.\"
.\" Sun Microsystems, Inc. gratefully acknowledges The Open Group for
.\" permission to reproduce portions of its copyrighted documentation.
.\" Original documentation from The Open Group can be obtained online at
.\" http://www.opengroup.org/bookstore/.
.\"
.\" The Institute of Electrical and Electronics Engineers and The Open
.\" Group, have given us permission to reprint portions of their
.\" documentation.
.\"
.\" In the following statement, the phrase ``this text'' refers to portions
.\" of the system documentation.
.\"
.\" Portions of this text are reprinted and reproduced in electronic form
.\" in the SunOS Reference Manual, from IEEE Std 1003.1, 2004 Edition,
.\" Standard for Information Technology -- Portable Operating System
.\" Interface (POSIX), The Open Group Base Specifications Issue 6,
.\" Copyright (C) 2001-2004 by the Institute of Electrical and Electronics
.\" Engineers, Inc and The Open Group.  In the event of any discrepancy
.\" between these versions and the original IEEE and The Open Group
.\" Standard, the original IEEE and The Open Group Standard is the referee
.\" document.  The original Standard can be obtained online at
.\" http://www.opengroup.org/unix/online.html.
.\"
.\" This notice shall appear on any product containing this material.
.\"
.\" The contents of this file are subject to the terms of the
.\" Common Development and Distribution License (the "License").
.\" You may not use this file except in compliance with the License.
.\"
.\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
.\" or http://www.opensolaris.org/os/licensing.
.\" See the License for the specific language governing permissions
.\" and limitations under the License.
.\"
.\" When distributing Covered Code, include this CDDL HEADER in each
.\" file and include the License file at usr/src/OPENSOLARIS.LICENSE.
.\" If applicable, add the following below this CDDL HEADER, with the
.\" fields enclosed by brackets "[]" replaced with your own identifying
.\" information: Portions Copyright [yyyy] [name of copyright owner]
.\"
.\"
.\" Copyright 1989 AT&T
.\" Portions Copyright (c) 1992, X/Open Company Limited.  All Rights Reserved.
.\" Copyright (c) 2003, Sun Microsystems, Inc.
.\"
.TH ED 1 "Dec 10, 2003"
.SH NAME
ed, red \- text editor
.SH SYNOPSIS
.LP
.nf
\fB/usr/bin/ed\fR [\fB-s\fR | \fB-\fR] [\fB-p\fR \fIstring\fR] [\fB-x\fR] [\fB-C\fR] [\fIfile\fR]
.fi

.LP
.nf
\fB/usr/xpg4/bin/ed\fR [\fB-s\fR | \fB-\fR] [\fB-p\fR \fIstring\fR] [\fB-x\fR] [\fB-C\fR] [\fIfile\fR]
.fi

.LP
.nf
\fB/usr/xpg6/bin/ed\fR [\fB-s\fR | \fB-\fR] [\fB-p\fR \fIstring\fR] [\fB-x\fR] [\fB-C\fR] [\fIfile\fR]
.fi

.LP
.nf
\fB/usr/bin/red\fR [\fB-s\fR | \fB-\fR] [\fB-p\fR \fIstring\fR] [\fB-x\fR] [\fB-C\fR] [\fIfile\fR]
.fi

.SH DESCRIPTION
.sp
.LP
The \fBed\fR utility is the standard text editor. If \fIfile\fR is specified,
\fBed\fR simulates an \fBe\fR command (see below) on the named file. That is,
the file is read into \fBed\fR's buffer so that it can be edited.
.sp
.LP
The \fBed\fR utility operates on a copy of the file it is editing. Changes made
to the copy have no effect on the file until a \fBw\fR (write) command is
given. The copy of the text being edited resides in a temporary file called the
\fIbuffer\fR. There is only one buffer.
.sp
.LP
The \fBred\fR utility is a restricted version of \fBed\fR. It will only allow
editing of files in the current directory. \fBred\fR prohibits executing shell
commands via \fB!\fR\fIshell command\fR. Attempts to bypass these restrictions
result in an error message (\fIrestricted shell\fR).
.sp
.LP
Both \fBed\fR and \fBred\fR support the \fBfspec\fR(5) formatting capability.
The default terminal mode is either \fBstty\fR \fB-tabs\fR or \fBstty tab3\fR,
where tab stops are set at eight columns (see \fBstty\fR(1)). If, however, the
first line of \fIfile\fR contains a format specification, that specification
will override the default mode. For example, tab stops would be set at 5, 10,
and 15, and a maximum line length of 72 would be imposed if the first line of
\fIfile\fR contains
.sp
.in +2
.nf
\fB<:t5,10,15 s72:>\fR
.fi
.in -2
.sp

