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Lots of minor rewording and grammar correction.

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From Brian Youmans.
This commit is contained in:
Jim Meyering 2000-06-24 11:53:51 +00:00
parent 4604a7892b
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doc/textutils.texi
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@ -317,19 +317,19 @@ Equivalent to @samp{-vET}.
@opindex -B
@opindex --binary
@cindex binary and text I/O in cat
On MS-DOS and MS-Windows only, read and write the
files in binary mode. By default, @code{cat} on MS-DOS/MS-Windows uses
binary mode only when standard output is redirected to a file or a pipe;
this option overrides that. Binary file I/O is used so that the files
retain their format (Unix text as opposed to DOS text and binary),
because @code{cat} is frequently used as a file-copying program. Some
options (see below) cause @code{cat} read and write files in text mode
because then the original file contents aren't important (e.g., when
lines are numbered by @code{cat}, or when line endings should be
marked). This is so these options work as DOS/Windows users would
expect; for example, DOS-style text files have their lines end with
the CR-LF pair of characters which won't be processed as an empty line
by @samp{-b} unless the file is read in text mode.
On MS-DOS and MS-Windows only, read and write the files in binary mode.
By default, @code{cat} on MS-DOS/MS-Windows uses binary mode only when
standard output is redirected to a file or a pipe; this option overrides
that. Binary file I/O is used so that the files retain their format
(Unix text as opposed to DOS text and binary), because @code{cat} is
frequently used as a file-copying program. Some options (see below)
cause @code{cat} to read and write files in text mode because in those
cases the original file contents aren't important (e.g., when lines are
numbered by @code{cat}, or when line endings should be marked). This is
so these options work as DOS/Windows users would expect; for example,
DOS-style text files have their lines end with the CR-LF pair of
characters, which won't be processed as an empty line by @samp{-b} unless
the file is read in text mode.
@item -b
@itemx --number-nonblank
@ -813,12 +813,12 @@ Output as hexadecimal shorts. Equivalent to @samp{-tx2}.
@item -C
@itemx --traditional
@opindex --traditional
Recognize the pre-POSIX non-option arguments that traditional @code{od}
Recognize the pre-@sc{posix} non-option arguments that traditional @code{od}
accepted. The following syntax:
@example
@smallexample
od --traditional [@var{file}] [[+]@var{offset}[.][b] [[+]@var{label}[.][b]]]
@end example
@end smallexample
@noindent
can be used to specify at most one file and optional arguments
@ -983,24 +983,27 @@ is @samp{space}). For multicolumn output, lines will always be truncated to
column output no line truncation occurs by default. Use @samp{-W} option to
truncate lines in that case.
@c FIXME:??? Should this be something like "Starting with version 1.22i,..."
Including version 1.22i:
Some small @var{letter options} (@samp{-s}, @samp{-w}) has been redefined
with the object of a better @var{posix} compliance. The output of some
further cases has been adapted to other @var{unix}es. A violation of
downward compatibility has to be accepted.
@c FIXME: this whole section here sounds very awkward to me. I
@c made a few small changes, but really it all needs to be redone. - Brian
Some small @var{letter options} (@samp{-s}, @samp{-w}) have been redefined
with the object of a better @sc{posix} compliance. The output of some
further cases has been adapted to other Unix systems. These changes are
not compatible with earlier versions of the program.
Some @var{new capital letter} options (@samp{-J}, @samp{-S}, @samp{-W})
has been introduced to turn off unexpected interferences of small letter
have been introduced to turn off unexpected interferences of small letter
options. The @samp{-N} option and the second argument @var{last_page}
of @samp{+FIRST_PAGE} offer more flexibility. The detailed handling of
form feeds set in the input files requires @samp{-T} option.
form feeds set in the input files requires the @samp{-T} option.
Capital letter options dominate small letter ones.
Capital letter options override small letter ones.
Some of the option-arguments (compare @samp{-s}, @samp{-S}, @samp{-e},
@samp{-i}, @samp{-n}) cannot be specified as separate arguments from the
preceding option letter (already stated in the @var{posix} specification).
preceding option letter (already stated in the @sc{posix} specification).
The program accepts the following options. Also see @ref{Common options}.
@ -1110,7 +1113,7 @@ Merge lines of full length. Used together with the column options
@samp{-W/-w} line truncation;
no column alignment used; may be used with @samp{-S[@var{string}]}.
