'\" t
.\" Sccsid @(#)ed.1	1.48 (gritter) 6/22/05
.\" Parts taken from ed(1), Unix 7th edition:
.\" Copyright(C) Caldera International Inc. 2001-2002. All rights reserved.
.\"
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.\"    must display the following acknowledgement:
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.TH ED 1 "6/22/05" "Heirloom Toolchest" "User Commands"
.if t .ds q \(aa
.if n .ds q '
.SH NAME
ed \- text editor
.SH SYNOPSIS
\fBed\fR [\fB\-\fR\ |\ \fB\-s\fR] [\fB\-p\fI\ prompt\fR] [\fIname\fR]
.SH DESCRIPTION
.I Ed
is the standard text editor.
.PP
If a
.I name
argument is given,
.I ed
simulates an
.I e
command (see below)\| on the named file; that is to say,
the file is read into
.IR ed 's
buffer so that it can be edited.
The optional
.B \-
or
.B \-s
suppresses the printing
of character counts by
.IR e ,
.IR r ,
and
.I w
commands,
and of the `!' after completion of a shell command.
.PP
With the
.B \-p
option,
the given
.I prompt
string is printed before each command is read.
.PP
.I Ed
operates on a copy of any file it is editing; changes made
in the copy have no effect on the file until a
.IR w ""
(write)\|
command is given.
The copy of the text being edited resides
in a temporary file called the 
.IR buffer .
.PP
The editor supports format specifications as defined in
.IR fspec (5).
If the terminal is configured to expand tabulators
(as enabled with
.I stty tab3
or
.IR "stty \-tabs"),
and the first line of the file being edited
contains a format specification,
the
.I t
and
.I s
are interpreted,
that is, tabulators are expanded and lines are truncated
when printing to the terminal. For example,
.RS
<:t\-f s72:>
.sp
.RE
selects FORTRAN format and truncates lines at 72 characters.
No expansion or truncation is performed by
.I ed
when input is typed to the terminal.
.PP
Commands to
.I ed
have a simple and regular structure: zero or
more
.I addresses
followed by a single character
.I command,
possibly
followed by parameters to the command.
These addresses specify one or more lines in the buffer.
Missing addresses are supplied by default.
.PP
In general, only one command may appear on a line.
Certain commands allow the 
addition of text to the buffer.
While
.I ed
is accepting text, it is said
to be in
.I  "input mode."
In this mode, no commands are recognized;
all input is merely collected.
Input mode is left by typing a period `\fB.\fR' alone at the
beginning of a line.
.PP
.I Ed
supports a limited form of
.I "regular expression"
notation.
A regular expression specifies
a set of strings of characters.
A member of this set of strings is said to be
.I matched
by the regular expression.
In the following specification for regular expressions
the word `character' means any character but newline.
.B /usr/5bin/ed
uses simple regular expressions,
whereas
.BR /usr/5bin/s42/ed ,
.BR /usr/5bin/posix/ed ,
and
.B /usr/5bin/posix2001/ed
use basic regular expressions.
.SS "Simple Regular Expressions"
.IP 1.
Any character except a special character
matches itself.
Special characters are
the regular expression delimiter plus
.RB \e\|[\| .
and sometimes ^\|*\|$.
.IP 2.
A
.B .\&
matches any character.
.IP 3.
A \fB\e\fR followed by any character except a digit
or (\|) {\|} <\|> matches that character.
.IP 4.
A nonempty string
.I s
bracketed
\fB[\fI\|s\|\fB]\fR
(or
\fB[^\fIs\|\fB]\fR)
forms a \fIbracket expression\fR that
matches any character in (or not in)
.I s.
In 
.I s,
\e has no special meaning, and ] may only appear as
the first letter.
A substring 
\fIa\fB\-\fIb\fR,
with
.I a
and
.I b
in ascending ASCII order, stands for the inclusive
range of ASCII characters.
.IP 5.