.sp
.LP
Commands to \fBed\fR have a simple and regular structure: zero, one, or two
\fIaddresses\fR followed by a single-character \fIcommand\fR, possibly followed
by parameters to that command. These addresses specify one or more lines in the
buffer. Every command that requires addresses has default addresses, so that
the addresses can very often be omitted.
.sp
.LP
In general, only one command may appear on a line. Certain commands allow the
input of text. This text is placed in the appropriate place in the buffer.
While \fBed\fR is accepting text, it is said to be in \fIinput mode\fR. In this
mode, \fBno\fR commands are recognized; all input is merely collected. Leave
input mode by typing a period (\fB\&.\fR) at the beginning of a line, followed
immediately by a carriage return.
.sp
.LP
If \fBed\fR executes commands with arguments, it uses the default shell
\fB/usr/bin/sh\fR (see \fBsh\fR(1)).
.SS "Regular Expressions"
.sp
.LP
The \fBed\fR utility supports a limited form of \fIregular expression\fR
notation. Regular expressions are used in addresses to specify lines and in
some commands (for example, \fBs\fR) to specify portions of a line that are to
be substituted. To understand addressing in \fBed\fR, it is necessary to know
that at any time there is a \fIcurrent line\fR. Generally speaking, the current
line is the last line affected by a command. The exact effect on the current
line is discussed under the description of each command.
.sp
.LP
Internationalized Basic Regular Expressions are used for all system-supplied
locales. See \fBregex\fR(7).
.SS "ed Commands"
.sp
.LP
Commands may require zero, one, or two addresses. Commands that require no
addresses regard the presence of an address as an error. Commands that accept
one or two addresses assume default addresses when an insufficient number of
addresses is given; if more addresses are given than such a command requires,
the last one(s) are used.
.sp
.LP
Typically, addresses are separated from each other by a comma (\fB,\fR). They
may also be separated by a semicolon (\fB;\fR). In the latter case, the first
address is calculated, the current line (\fB\&.\fR) is set to that value, and
then the second address is calculated. This feature can be used to determine
the starting line for forward and backward searches (see Rules 5 and 6, above).
The second address of any two-address sequence must correspond to a line in the
buffer that follows the line corresponding to the first address.
.sp
.LP
For \fB/usr/xpg6/gbin/ed\fR, the address can be omitted on either side of the
comma or semicolon separator, in which case the resulting address pairs are as
follows:
.sp

.sp
.TS
box;
c | c
l | l .
Specified	Resulting
_
,	1 , $
_
, addr	1 , addr
_
addr ,	addr , addr
_
;	1 ; $
_
; addr	1 ; addr
_
addr ;	addr ; addr
.TE

.sp
.LP
Any <\fIblank\fR>s included between addresses, address separators, or address
offsets are ignored.
.sp
.LP
In the following list of \fBed\fR commands, the parentheses shown prior to the
command are \fInot\fR part of the address. Rather, the parentheses show the
default address(es) for the command.
.sp
.LP
Each address component can be preceded by zero or more blank characters. The
command letter can be preceded by zero or more blank characters. If a suffix
letter (\fBl\fR, \fBn\fR, or \fBp\fR) is given, it must immediately follow the
command.
.sp
.LP
The \fBe\fR, \fBE\fR, \fBf\fR, \fBr\fR, and \fBw\fR commands take an optional
\fIfile\fR parameter, separated from the command letter by one or more blank
characters.
.sp
.LP
If changes have been made in the buffer since the last \fBw\fR command that
wrote the entire buffer, \fBed\fR warns the user if an attempt is made to
destroy the editor buffer via the \fBe\fR or \fBq\fR commands. The \fBed\fR
utility writes the string:
.sp
.in +2
.nf
"?\en"
.fi
.in -2
.sp