@samp{-J} has been introduced (together with @samp{-W} and @samp{-S})
to disentangle the old (@var{posix} compliant) options @samp{-w} and
to disentangle the old (@sc{posix}-compliant) options @samp{-w} and
@samp{-s} along with the three column options.
@ -1120,7 +1123,7 @@ to disentangle the old (@var{posix} compliant) options @samp{-w} and
@opindex --length
Set the page length to @var{page_length} (default 66) lines, including
the lines of the header [and the footer]. If @var{page_length} is less
than or equal 10 (and <= 3 with @samp{-F}), the header and footer are
than or equal to 10 (or <= 3 with @samp{-F}), the header and footer are
omitted, and all form feeds set in input files are eliminated, as if
the @samp{-T} option had been given.
@ -1129,7 +1132,7 @@ the @samp{-T} option had been given.
@opindex -m
@opindex --merge
Merge and print all @var{file}s in parallel, one in each column. If a
line is too long to fit in a column, it is truncated, unless @samp{-J}
line is too long to fit in a column, it is truncated, unless the @samp{-J}
option is used. @samp{-S[@var{string}]} may be used. Empty pages in
some @var{file}s (form feeds set) produce empty columns, still marked
by @var{string}. The result is a continuous line numbering and column
@ -1146,8 +1149,8 @@ Provide @var{digits} digit line numbering (default for @var{digits} is
5). With multicolumn output the number occupies the first @var{digits}
column positions of each text column or only each line of @samp{-m}
output. With single column output the number precedes each line just as
@samp{-m} does. Default counting of the line numbers starts with 1st
line of the input file (not the 1st line printed, compare the
@samp{-m} does. Default counting of the line numbers starts with the
first line of the input file (not the first line printed, compare the
@samp{--page} option and @samp{-N} option).
Optional argument @var{number-separator} is the character appended to
the line number to separate it from the text followed. The default
@ -1155,8 +1158,8 @@ separator is the TAB character. In a strict sense a TAB is always
printed with single column output only. The @var{TAB}-width varies
with the @var{TAB}-position, e.g. with the left @var{margin} specified
by @samp{-o} option. With multicolumn output priority is given to
@samp{equal width of output columns} (a @var{posix} specification).
The @var{TAB}-width is fixed to the value of the 1st column and does
@samp{equal width of output columns} (a @sc{posix} specification).
The @var{TAB}-width is fixed to the value of the first column and does
not change with different values of left @var{margin}. That means a
fixed number of spaces is always printed in the place of the
@var{number-separator tab}. The tabification depends upon the output
@ -1196,7 +1199,7 @@ is the TAB character without @samp{-w} and @samp{no character} with
@samp{-w}. Without @samp{-s} default separator @samp{space} is set.
@samp{-s[char]} turns off line truncation of all three column options
(@samp{-COLUMN}|@samp{-a -COLUMN}|@samp{-m}) except @samp{-w} is set.
That is a @var{posix} compliant formulation.
That is a @sc{posix}-compliant formulation.
@item -S[@var{string}]
@ -1251,7 +1254,7 @@ output only (default for @var{page_width} is 72). @samp{-s[CHAR]} turns
off the default page width and any line truncation and column alignment.
Lines of full length are merged, regardless of the column options
set. No @var{page_width} setting is possible with single column output.
A @var{posix} compliant formulation.
A @sc{posix}-compliant formulation.
@item -W @var{page_width}
@itemx --page_width=@var{page_width}
@ -1812,8 +1815,8 @@ containing the cumulative counts, with the file name @file{total}. The
counts are printed in this order: newlines, words, bytes.
By default, each count is output right-justified in a 7-byte field with
one space between fields so that the numbers and file names line up nicely
in columns. However, POSIX requires that there be exactly one space
separating columns. You can make @code{wc} use the POSIX-mandated
in columns. However, @sc{posix} requires that there be exactly one space
separating columns. You can make @code{wc} use the @sc{posix}-mandated
output format by setting the @env{POSIXLY_CORRECT} environment variable.
By default, @code{wc} prints all three counts. Options can specify
@ -2388,13 +2391,13 @@ sort -t : -n -k 5b,5 -k 3,3 /etc/passwd
@end example
@item
Generate a tags file in case insensitive sorted order.
Generate a tags file in case-insensitive sorted order.
