]
.RI [ file\~ .\|.\|.]
.YS
.
.
.P
.SY \%nroff
.B \-\-help
.YS
.
.
.P
.SY \%nroff
.B \-v
.RI [ other-nroff-option \~.\|.\|.]
.YS
.
.SY \%nroff
.B \%\-\-version
.RI [ other-nroff-option \~.\|.\|.]
.YS
.
.
.\" ====================================================================
.SH Description
.\" ====================================================================
.
.I \%nroff
formats documents written in the
.MR groff 7
language for typewriter-like devices such as terminal emulators.
.
GNU
.I nroff \" GNU
emulates the AT&T
.I nroff \" AT&T
command using
.MR groff 1 .
.
.I \%nroff
generates output via
.MR grotty 1 ,
.IR groff 's
terminal output driver,
which needs to know the character encoding scheme used by the device.
.
Consequently,
acceptable arguments to the
.B \-T
option are
.BR ascii ,
.BR latin1 ,
and
.BR utf8 ;
any others are ignored.
.
If neither the
.I \%GROFF_TYPESETTER
environment variable nor the
.B \-T
command-line option
(which overrides the environment variable)
specifies a (valid) device,
.I \%nroff
consults the locale to select an appropriate output device.
.
It first tries the
.MR locale 1
program,
then checks several locale-related environment variables;
see section \[lq]Environment\[rq] below.
.
If all of the foregoing fail,
.I \%nroff
assumes
.RB \[lq] "\-T ascii" \[rq].
.
.
.P
The
.BR \-a ,
.BR \-b ,
.BR \-c ,
.BR \-C ,
.BR \-d ,
.BR \-E ,
.BR \-i ,
.BR \-I ,
.BR \-m ,
.BR \-M ,
.BR \-n ,
.BR \-o ,
.BR \-r ,
.BR \-U ,
.BR \-w ,
.BR \-W ,
and
.B \-z
options have the effects described in
.MR \%troff 1 .
.
.B \-c
and
.B \-h
imply
.RB \[lq] "\-P \-c" \[rq]
and
.RB \[lq] "\-P \-h" \[rq],
respectively;
.B \-c
is also meaningful to
.I \%troff
itself.
.
Further,
GNU
.I nroff \" GNU
ignores the AT&T
.I nroff \" AT&T
options
.BR \-e ,
.BR \-q ,
and
.BR \-s .
.
.MR groff 1
documents options
.BR \-D ,
.BR \-k ,
.BR \-K ,
.BR \-p ,
.BR \-P ,
.BR \-R ,
.BR \-t ,
.BR \-S ,
and
.BR \-Z .
.
.B \-V
causes
.I \%nroff
to display the constructed
.I groff
command on the standard output stream,
but does not execute it.
.
.B \-v
and
.B \%\-\-version
show version information about
.I \%nroff
and the programs it runs,
while
.B \-\-help
displays a usage message;
all exit afterward.
.
.
.\" ====================================================================
.SH "Exit status"
.\" ====================================================================
.
.I \%nroff
exits with
.RB status\~ 2
if there was a problem parsing its arguments,
with
.RB status\~ 0
if any of the options
.BR \-V ,
.BR \-v ,
.BR \%\-\-version ,
or
.B \-\-help
were specified,
and with the status of
.I groff
otherwise.
.
.
.\" ====================================================================
.SH Environment
.\" ====================================================================
.
Normally,
the path separator in environment variables ending with
.I PATH
is the colon;
this may vary depending on the operating system.
.
For example,
Windows uses a semicolon instead.
.
.
.TP
.I GROFF_BIN_PATH
Locate
.I groff \" system
commands
in these directories,
followed by those in
.IR PATH .
.
If not set,
the installation directory of GNU
.I roff
executables,
.IR /usr/\:\%bin ,
is searched before
.IR PATH .
.
.
.TP
.I GROFF_TYPESETTER
specifies the default output device for
.IR groff .
.
.
.TP
.I LC_ALL
.TQ
.I LC_CTYPE
.TQ
.I LANG
.TQ
.I LESSCHARSET
are pattern-matched in this order for contents matching standard
character encodings supported by
.I groff
in the event no
.B \-T
option is given and
.I \%GROFF_TYPESETTER
is unset,
or the values specified are invalid.
.
.
.\" ====================================================================
.SH Files
.\" ====================================================================
.
.TP
.I /usr/\:\%share/\:\%groff/\:\%1.24.1/\:\%tmac/\:\%tty\-char\:.tmac
defines fallback definitions of
.I roff
special characters.
.
These definitions more poorly optically approximate typeset output
than those of
.I tty.tmac
in favor of communicating semantic information.
.
.I nroff
loads it automatically.
.
.
.\" ====================================================================
.SH Notes
.\" ====================================================================
.
Pager programs like
.MR more 1
and
.MR less 1
may require command-line options to correctly handle some output
sequences;
see
.MR grotty 1 .
.
.
.\" ====================================================================
.SH "See also"
.\" ====================================================================
.
.MR groff 1 ,
.MR \%troff 1 ,
.MR grotty 1 ,
.MR locale 1 ,
.MR roff 7
.
.
.\" Restore compatibility mode (for, e.g., Solaris 10/11).
.cp \n[*groff_nroff_1_man_C]
.do rr *groff_nroff_1_man_C
.
.
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