A regular expression of form 1-4 followed by \fB*\fR matches a sequence of
0 or more matches of the regular expression.
.IP 6.
A regular expression of form 1-4
followed by \fB\e{\fIm\fB,\fIn\fB\e}\fR
forms an \fIinterval expression\fR that
matches a sequence of \fIm\fR through \fIn\fR matches, inclusive,
of the regular expression.
The values of \fIm\fR and \fIn\fR must be non-negative
and smaller than 256.
The form \fB\e{\fIm\fB\e}\fR matches exactly \fIm\fR occurrences,
\fB\e{\fIm\fB,\e}\fR matches at least \fIm\fR occurrences.
.IP 7.
The sequence \fB\e<\fR forces the match
to occur only at the beginning of a ``variable'' or ``word'';
that is, either at the beginning of a line,
or just before a letter, digit or underline
and after a character not one of these.
.IP 8.
The sequence \fB\e>\fR matches the end
of a ``variable'' or ``word'',
i.\|e. either the end of the line
or before character which is neither a letter,
nor a digit, nor the underline character.
.IP 9.
A regular expression,
.I x,
of form 1-11, parenthesized
\fB\e(\fI\|x\|\fB\e)\fR
is called a \fIsubexpression\fR and
matches what
.I x
matches.
.IP 10.
A \fB\e\fR followed by a digit 
.I n
forms a \fIbackreference\fR and
matches a copy of the string that the
parenthesized regular expression beginning with the
.IR n th
\e( matched.
.IP 11.
A regular expression of form 1-11,
.I x,
followed by a regular expression of form 1-10,
.I y
matches a match for
.I x
followed by a match for
.I y,
with the
.I x
match being as long as possible while still permitting a
.I y
match.
.IP 12.
A regular expression of form 1-11 preceded by \fB^\fR
(or followed by \fB$\fR), is constrained to matches that
begin at the left (or end at the right) end of a line
(\fIanchoring\fR).
.IP 13.
A regular expression of form 1-12 picks out the
longest among the leftmost matches in a line.
.IP 14.
An empty regular expression stands for a copy of the
last regular expression encountered.
.SS "Basic Regular Expressions"
Basic Regular Expressions add the following features
to Simple Regular Expressions:
.IP 15.
The special character \fB*\fR, as described in 5.,
and the interval expressions described in 6.
can also be applied to subexpressions
as described in 9.
For POSIX.1-2001 utilities such as
.BR /usr/5bin/posix2001/ed ,
subexpressions do not match the empty string
if there is a possible longer match.
.IP 16.
In bracket expressions as described in 4.,
the following character sequences are considered special:
.IP
Character class expressions of the form
\fB[:\fIclass\fB:]\fR.
In the C LC_CTYPE locale,
the classes
.sp
.TS
l l l l.
[:alnum:]	[:cntrl:]	[:lower:]	[:space:]
[:alpha:]	[:digit:]	[:print:]	[:upper:]
[:blank:]	[:graph:]	[:punct:]	[:xdigit:]
.TE
.sp
are recognized;
further locale-specific classes may be available.
A character class expression matches any character
that belongs to the given class in the current LC_CTYPE locale.
.IP
Collating symbol expressions of the form
\fB[.\fIc\fB.]\fR,
where \fIc\fR is a collating symbol
in the current LC_COLLATE locale.
A collating symbol expression
matches the specified collating symbol.
.IP
Equivalence class expressions of the form
\fB[=\fIc\fB=]\fR,
where \fIc\fR is a collating symbol
in the current LC_COLLATE locale.
An equivalence class expression
matches any character that has the same collating weight
as \fIc\fR.
.PP
Regular expressions are used in addresses to specify
lines and in one command
(see
.I s
below)\|
to specify a portion of a line which is to be replaced.
If it is desired to use one of
the regular expression metacharacters as an ordinary
character, that character may be preceded by `\e'.