@example
@smallexample
find src -type f -print0 | sort -t / -z -f | xargs -0 etags --append
@end example
@end smallexample
The use of @samp{-print0}, @samp{-z}, and @samp{-0} in this case mean
The use of @samp{-print0}, @samp{-z}, and @samp{-0} in this case means
that pathnames that contain Line Feed characters will not get broken up
by the sort operation.
@ -2463,7 +2466,7 @@ The program accepts the following options. Also see @ref{Common options}.
@opindex --skip-fields
Skip @var{n} fields on each line before checking for uniqueness. Fields
are sequences of non-space non-tab characters that are separated from
each other by at least one spaces or tabs.
each other by at least one space or tab.
@item +@var{n}
@itemx -s @var{n}
@ -2630,35 +2633,35 @@ ptx -G [@var{option} @dots{}] [@var{input} [@var{output}]]
@end example
The @samp{-G} (or its equivalent: @samp{--traditional}) option disables
all GNU extensions and revert to traditional mode, thus introducing some
limitations, and changes several of the program's default option values.
all GNU extensions and reverts to traditional mode, thus introducing some
limitations and changing several of the program's default option values.
When @samp{-G} is not specified, GNU extensions are always enabled. GNU
extensions to @code{ptx} are documented wherever appropriate in this
document. For the full list, see @xref{Compatibility in ptx}.
Individual options are explained in incoming sections.
Individual options are explained in the following sections.
When GNU extensions are enabled, there may be zero, one or several
@var{file} after the options. If there is no @var{file}, the program
reads the standard input. If there is one or several @var{file}, they
@var{file}s after the options. If there is no @var{file}, the program
reads the standard input. If there is one or several @var{file}s, they
give the name of input files which are all read in turn, as if all the
input files were concatenated. However, there is a full contextual
break between each file and, when automatic referencing is requested,
file names and line numbers refer to individual text input files. In
all cases, the program produces the permuted index onto the standard
all cases, the program outputs the permuted index to the standard
output.
When GNU extensions are @emph{not} enabled, that is, when the program
operates in traditional mode, there may be zero, one or two parameters
besides the options. If there is no parameters, the program reads the
standard input and produces the permuted index onto the standard output.
besides the options. If there are no parameters, the program reads the
standard input and outputs the permuted index to the standard output.
If there is only one parameter, it names the text @var{input} to be read
instead of the standard input. If two parameters are given, they give
respectively the name of the @var{input} file to read and the name of
the @var{output} file to produce. @emph{Be very careful} to note that,
in this case, the contents of file given by the second parameter is
destroyed. This behaviour is dictated only by System V @code{ptx}
compatibility, because GNU Standards discourage output parameters not
destroyed. This behavior is dictated by System V @code{ptx}
compatibility; GNU Standards normally discourage output parameters not
introduced by an option.
Note that for @emph{any} file named as the value of an option or as an
@ -2667,7 +2670,7 @@ standard input is assumed. However, it would not make sense to use this
convention more than once per program invocation.
@menu
* General options in ptx:: Options which affect general program behaviour.
* General options in ptx:: Options which affect general program behavior.
* Charset selection in ptx:: Underlying character set considerations.
* Input processing in ptx:: Input fields, contexts, and keyword selection.
* Output formatting in ptx:: Types of output format, and sizing the fields.
@ -2682,20 +2685,20 @@ convention more than once per program invocation.
@item -C
@itemx --copyright
Prints a short note about the Copyright and copying conditions, then
Print a short note about the copyright and copying conditions, then
exit without further processing.
@item -G
@itemx --traditional
As already explained, this option disables all GNU extensions to
@code{ptx} and switch to traditional mode.
@code{ptx} and switches to traditional mode.
@item --help
Prints a short help on standard output, then exit without further
Print a short help on standard output, then exit without further
processing.
@item --version
Prints the program verison on standard output, then exit without further
Print the program version on standard output, then exit without further
processing.
@end table
@ -2704,16 +2707,17 @@ processing.
@node Charset selection in ptx
@subsection Charset selection
As it is setup now, the program assumes that the input file is coded
@c FIXME: People don't necessarily know what an IBM-PC was these days.