.sp
.LP
(followed by an explanatory message if \fIhelp mode\fR has been enabled via the
\fBH\fR command) to standard output and continues in command mode with the
current line number unchanged. If the \fBe\fR or \fBq\fR command is repeated
with no intervening command, \fBed\fR takes effect.
.sp
.LP
If an end-of-file is detected on standard input when a command is expected, the
\fBed\fR utility acts as if a \fBq\fR command had been entered.
.sp
.LP
It is generally illegal for more than one command to appear on a line. However,
any command (except \fBe\fR, \fBf\fR, \fBr\fR, or \fBw\fR) may be suffixed by
\fBl\fR, \fBn\fR, or \fBp\fR in which case the current line is either listed,
numbered or written, respectively, as discussed below under the \fBl\fR,
\fBn\fR, and \fBp\fR commands.
.sp
.ne 2
.na
\fB\fB(.)a\fR\fR
.ad
.br
.na
\fB<\fItext\fR> \fR
.ad
.br
.na
\fB\fB\&.\fR\fR
.ad
.RS 11n
The \fBa\fRppend command accepts zero or more lines of text and appends it
after the addressed line in the buffer. The current line (\fB\&.\fR) is left at
the last inserted line, or, if there were none, at the addressed line. Address
0 is legal for this command: it causes the ``appended'' text to be placed at
the beginning of the buffer. The maximum number of characters that may be
entered from a terminal is 256 per line (including the new-line character).
.RE

.sp
.ne 2
.na
\fB\fB(.,.)c\fR\fR
.ad
.br
.na
\fB<\fItext\fR>\fR
.ad
.br
.na
\fB\fB\&.\fR\fR
.ad
.RS 11n
The \fBc\fRhange command deletes the addressed lines from the buffer, then
accepts zero or more lines of text that replaces these lines in the buffer. The
current line (\fB\&.\fR) is left at the last line input, or, if there were
none, at the first line that was not deleted. If the lines deleted were
originally at the end of the buffer, the current line number will be set to the
address of the new last line. If no lines remain in the buffer, the current
line number will be set to 0.
.sp
.ne 2
.na
\fB\fB/usr/xpg4/bin/ed\fR\fR
.ad
.RS 20n
Address 0 is not legal for this command.
.RE

.sp
.ne 2
.na
\fB\fB/usr/xpg6/bin/ed\fR\fR
.ad
.RS 20n
Address 0 is valid for this command. It is interpreted as if the address 1 were
specified.
.RE

.RE

.sp
.ne 2
.na
\fB\fBC\fR\fR
.ad
.RS 11n
Same as the \fBX\fR command, described later, except that \fBed\fR assumes all
text read in for the \fBe\fR and \fBr\fR commands is encrypted unless a null
key is typed in.
.RE

.sp
.ne 2
.na
\fB\fB(.,.)d\fR\fR
.ad
.RS 11n
The \fBd\fRelete command deletes the addressed lines from the buffer. The line
after the last line deleted becomes the current line. If the lines deleted were
originally at the end of the buffer, the new last line becomes the current
line. If no lines remain in the buffer, the current line number will be set to
0.
.RE

.sp
.ne 2
.na
\fB\fBe\fR \fIfile\fR\fR
.ad
.RS 11n
The \fBe\fRdit command deletes the entire contents of the buffer and then reads
the contents of \fIfile\fR into the buffer. The current line (\fB\&.\fR) is set
to the last line of the buffer. If \fIfile\fR is not given, the currently
remembered file name, if any, is used (see the \fBf\fR command). The number of
bytes read will be written to standard output, unless the \fB-s\fR option was
specified, in the following format:
.sp
\fB"%d\en"\fR <\fInumber of bytes read\fR>
.sp
\fIfile\fR is remembered for possible use as a default file name in subsequent
\fBe\fR, \fBE\fR, \fBr\fR, and \fBw\fR commands. If \fIfile\fR is replaced by
\fB!\fR, the rest of the line is taken to be a shell ( \fBsh\fR(1)) command
whose output is to be read. Such a shell command is \fInot\fR remembered as the
current file name.  See also DIAGNOSTICS below. All marks are discarded upon
the completion of a successful \fBe\fR command. If the buffer has changed since
the last time the entire buffer was written, the user is warned, as described
previously.
.RE