This also applies to the character bounding the regular
expression (often `/')\| and to `\e' itself.
.PP
To understand addressing in
.I ed
it is necessary to know that at any time there is a
.I  "current line."
Generally speaking, the current line is
the last line affected by a command; however,
the exact effect on the current line
is discussed under the description of
the command.
Addresses are constructed as follows.
.TP
1.
The character `\fB.\fR' addresses the current line.
.TP
2.
The character `\fB$\fR' addresses the last line of the buffer.
.TP
3.
A decimal number
.I n
addresses the
.IR n -th
line of the buffer.
.TP
4.
`\fB\(fm\fIx\fR' addresses the line marked with the name
.IR x ,
which must be a lower-case letter.
Lines are marked with the
.I k
command described below.
.TP
5.
A regular expression enclosed in slashes `\fB/\fR' addresses
the line found by searching forward from the current line
and stopping at the first line containing a
string that matches the regular expression.
If necessary the search wraps around to the beginning of the
buffer.
.TP
6.
A regular expression enclosed in queries `\fB?\fR' addresses
the line found by searching backward from the current line
and stopping at the first line containing
a string that matches the regular expression.
If necessary
the search wraps around to the end of the buffer.
.TP
7.
An address followed by a plus sign `\fB+\fR'
or a minus sign `\fB\-\fR' followed by a decimal number
specifies that address plus
(resp. minus)\| the indicated number of lines.
The plus sign may be omitted.
.TP
8.
If an address begins with `\fB+\fR' or `\fB\-\fR'
the addition or subtraction is taken with respect to the current line;
e.g. `\-5' is understood to mean `\fB.\fR\-5'.
.TP
9.
If an address ends with `\fB+\fR' or `\fB\-\fR',
then 1 is added (resp. subtracted).
As a consequence of this rule and rule 8,
the address `\-' refers to the line before the current line.
Moreover,
trailing
`+' and `\-' characters
have cumulative effect, so `\-\-' refers to the current
line less 2.
.TP
10.
To maintain compatibility with earlier versions of the editor,
the character `\fB^\fR' in addresses is 
equivalent to `\-'.
.PP
Commands may require zero, one, or two addresses.
Commands which require no addresses regard the presence
of an address as an error.
Commands which accept one or two addresses
assume default addresses when insufficient are given.
If more addresses are given than such a command requires,
the last one or two (depending on what is accepted)\| are used.
.PP
Addresses are separated from each other typically by a comma
`\fB,\fR'.
They may also be separated by a semicolon
`\fB;\fR'.
In this case the current line `\fB.\fR' is set to
the previous address before the next address is interpreted.
This feature can be used to determine the starting
line for forward and backward searches (`/', `?')\|.
The second address of any two-address sequence
must correspond to a line following the line corresponding to the first address.
.PP
Omission of the first address causes
the first line to be used with `,',
or the current line with `;', respectively;
if the second address is also omitted,
the last line of the buffer is used.
Thus a single `,' specifies the entire contents of the buffer,
and a single `;' specifies the contents
ranging from the current line to the last one.
.PP
In the following list of
.I ed
commands, the default addresses
are shown in parentheses.
The parentheses are not part of
the address, but are used to show that the given addresses are
the default.
.PP
As mentioned, it is generally illegal for more than one
command to appear on a line.
However, most commands may be suffixed by `p', `l', or `n',
in which case
the current line is either
printed, listed, or numbered respectively
in the way discussed below.
.TP 5
\fR(\|\fI.\|\fR)\fB\|a\fR
.br
.ns
.TP 5
<text>
.br
.ns
.TP 5
.B .
.br
The append command reads the given text
and appends it after the addressed line.
`\fB.\fR' is left
on the last line input, if there
were any, otherwise at the addressed line.
Address `0' is legal for this command; text is placed
at the beginning of the buffer.