As it is set up now, the program assumes that the input file is coded
using 8-bit ISO 8859-1 code, also known as Latin-1 character set,
@emph{unless} if it is compiled for MS-DOS, in which case it uses the
@emph{unless} it is compiled for MS-DOS, in which case it uses the
character set of the IBM-PC. (GNU @code{ptx} is not known to work on
smaller MS-DOS machines anymore.) Compared to 7-bit @sc{ascii}, the set of
characters which are letters is then different, this fact alters the
behaviour of regular expression matching. Thus, the default regular
expression for a keyword allows foreign or diacriticized letters.
Keyword sorting, however, is still crude; it obeys the underlying
character set ordering quite blindly.
smaller MS-DOS machines anymore.) Compared to 7-bit @sc{ascii}, the set
of characters which are letters is different; this alters the behavior
of regular expression matching. Thus, the default regular expression
for a keyword allows foreign or diacriticized letters. Keyword sorting,
however, is still crude; it obeys the underlying character set ordering
quite blindly.
@table @samp
@ -2735,7 +2739,7 @@ Fold lower case letters to upper case for sorting.
This option provides an alternative (to @samp{-W}) method of describing
which characters make up words. It introduces the name of a
file which contains a list of characters which can@emph{not} be part of
one word, this file is called the @dfn{Break file}. Any character which
one word; this file is called the @dfn{Break file}. Any character which
is not part of the Break file is a word constituent. If both options
@samp{-b} and @samp{-W} are specified, then @samp{-W} has precedence and
@samp{-b} is ignored.
@ -2764,21 +2768,21 @@ default Ignore file, specify @code{/dev/null} instead.
@itemx --only-file=@var{file}
The file associated with this option contains a list of words which will
be retained in concordance output, any word not mentioned in this file
be retained in concordance output; any word not mentioned in this file
is ignored. The file is called the @dfn{Only file}. The file contains
exactly one word in each line; the end of line separation of words is
not subject to the value of the @samp{-S} option.
There is no default for the Only file. In the case there are both an
Only file and an Ignore file, a word will be subject to be a keyword
only if it is given in the Only file and not given in the Ignore file.
Only file and an Ignore file, a word can be a keyword only if it is
given in the Only file and not given in the Ignore file.
@item -r
@itemx --references
On each input line, the leading sequence of non white characters will be
On each input line, the leading sequence of non-white space characters will be
taken to be a reference that has the purpose of identifying this input
line on the produced permuted index. For more information about reference
line in the resulting permuted index. For more information about reference
production, see @xref{Output formatting in ptx}.
Using this option changes the default value for option @samp{-S}.
@ -2793,12 +2797,12 @@ excluded from the output contexts.
@itemx --sentence-regexp=@var{regexp}
This option selects which regular expression will describe the end of a
line or the end of a sentence. In fact, there is other distinction
between end of lines or end of sentences than the effect of this regular
expression, and input line boundaries have no special significance
outside this option. By default, when GNU extensions are enabled and if
@samp{-r} option is not used, end of sentences are used. In this
case, the precise @var{regex} is imported from GNU emacs:
line or the end of a sentence. In fact, this regular expression is not
the only distinction between end of lines or end of sentences, and input
line boundaries have no special significance outside this option. By
default, when GNU extensions are enabled and if @samp{-r} option is not
used, end of sentences are used. In this case, this @var{regex} is
imported from GNU Emacs:
@example
[.?!][]\"')@}]*\\($\\|\t\\| \\)[ \t\n]*
@ -2829,8 +2833,8 @@ the head of the input line or sentence is used to fill the unused area
on the right of the output line.
As a matter of convenience to the user, many usual backslashed escape
sequences, as found in the C language, are recognized and converted to
the corresponding characters by @code{ptx} itself.
sequences from the C language are recognized and converted to the
corresponding characters by @code{ptx} itself.
@item -W @var{regexp}
@itemx --word-regexp=@var{regexp}
@ -2841,9 +2845,9 @@ letters; the @var{regexp} used is @samp{\w+}. When GNU extensions are
disabled, a word is by default anything which ends with a space, a tab
or a newline; the @var{regexp} used is @samp{[^ \t\n]+}.
An empty @var{regexp} is equivalent to not using this option, letting the
default dive in. @xref{Regexps, , Syntax of Regular Expressions, emacs,
The GNU Emacs Manual}.
An empty @var{regexp} is equivalent to not using this option.
@xref{Regexps, , Syntax of Regular Expressions, emacs, The GNU Emacs
Manual}.