.sp
.ne 2
.na
\fB\fBE\fR \fIfile\fR\fR
.ad
.RS 11n
The \fBE\fRdit command is like \fBe\fR, except that the editor does not check
to see if any changes have been made to the buffer since the last \fBw\fR
command.
.RE

.sp
.ne 2
.na
\fB\fBf\fR \fIfile\fR\fR
.ad
.RS 11n
If \fIfile\fR is given, the \fBf\fR command changes the currently remembered
path name to \fIfile\fR. Whether the name is changed or not, the \fBf\fR
command then writes the (possibly new) currently remembered path name to the
standard output in the following format:
.sp
\fB"%s\en"\fR\fIpathname\fR
.sp
The current line number is unchanged.
.RE

.sp
.ne 2
.na
\fB\fB(1,$)g/\fR\fIRE\fR\fB/\fR\fIcommand list\fR\fR
.ad
.RS 26n
In the \fBg\fRlobal command, the first step is to mark every line that matches
the given \fIRE\fR. Then, for every such line, the given \fIcommand list\fR is
executed with the current line (\fB\&.\fR) initially set to that line. When the
\fBg\fR command completes, the current line number has the value assigned by
the last command in the command list. If there were no matching lines, the
current line number is not changed. A single command or the first of a list of
commands appears on the same line as the global command. All lines of a
multi-line list except the last line must be ended with a backslash
(\fB\e\fR\|); \fBa\fR, \fBi\fR, and \fBc\fR commands and associated input are
permitted. The \fB\&.\fR terminating input mode may be omitted if it would be
the last line of the \fIcommand list\fR. An empty \fIcommand list\fR is
equivalent to the \fBp\fR command. The \fBg\fR, \fBG\fR, \fBv\fR, \fBV\fR, and
\fB!\fR commands are \fInot\fR permitted in the \fIcommand list\fR. See also
the NOTES and the last paragraph before FILES below. Any character other than
space or newline can be used instead of a slash to delimit the \fIRE\fR. Within
the \fIRE\fR, the \fIRE\fR delimiter itself can be used as a literal character
if it is preceded by a backslash.
.RE

.sp
.ne 2
.na
\fB\fB(1,$)G/\fR\fIRE\fR\fB/\fR\fR
.ad
.RS 26n
In the interactive \fBG\fRlobal command, the first step is to mark every line
that matches the given \fIRE\fR. Then, for every such line, that line is
written to standard output, the current line (\fB\&.\fR) is changed to that
line, and any \fIone\fR command (other than one of the \fBa\fR, \fBc\fR,
\fBi\fR, \fBg\fR, \fBG\fR, \fBv\fR, and \fBV\fR commands) may be input and is
executed. After the execution of that command, the next marked line is written,
and so on. A new-line acts as a null command. An \fB&\fR causes the
re-execution of the most recent non-null command executed within the current
invocation of \fBG\fR. \fBNote:\fR  The commands input as part of the execution
of the \fBG\fR command may address and affect \fBany\fR lines in the buffer.
The final value of the current line number is the value set by the last command
successfully executed. (Notice that the last command successfully executed is
the \fBG\fR command itself if a command fails or the null command is
specified.) If there were no matching lines, the current line number is not
changed. The \fBG\fR command can be terminated by a \fBSIGINT\fR signal. The
\fBG\fR command can be terminated by an interrupt signal (ASCII DEL or BREAK).
Any character other than space or newline can be used instead of a slash to
delimit the \fIRE\fR. Within the \fIRE\fR, the \fIRE\fR delimiter itself can be
used as a literal character if it is preceded by a backslash.
.RE

.sp
.ne 2
.na
\fB\fBh\fR\fR
.ad
.RS 26n
The \fBhelp\fR command gives a short error message that explains the reason for
the most recent \fB?\fR diagnostic. The current line number is unchanged.
.RE