.TP 5
\fR(\|\fI.\|\fB,\|\fI.\|\fR)\|\fBc\fR
.br
.ns
.TP 5
<text>
.br
.ns
.TP 5
.B .
.br
The change
command deletes the addressed lines, then accepts input
text which replaces these lines.
`\fB.\fR' is left at the last line input; if there were none,
it is left at the line preceding the deleted lines.
For
.BR /usr/5bin/posix2001/ed ,
a `0' as the first address is identical to `1'.
.TP 5
\fR(\|\fI.\|\fB,\|\fI.\|\fR)\|\fBd\fR
The delete command deletes the addressed lines from the buffer.
The line originally after the last line deleted becomes the current line;
if the lines deleted were originally at the end,
the new last line becomes the current line.
.TP 5
\fBe\ \fIfilename\fR
The edit
command causes the entire contents of the buffer to be deleted,
and then the named file to be read in.
`\fB.\fR' is set to the last line of the buffer.
The number of characters read is typed.
`\fIfilename\fR' is remembered for possible use as a default file name
in a subsequent
.I r
or
.I w
command.
If `\fIfilename\fR' is missing, the remembered name is used.
A `\fIfilename\fR' starting with a `\fB!\fR'
causes the output of the shell command following this character
to be read in.
.TP 5
\fBE\ \fIfilename\fR
This command is the same as
.IR e ,
except that no diagnostic results when no
.I w
has been given since the last buffer alteration.
.TP 5
\fBf\ \fIfilename\fR
The filename command prints the currently remembered file name.
If `\fIfilename\fR' is given,
the currently remembered file name is changed to `\fIfilename\fR'.
.TP 5
\fR(\fI1\fB,\fI$\fR)\|\fBg/\fIregular expression\fB/\fIcommand list\fR
In the global
command, the first step is to mark every line which matches
the given \fIregular expression\fR.
Then for every such line, the
given \fIcommand list\fR is executed
with `\fB.\fR' initially set to that line.
A single command or the first of multiple commands
appears on the same line with the global command.
All lines of a multi-line list except the last line must be ended with `\e'.
.I A,
.I i,
and
.I c
commands and associated input are permitted;
the `\fB.\fR' terminating input mode may be omitted if it would be on the
last line of the command list.
The commands
.I g
and
.I v
are not permitted in the command list.
.TP 5
\fR(\fI1\fB,\fI$\fR)\|\fBG/\fIregular expression\fB/\fR
The interactive global command
first marks every line matching the given \fIregular expression\fR.
Then each line is printed
and a command is read and executed for this line.
A single newline character causes the line to remain unchanged,
an isolated `\fB&\fR' repeats the command given for the previous line.
The command can be terminated by an interrupt signal.
.TP 5
.B h
This command prints a verbose description for the
last error encountered.
.TP
.B H
This command acts like the
.I h
command,
but also causes verbose descriptions to be printed
on all following error conditions.
Another
.I H
turns verbose mode off.
.TP 5
\fR(\|\fI.\|\fR)\|\fBi\fR
.br
.ns
.TP 5
<text>
.br
.ns
.TP 5
.B .
.br
This command inserts the given text before the addressed line.
`\fB.\fR' is left at the last line input, or, if there were none,
at the line before the addressed line.
This command differs from the
.I a
command only in the placement of the
text.
For
.BR /usr/5bin/posix2001/ed ,
a `0' as the first address is identical to `1'.
.TP 5
\fR(\|\fI.\|\fB,\|\fI.+1\fR)\|\fBj\fR
This command joins the addressed lines into a single line;
intermediate newlines simply disappear.
`\fB.\fR' is left at the resulting line.
.TP 5
\fR(\fI.\fR)\|\fBk\fIx\fR
The mark command marks the addressed line with
name
.IR x ,
which must be a lower-case letter.
The address form `\(fm\fIx\fR' then addresses this line.