As a matter of convenience to the user, many usual backslashed escape
sequences, as found in the C language, are recognized and converted to
@ -2855,13 +2859,13 @@ the corresponding characters by @code{ptx} itself.
@node Output formatting in ptx
@subsection Output formatting
Output format is mainly controlled by @samp{-O} and @samp{-T} options,
described in the table below. When neither @samp{-O} nor @samp{-T} is
selected, and if GNU extensions are enabled, the program choose an
output format suited for a dumb terminal. Each keyword occurrence is
Output format is mainly controlled by the @samp{-O} and @samp{-T} options
described in the table below. When neither @samp{-O} nor @samp{-T} are
selected, and if GNU extensions are enabled, the program chooses an
output format suitable for a dumb terminal. Each keyword occurrence is
output to the center of one line, surrounded by its left and right
contexts. Each field is properly justified, so the concordance output
could readily be observed. As a special feature, if automatic
can be readily observed. As a special feature, if automatic
references are selected by option @samp{-A} and are output before the
left context, that is, if option @samp{-R} is @emph{not} selected, then
a colon is added after the reference; this nicely interfaces with GNU
@ -2879,8 +2883,8 @@ Output format is further controlled by the following options.
@item -g @var{number}
@itemx --gap-size=@var{number}
Select the size of the minimum white gap between the fields on the output
line.
Select the size of the minimum white space gap between the fields on the
output line.
@item -w @var{number}
@itemx --width=@var{number}
@ -2890,7 +2894,7 @@ used, they are included or excluded from the output maximum width
depending on the value of option @samp{-R}. If this option is not
selected, that is, when references are output before the left context,
the output maximum width takes into account the maximum length of all
references. If this options is selected, that is, when references are
references. If this option is selected, that is, when references are
output after the right context, the output maximum width does not take
into account the space taken by references, nor the gap that precedes
them.
@ -2930,12 +2934,12 @@ towards the beginning or the end of the current line, or current
sentence, as selected with option @samp{-S}. But there is a maximum
allowed output line width, changeable through option @samp{-w}, which is
further divided into space for various output fields. When a field has
to be truncated because cannot extend until the beginning or the end of
the current line to fit in the, then a truncation occurs. By default,
to be truncated because it cannot extend beyond the beginning or the end of
the current line to fit in, then a truncation occurs. By default,
the string used is a single slash, as in @samp{-F /}.
@var{string} may have more than one character, as in @samp{-F ...}.
Also, in the particular case @var{string} is empty (@samp{-F ""}),
Also, in the particular case when @var{string} is empty (@samp{-F ""}),
truncation flagging is disabled, and no truncation marks are appended in
this case.
@ -2955,11 +2959,11 @@ generating output suitable for @code{nroff}, @code{troff} or @TeX{}.
Choose an output format suitable for @code{nroff} or @code{troff}
processing. Each output line will look like:
@example
@smallexample
.xx "@var{tail}" "@var{before}" "@var{keyword_and_after}" "@var{head}" "@var{ref}"
@end example
@end smallexample
so it will be possible to write an @samp{.xx} roff macro to take care of
so it will be possible to write a @samp{.xx} roff macro to take care of
the output typesetting. This is the default output format when GNU
extensions are disabled. Option @samp{-M} might be used to change
@samp{xx} to another macro name.
@ -2975,9 +2979,9 @@ so it will be correctly processed by @code{nroff} or @code{troff}.
Choose an output format suitable for @TeX{} processing. Each output
line will look like:
@example
@smallexample
\xx @{@var{tail}@}@{@var{before}@}@{@var{keyword}@}@{@var{after}@}@{@var{head}@}@{@var{ref}@}
@end example
@end smallexample
@noindent
so it will be possible to write a @code{\xx} definition to take care of
@ -3025,11 +3029,11 @@ or, if a second @var{file} parameter is given on the command, to that
Having output parameters not introduced by options is a quite dangerous
practice which GNU avoids as far as possible. So, for using @code{ptx}
portably between GNU and System V, you should pay attention to always
use it with a single input file, and always expect the result on
standard output. You might also want to automatically configure in a
@samp{-G} option to @code{ptx} calls in products using @code{ptx}, if
the configurator finds that the installed @code{ptx} accepts @samp{-G}.
portably between GNU and System V, you should always use it with a
single input file, and always expect the result on standard output. You
might also want to automatically configure in a @samp{-G} option to
@code{ptx} calls in products using @code{ptx}, if the configurator finds
that the installed @code{ptx} accepts @samp{-G}.