.sp
.ne 2
.na
\fB\fBH\fR\fR
.ad
.RS 26n
The \fBHelp\fR command causes \fBed\fR to enter a mode in which error messages
are written for all subsequent \fB?\fR diagnostics. It also explains the
previous \fB?\fR if there was one. The \fBH\fR command alternately turns this
mode on and off; it is initially off. The current line number is unchanged.
.RE

.sp
.ne 2
.na
\fB\fB(.,.)i\fR\fR
.ad
.br
.na
\fB<\fItext\fR>\fR
.ad
.br
.na
\fB\fB\&.\fR\fR
.ad
.RS 26n
The \fBinsert\fR command accepts zero or more lines of text and inserts it
before the addressed line in the buffer. The current line (\fB\&.\fR) is left
at the last inserted line, or, if there were none, at the addressed line. This
command differs from the \fBa\fR command only in the placement of the input
text. The maximum number of characters that may be entered from a terminal is
256 per line (including the new-line character).
.sp
.ne 2
.na
\fB\fB/usr/xpg4/bin/ed\fR\fR
.ad
.RS 20n
Address 0 is not legal for this command.
.RE

.sp
.ne 2
.na
\fB\fB/usr/xpg6/bin/ed\fR\fR
.ad
.RS 20n
Address 0 is valid for this command. It is interpreted as if the address 1 were
specified.
.RE

.RE

.sp
.ne 2
.na
\fB\fB(.,.+1)j\fR\fR
.ad
.RS 26n
The \fBj\fRoin command joins contiguous lines by removing the appropriate
new-line characters. If exactly one address is given, this command does
nothing. If lines are joined, the current line number is set to the address of
the joined line. Otherwise, the current line number is unchanged.
.RE

.sp
.ne 2
.na
\fB\fB(.)k\fR\fIx\fR\fR
.ad
.RS 26n
The mar\fBk\fR command marks the addressed line with name \fIx\fR, which must
be an ASCII lower-case letter (\fBa\fR\fB-\fR\fBz\fR). The address \fI a\'x\fR
then addresses this line. The current line (\fB\&.\fR) is unchanged.
.RE

.sp
.ne 2
.na
\fB\fB(.,.)l\fR\fR
.ad
.RS 26n
The \fBl\fR command writes to standard output the addressed lines in a visually
unambiguous form. The characters ( \fB\e\e\fR, \fB\ea\fR, \fB\eb\fR, \fB\ef\fR,
\fB\er\fR, \fB\et\fR, \fB\ev\fR) are written as the corresponding escape
sequence. The \fB\en\fR in that table is not applicable. Non-printable
characters not in the table are written as one three-digit octal number (with a
preceding backslash character) for each byte in the character, with the most
significant byte first.
.sp
Long lines are folded, with the point of folding indicated by writing
backslash/newline character. The length at which folding occurs is unspecified,
but should be appropriate for the output device. The end of each line is marked
with a \fB$\fR. When using the \fB/usr/xpg6/bin/ed\fR command, the end of each
line is marked with a \fB$\fR due to folding, and \fB$\fR characters within the
text are written with a preceding backslash. An \fBl\fR command can be appended
to any other command other than \fBe\fR, \fBE\fR, \fBf\fR, \fBq\fR, \fBQ\fR,
\fBr\fR, \fBw\fR, or \fB!\fR. The current line number is set to the address of
the last line written.
.RE

.sp
.ne 2
.na
\fB\fB(.,.)m\fR\fIa\fR\fR
.ad
.RS 26n
The \fBm\fRove command repositions the addressed line(s) after the line
addressed by \fIa\fR. Address 0 is legal for \fIa\fR and causes the addressed
line(s) to be moved to the beginning of the file. It is an error if address
\fIa\fR falls within the range of moved lines. The current line (\fB\&.\fR) is
left at the last line moved.
.RE

.sp
.ne 2
.na
\fB\fB(.,.)n\fR\fR
.ad
.RS 26n
The \fBn\fRumber command writes the addressed lines, preceding each line by its
line number and a tab character. The current line (\fB\&.\fR) is left at the
last line written. The \fBn\fR command may be appended to any command other
than \fBe\fR, \fBE\fR, \fBf\fR, \fBq\fR, \fBQ\fR, \fBr\fR, \fBw\fR, or \fB!\fR.
.RE