.ne 2.5
.TP 5
\fR(\|\fI.\|\fB,\|\fI.\|\fR)\|\fBl\fR
The list command
prints the addressed lines in an unambiguous way:
.B /usr/5bin/ed
prints
non-graphic control characters in three-digit octal;
.BR /usr/5bin/s42/ed ,
.BR /usr/5bin/posix/ed ,
and
.B /usr/5bin/posix2001/ed
print control characters as C-style escape sequences
or in three-digit octal.
Long lines are folded.
The
.I l
command may be placed on the same line after any non-i/o
command.
.TP 5
\fR(\|\fI.\|\fB,\|\fI.\|\fR)\|\fBm\fIa\fR
The move command repositions the addressed lines after the line
addressed by
.IR a .
The last of the moved lines becomes the current line.
.TP 5
\fR(\|\fI.\|\fB,\|\fI.\|\fR)\|\fBn\fR
This command prints lines preceded by their line numbers.
It otherwise acts like the
.I p
command described below.
.TP 5
\fR(\|\fI.\|\fB,\|\fI.\|\fR)\|\fBp\fR
The print command prints the addressed lines.
`\fB.\fR'
is left at the last line printed.
The
.I p
command
may
be placed on the same line after any non-i/o command.
.TP
.B P
This command causes a prompt to be printed
before following commands are read.
The default prompt is a `*' character,
but can be set with the
.I \-p
command line option (which also enables the prompt).
Another 
.I P
disables the prompt.
.TP 5
.B q
The quit command causes
.I ed
to exit.
No automatic write
of a file is done.
.TP 5
.B Q
This command is the same as
.I q,
except that no diagnostic results when no
.I w
has been given since the last buffer alteration.
.TP 5
\fR(\fI$\fR)\|\fBr\ \fIfilename\fR
The read command
reads in the given file after the addressed line.
If no file name is given,
the remembered file name, if any, is used
(see
.I e
and
.I f
commands)\|.
The file name is remembered if there was no
remembered file name already.
Address `0' is legal for
.I r
and causes the
file to be read at the beginning of the buffer.
If the read is successful, the number of characters
read is typed.
`\fB.\fR' is left at the last line read in from the file.
A `filename' starting with a `\fB!\fR'
causes the output of the shell command following this character
to be read in.
.TP 5
\fR(\|\fI.\fB\|,\|\fI.\fR\|)\|\fBs/\fIregular expression\fB/\fIreplacement\fB/\fR       or,
.br
.ns
.TP 5
\fR(\|\fI.\fB\|,\|\fI.\fR\|)\|\fBs/\fIregular expression\fB/\fIreplacement\fB/g\fR      or,
.br
.ns
.TP 5
\fR(\|\fI.\fB\|,\|\fI.\fR\|)\|\fBs/\fIregular expression\fB/\fIreplacement\fB/\fInumber\fR
The substitute command searches each addressed
line for an occurrence of the specified regular expression.
On each line in which a match is found,
all matched strings are replaced by the replacement specified,
if the global replacement indicator
.RB ` g '
appears after the command.
If the global indicator does not appear, only the first occurrence
of the matched string is replaced;
if the \fInumber\fR indicator is given,
the numbered occurrence is replaced.
It is an error for the substitution to fail on all addressed lines.
Any character other than space or new-line
may be used instead of `/' to delimit the regular expression
and the replacement.
`\fB.\fR' is left at the last line substituted.
.IP
An ampersand
.RB ` & '
appearing in the replacement
is replaced by the string matching the regular expression.
The special meaning of `&' in this context may be
suppressed by preceding it by
.RB ` \e '.
The characters `\|\fB\e\fIn\fR'
where
.I n
is a digit,
are replaced by the text matched by the
.IR n -th
regular subexpression
enclosed between `\e(' and `\e)'.
When
nested, parenthesized subexpressions
are present,
.I n
is determined by counting occurrences of `\e(' starting from the left.
.IP
A substitution string consisting of a single
.RB ` % '
causes the string given on the previous substitution to be re-used.