@item
The only options available in System V @code{ptx} are options @samp{-b},
@ -3053,7 +3057,7 @@ line width computations.
All 256 characters, even @kbd{NUL}s, are always read and processed from
input file with no adverse effect, even if GNU extensions are disabled.
However, System V @code{ptx} does not accept 8-bit characters, a few
control characters are rejected, and the tilde @kbd{~} is condemned.
control characters are rejected, and the tilde @kbd{~} is also rejected.
@item
Input line length is only limited by available memory, even if GNU
@ -3156,7 +3160,7 @@ character.
@itemx --output-delimiter=@var{output_delim_string}
@opindex --output-delimiter
For @samp{-f}, output fields are separated by @var{output_delim_string}
For @samp{-f}, output fields are separated by @var{output_delim_string}.
The default is to use the input delimiter.
@ -3871,9 +3875,9 @@ water pipeline.
With the Unix shell, it's very easy to set up data pipelines:
@example
@smallexample
program_to_create_data | filter1 | .... | filterN > final.pretty.data
@end example
@end smallexample
We start out by creating the raw data; each filter applies some successive
transformation to the data, until by the time it comes out of the pipeline,
@ -4137,9 +4141,9 @@ The next step is to get rid of punctuation. Quoted words and unquoted words
should be treated identically; it's easiest to just get the punctuation out of
the way.
@example
@smallexample
$ tr '[A-Z]' '[a-z]' < whats.gnu | tr -cd '[A-Za-z0-9_ \012]' | ...
@end example
@end smallexample
The second @code{tr} command operates on the complement of the listed
characters, which are all the letters, the digits, the underscore, and
@ -4152,10 +4156,10 @@ The words only contain alphanumeric characters (and the underscore). The
next step is break the data apart so that we have one word per line. This
makes the counting operation much easier, as we will see shortly.
@example
@smallexample
$ tr '[A-Z]' '[a-z]' < whats.gnu | tr -cd '[A-Za-z0-9_ \012]' |
> tr -s '[ ]' '\012' | ...
@end example
@end smallexample
This command turns blanks into newlines. The @samp{-s} option squeezes
multiple newline characters in the output into just one. This helps us
@ -4166,10 +4170,10 @@ typing in all of a command.)
We now have data consisting of one word per line, no punctuation, all one
case. We're ready to count each word:
@example
@smallexample
$ tr '[A-Z]' '[a-z]' < whats.gnu | tr -cd '[A-Za-z0-9_ \012]' |
> tr -s '[ ]' '\012' | sort | uniq -c | ...
@end example
@end smallexample
At this point, the data might look something like this:
@ -4198,7 +4202,7 @@ reverse the order of the sort
The final pipeline looks like this:
@example
@smallexample
$ tr '[A-Z]' '[a-z]' < whats.gnu | tr -cd '[A-Za-z0-9_ \012]' |
> tr -s '[ ]' '\012' | sort | uniq -c | sort -nr
156 the
@ -4207,7 +4211,7 @@ $ tr '[A-Z]' '[a-z]' < whats.gnu | tr -cd '[A-Za-z0-9_ \012]' |
51 of
51 and
...
@end example
@end smallexample
Whew! That's a lot to digest. Yet, the same principles apply. With six
commands, on two lines (really one long one split for convenience), we've
@ -4225,19 +4229,19 @@ dictionary.
Now, how to compare our file with the dictionary? As before, we generate
a sorted list of words, one per line:
@example
@smallexample
$ tr '[A-Z]' '[a-z]' < whats.gnu | tr -cd '[A-Za-z0-9_ \012]' |
> tr -s '[ ]' '\012' | sort -u | ...
@end example
@end smallexample
Now, all we need is a list of words that are @emph{not} in the
dictionary. Here is where the @code{comm} command comes in.
@example
@smallexample
$ tr '[A-Z]' '[a-z]' < whats.gnu | tr -cd '[A-Za-z0-9_ \012]' |
> tr -s '[ ]' '\012' | sort -u |
> comm -23 - /usr/lib/ispell/ispell.words
@end example
@end smallexample
The @samp{-2} and @samp{-3} options eliminate lines that are only in the
dictionary (the second file), and lines that are in both files. Lines