.\" $OpenBSD: spell.1,v 1.13 2016/12/28 22:47:11 schwarze Exp $
.\"
.\" Copyright (C) 1985, 1993, 1994
.\"	The Regents of the University of California.  All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\" Copyright (C) Caldera International Inc.  2001-2002.
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code and documentation must retain the above
.\"    copyright notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. All advertising materials mentioning features or use of this software
.\"    must display the following acknowledgement:
.\"	This product includes software developed or owned by Caldera
.\"	International, Inc.
.\" 4. Neither the name of Caldera International, Inc. nor the names of other
.\"    contributors may be used to endorse or promote products derived from
.\"    this software without specific prior written permission.
.\"
.\" USE OF THE SOFTWARE PROVIDED FOR UNDER THIS LICENSE BY CALDERA
.\" INTERNATIONAL, INC. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR
.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
.\" IN NO EVENT SHALL CALDERA INTERNATIONAL, INC. BE LIABLE FOR ANY DIRECT,
.\" INDIRECT INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
.\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
.\" STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
.\" IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
.\" POSSIBILITY OF SUCH DAMAGE.
.\"
.\"	@(#)spell.1	8.2 (Berkeley) 4/18/94
.\"
.Dd $Mdocdate: December 28 2016 $
.Dt SPELL 1
.Os
.Sh NAME
.Nm spell
.Nd find spelling errors
.Sh SYNOPSIS
.Nm spell
.Op Fl biltvx
.Op Fl d Ar list
.Op Fl h Ar spellhist
.Oo
.Fl m
.Ar a | e | l | m | s
.Oc
.Op Fl s Ar list
.Op + Ns Ar extra_list
.Op Ar
.Sh DESCRIPTION
.Nm spell
collects words from the named documents and looks them up in a spelling list.
Words that neither occur among nor are derivable (by applying certain
inflections, prefixes or suffixes) from words in the spelling list
are printed on the standard output.
.Pp
If no files are named, words are collected from the standard input.
.Nm
ignores most troff, tbl, eqn, and pic constructions.
Copies of all output may be accumulated in the history file,
if one is specified.
.Pp
By default,
.Nm
(like
.Xr deroff 1 )
follows chains of included files
.Po
.Dq .so
and
.Dq .nx
commands
.Pc .
.Pp
The default spelling list is based on Webster's Second International
dictionary and should be fairly complete.
Words that appear in the
.Dq stop list
are immediately flagged as misspellings, regardless of whether or not
they exist in one of the word lists.
This helps filter out misspellings (e.g. thier=thy\-y+ier)
that would otherwise pass.
Additionally, the
.Pa british
file is also used as a stop list unless the
.Fl b
option is specified.
.Pp
Site administrators may add words to the local word list,
.Pa /usr/local/share/dict/words
or the local stop list,
.Pa /usr/local/share/dict/stop .
.Pp
All word (and stop) lists must be sorted in lexicographical order
with case folded.
The simplest way to achieve this is to use
.Dq sort -df .
If the word files are incorrectly sorted,
.Nm
will not be able to operate correctly.
.Pp
The options are as follows:
.Bl -tag -width Ds
.It Fl b
Check British spelling.
Besides preferring
.Em centre , colour , speciality , travelled ,
etc., this option insists upon
.Fl ise
in words like
.Em standardise ,
Fowler and the OED to the contrary notwithstanding.
In this mode, American variants of words are added to the stop list.
.It Fl d Ar list
Use the specified word list instead of the default system word list.
The word list must be sorted as specified above.
.It Fl h Ar spellhist
Store misspelled words in the specified history file.
The output of
.Li who -m
is appended to the history file after the list of misspelled words.
.It Fl i
Instruct
.Xr deroff 1
to ignore
.Dq .so
and
.Dq .nx
commands.
.It Fl l
Use
.Sy delatex
instead of
.Xr deroff 1
if it is present on the system.
.It Fl m
Enable support for common
troff macro packages; this option is passed verbatim to
.Xr deroff 1 .
Refer to the
.Fl m
description in
.Xr deroff 1
for details.
.It Fl s Ar list
Use the specified stop list instead of the default system stop list.
The stop list must be sorted as specified above.
.It Fl t
Use
.Sy detex
instead of
.Xr deroff 1
if it is present on the system.
.It Fl v
Print all words not literally in the spelling list in addition to
plausible derivations from spelling list words.
.It Fl x
Print every plausible stem, prefixed with
.Sq = .
.It + Ns Ar extra_list
Use
.Ar extra_list
in addition to the default word list.
The extra word list must be sorted as specified above.
.El
.Sh FILES
.Bl -tag -width /usr/local/share/dict/wordsxx -compact
.It Pa /usr/share/dict/words
Default spelling list.
.It Pa /usr/share/dict/american
American spelling of certain words.
.It Pa /usr/share/dict/british
British spelling of certain words.
.It Pa /usr/share/dict/stop
Default stop list.
.It Pa /usr/local/share/dict/words
Local spelling list (optional).
.It Pa /usr/local/share/dict/stop
Local stop list (optional).
.It Pa /usr/libexec/spellprog
Binary executed by the shell script
.Pa /usr/bin/spell .
.El
.Sh SEE ALSO
.Xr deroff 1 ,
.Xr look 1 ,
.Xr sed 1 ,
.Xr sort 1 ,
.Xr tee 1
.Sh HISTORY
The
.Nm spell
command appeared in
.At v6 .
.Pp
Unlike historic versions, the
.Ox
.Nm
command does not use hashed word files.
Instead, it uses lexicographically sorted files and the same technique as
.Xr look 1 .
.Sh BUGS
The spelling list lacks many technical terms; new installations will
probably wish to monitor the output for several months to gather local
additions.
.Pp
British spelling was done by an American.
.Pp
In
.Fl x
mode it would be nicer if the stems were grouped with the appropriate word.