.IP
Lines may be split by substituting new-line characters into them.
The new-line in the
replacement string
must be escaped by preceding it by
.RB ` \e '.
.TP 5
\fR(\|\fI.\|\fB,\|\fI.\|\fR)\|\fBt\|\fIa\fR
This command acts just like the
.I m
command, except that a copy of the addressed lines is placed
after address
.I a
(which may be 0).
`\fB.\fR' is left on the last line of the copy.
.TP 5
.B u
The undo command restores
the contents of the buffer
before the last command was executed.
If the undo command is given twice,
the current state is restored.
.TP 5
\fR(\fI1\fB,\fI$\fR)\|\fBv/\fIregular expression\fB/\fIcommand list\fR
This command is the same as the global command
.I g
except that the command list is executed
.I g
with `\fB.\fR' initially set to every line
.I except
those
matching the regular expression.
.TP 5
\fR(\fI1\fB,\fI$\fR)\|\fBV/\fIregular expression\fB/\fR
This command is the same as the interactive global command
.I G
except that the commands are read
.I g
with `\fB.\fR' initially set to every line
.I except
those
matching the regular expression.
.TP 5
\fR(\fI1\fB,\fI$\fR)\|\fBw\ \fIfilename\fR
.br
The write command writes the addressed lines onto
the given file.
If the file does not exist,
it is created mode 666 (readable and writable by everyone)\|.
The file name is remembered if there was no 
remembered file name already.
If no file name is given,
the remembered file name, if any, is used
(see
.I e
and
.I f
commands)\|.
`\fB.\fR' is unchanged.
If the command is successful, the number of characters written is
printed.
A `filename' starting with a `\fB!\fR'
causes the string following this character
to be executed as a shell command
with the addressed lines as standard input.
.TP
\fR(\fI1\fB,\fI$\fR)\fBW\ \fIfilename\fR
This command is the same as
.I w,
except that the addressed lines are appended to the file.
.TP 5
\fR(\fI$\fR)\|\fB=\fR
The line number of the addressed line is typed.
`\fB.\fR' is unchanged by this command.
.TP 5
\fB!\fR<shell command>
The remainder of the line after the `!' is sent
to
.IR sh (1)
to be interpreted as a command.
.RB ` . '
is unchanged.
If the command starts with a
.RB ` ! ',
the previous command is inserted.
A
.RB ` % '
causes the current file name to be inserted.
.TP 5
\fR(\|\fI.+1\fR)\|<newline>
An address alone on a line causes the addressed line to be printed.
A blank line alone is equivalent to `.+1p'; it is useful
for stepping through text.
.PP
The following commands are extensions:
.TP 5
\fR(\|\fI.\|\fR)\fB\|b\fR[\fIcount\fR]
Prints a screenful of lines,
starting at the addressed one,
and browses forward in the buffer by this amount.
With the optional
.I count
argument, the screen size for this and following
.I b
commands is set to the given number of lines.
.TP 5
.B help
Causes a summary of
.I ed
commands along with short descriptions
to be printed on the terminal.
.TP 5
.B N
Makes the
.I p
command behave like the
.I n
command and vice-versa.
If given a second time,
the original semantics are restored.
.TP 5
\fR(\|\fI.\|\fR)\fB\|o\fR[\fIcount\fR]
Prints a screenful of lines centered around the addressed one.
The current line is not changed.
With the optional
.I count
argument, the amount of lines printed above and below
for this and following
.I o
commands is set to the given number.
.TP 5
.B z
Performs the same actions as a
.I w
command followed by a
.I q
command.
.PP
If an interrupt signal is sent,
.I ed
prints a `?' and returns to its command level.
.PP
An input line that consists exactly of the two characters `\e.'
causes a period `.' to be inserted with the
.IR a ,
.IR c ,
and
.IR i
commands
in
.B /usr/5bin/ed
and
.BR /usr/5bin/s42/ed .