.sp
.ne 2
.na
\fB\fB(.,.)p\fR\fR
.ad
.RS 26n
The \fBp\fRrint command writes the addressed lines to standard output. The
current line (\fB\&.\fR) is left at the last line written. The \fBp\fR command
may be appended to any command other than \fBe\fR, \fBE\fR, \fBf\fR, \fBq\fR,
\fBQ\fR, \fBr\fR, \fBw\fR, or \fB!\fR. For example, \fBdp\fR deletes the
current line and writes the new current line.
.RE

.sp
.ne 2
.na
\fB\fBP\fR\fR
.ad
.RS 26n
The \fBP\fR command causes \fBed\fR to prompt with an asterisk (\fB*\fR) (or
\fIstring\fR, if \fB-p\fR is specified) for all subsequent commands. The
\fBP\fR command alternatively turns this mode on and off; it is initially on if
the \fB-p\fR option is specified, otherwise off. The current line is unchanged.
.RE

.sp
.ne 2
.na
\fB\fBq\fR\fR
.ad
.RS 26n
The \fBq\fRuit command causes \fBed\fR to exit. If the buffer has changed since
the last time the entire buffer was written, the user is warned. See
DIAGNOSTICS.
.RE

.sp
.ne 2
.na
\fB\fBQ\fR\fR
.ad
.RS 26n
The editor exits without checking if changes have been made in the buffer since
the last \fBw\fR command.
.RE

.sp
.ne 2
.na
\fB\fB($)r\fR \fIfile\fR\fR
.ad
.RS 26n
The \fBr\fRead command reads the contents of \fIfile\fR into the buffer. If
\fIfile\fR is not given, the currently remembered file name, if any, is used
(see the \fBe\fR and \fBf\fR commands). The currently remembered file name is
\fBnot\fR changed unless \fIfile\fR is the very first file name mentioned since
\fBed\fR was invoked. Address 0 is legal for \fBr\fR and causes the file to be
read in at the beginning of the buffer. If the read is successful and the
\fB-s\fR option was not specified, the number of characters read is written to
standard output in the following format:
.sp
.in +2
.nf
\fB%d\en\fR, <\fInumber of bytes read\fR>
.fi
.in -2
.sp

The current line (\fB\&.\fR) is set to the last line read. If \fIfile\fR is
replaced by \fB!\fR, the rest of the line is taken to be a shell command (see
\fBsh\fR(1)) whose output is to be read. For example, \fB$r !ls\fR appends the
current directory to the end of the file being edited. Such a shell command is
\fBnot\fR remembered as the current file name.
.RE