.PP
Some size limitations:
The maximum number of bytes in the buffer
corresponds to the address size;
on machines with 32-bit addressing,
it is 2\ G bytes,
with 64-bit addressing,
it is 9\ E bytes.
The limit on the number of lines depends on the amount of core:
each line takes 2 words.
.PP
If a line contains a NUL character,
regular expressions cannot match beyond this character.
A substitute command deletes a NUL
and all following characters on the line.
NUL characters in command input are discarded.
If an input file does not end with a newline,
.I ed
prints a message and appends one.
.PP
Omission of the `/' character
following the regular expression or the replacement string
to the global and substitute commands
causes the affected lines to be printed.
Thus the following commands have the same effect:
.RS
g/pattern	g/pattern/p
.br
s/pattern/repl	s/pattern/repl/p
.br
s/pattern/	s/pattern//p
.RE
.SH "ENVIRONMENT VARIABLES"
.TP
.BR LANG ", " LC_ALL
See
.IR locale (7).
.TP
.B LC_COLLATE
Affects the collation order for range expressions,
equivalence classes, and collation symbols
in basic regular expressions.
.TP
.B LC_CTYPE
Determines the mapping of bytes to characters
in both simple and basic regular expressions,
the availability and composition of character classes
in basic regular expressions,
and the set of printable characters for the
.I l
command.
.TP
.B TMPDIR
Determines the location of the temporary file
if it contains the name of an accessible directory.
.SH FILES
/var/tmp/e*
.br
/tmp/e*
.br
ed.hup: work is saved here if terminal hangs up
.SH "SEE ALSO"
B. W. Kernighan,
.I
A Tutorial Introduction to the ED Text Editor
.br
B. W. Kernighan,
.I Advanced editing on UNIX
.br
bfs(1),
grep(1),
sed(1),
sh(1)
.SH DIAGNOSTICS
`?name' for inaccessible file;
`?' for
errors in commands,
possibly followed by a verbose description
(see the description for the
.I h
and
.I H
commands above).
.PP
To protect against throwing away valuable work,
a
.I q
or
.I e
command is considered to be in error, unless a
.I w
has occurred since the last buffer change.
A second
.I q
or
.I e
will be obeyed regardless.
.SH NOTES
A
.I !\&
command cannot be subject to a
.I g
command.
.PP
The LC_COLLATE variable has currently no effect.
Ranges in bracket expressions are ordered
as byte values in single-byte locales
and as wide character values in multibyte locales;
equivalence classes match the given character only,
and multi-character collating elements are not available.
.PP
For portable programs, restrict textual data
to the US-ASCII character set,
set the LC_CTYPE and LC_COLLATE variables to `C' or `POSIX',
and use the constructs in the second column
instead of the character class expressions as follows:
.RS 
.sp
.TS
l l.
[[:alnum:]]	[0\-9A\-Za\-z]
[[:alpha:]]	[A\-Za\-z]
[[:blank:]]	[\fI<tab><space>\fR]
[[:cntrl:]]	[^\fI<space>\fR\-~]
[[:digit:]]	[0\-9]
[[:graph:]]	[!\-~]
[[:lower:]]	[a\-z]
[[:print:]]	[\fI<space>\fR\-~]
[[:punct:]]	[!\-/:\-@[\-`{\-~]
[[:space:]]	[\fI<tab><vt><ff><cr><space>\fR]
[[:upper:]]	[A\-Z]
[[:xdigit:]]	[0\-9a\-fA\-F]
.TE
.sp
.RE
.IR <tab> ,
.IR <space> ,
.IR <vt> ,
.IR <ff> ,
and
.I <cr>
indicate inclusion of
a literal tabulator, space, vertical tabulator, formfeed,
or carriage return character, respectively.
Do not put the
.IR <vt> ,
.IR <ff> ,
and
.I <cr>
characters into the range expression for the
.I space
class unless you actually want to match these characters.