.sp
.ne 2
.na
\fB\fB(.,.)s/\fR\fIRE\fR\fB/\fR\fIreplacement\fR\fB/\fR\fR
.ad
.br
.na
\fB\fB(.,.)s/\fR\fIRE\fR\fB/\fR\fIreplacement\fR\fB/\fR\fIcount\fR,
\fIcount\fR=[\fB1-2047\fR]\fR
.ad
.br
.na
\fB\fB(.,.)s/\fR\fIRE\fR\fB/\fR\fIreplacement\fR\fB/g\fR\fR
.ad
.br
.na
\fB\fB(.,.)s/\fR\fIRE\fR\fB/\fR\fIreplacement\fR\fB/l\fR\fR
.ad
.br
.na
\fB\fB(.,.)s/\fR\fIRE\fR\fB/\fR\fIreplacement\fR\fB/n\fR\fR
.ad
.br
.na
\fB\fB(.,.)s/\fR\fIRE\fR\fB/\fR\fIreplacement\fR\fB/p\fR\fR
.ad
.sp .6
.RS 4n
The \fBs\fRubstitute command searches each addressed line for an occurrence of
the specified \fIRE\fR. Zero or more substitution commands can be specified. In
each line in which a match is found, all (non-overlapped) matched strings are
replaced by the \fIreplacement\fR if the global replacement indicator \fBg\fR
appears after the command. If the global indicator does not appear, only the
first occurrence of the matched string is replaced. If a number \fIcount\fR
appears after the command, only the \fIcount\fR-th occurrence of the matched
string on each addressed line is replaced. It is an error if the substitution
fails on \fBall\fR addressed lines. Any character other than space or new-line
may be used instead of the slash (\fB/\fR) to delimit the \fIRE\fR and the
\fIreplacement\fR. The current line (\fB\&.\fR) is left at the last line on
which a substitution occurred. Within the \fIRE\fR, the \fIRE\fR delimiter
itself can be used as a literal character if it is preceded by a backslash. See
also the last paragraph before FILES below.
.sp
An ampersand (\fB&\fR) appearing in the \fIreplacement\fR is replaced by the
string matching the \fIRE\fR on the current line. The special meaning of
\fB&\fR in this context may be suppressed by preceding it by \fB\e\fR\|. As a
more general feature, the characters \fB\e\fR\fIn\fR, where \fIn\fR is a digit,
are replaced by the text matched by the \fIn\fR-th regular subexpression of the
specified \fIRE\fR enclosed between \fB\e(\fR and \fB\e)\fR\&. When nested
parenthesized subexpressions are present, \fIn\fR is determined by counting
occurrences of \fB\e(\fR starting from the left. When the character \fB%\fR is
the only character in the \fIreplacement\fR, the \fIreplacement\fR used in the
most recent substitute command is used as the \fIreplacement\fR in the current
substitute command. If there was no previous substitute command, the use of
\fB%\fR in this manner is an error. The \fB%\fR loses its special meaning when
it is in a replacement string of more than one character or is preceded by a
\fB\e\fR\|. For each backslash (\e) encountered in scanning \fIreplacement\fR
from beginning to end, the following character loses its special meaning (if
any). It is unspecified what special meaning is given to any character other
than \fB&\fR, \fB\e\fR, \fB%\fR, or digits.
.sp
A line may be split by substituting a new-line character into it. The new-line
in the \fIreplacement\fR must be escaped by preceding it by \fB\e\fR\&. Such
substitution cannot be done as part of a \fBg\fR or \fBv\fR command list. The
current line number is set to the address of the last line on which a
substitution is performed. If no substitution is performed, the current line
number is unchanged. If a line is split, a substitution is considered to have
been performed on each of the new lines for the purpose of determining the new
current line number. A substitution is considered to have been performed even
if the replacement string is identical to the string that it replaces.
.sp
The substitute command supports the following indicators:
.sp
.ne 2
.na
\fB\fIcount\fR\fR
.ad
.RS 9n
Substitute for the \fIcount\fRth occurrence only of the \fIRE\fR found on each
addressed line. \fIcount\fR must be between \fB1\fR-\fB2047\fR.
.RE

.sp
.ne 2
.na
\fB\fBg\fR\fR
.ad
.RS 9n
Globally substitute for all non-overlapping instances of the \fIRE\fR rather
than just the first one. If both \fBg\fR and \fIcount\fR are specified, the
results are unspecified.
.RE

.sp
.ne 2
.na
\fB\fBl\fR\fR
.ad
.RS 9n
Write to standard output the final line in which a substitution was made. The
line is written in the format specified for the \fBl\fR command.
.RE

.sp
.ne 2
.na
\fB\fBn\fR\fR
.ad
.RS 9n
Write to standard output the final line in which a substitution was made. The
line is written in the format specified for the \fBn\fR command.
.RE

.sp
.ne 2
.na
\fB\fBp\fR\fR
.ad
.RS 9n
Write to standard output the final line in which a substitution was made. The
line will be written in the format specified for the \fBp\fR command.
.RE

.RE

.sp
.ne 2
.na
\fB\fB(.,.)t\fR\fIa\fR\fR
.ad
.sp .6
.RS 4n
This command acts just like the \fBm\fR command, except that a \fIcopy\fR of
the addressed lines is placed after address \fBa\fR (which may be 0). The
current line (\fB\&.\fR) is left at the last line copied.
.RE

.sp
.ne 2
.na
\fB\fBu\fR\fR
.ad
.sp .6
.RS 4n
The \fBu\fRndo command nullifies the effect of the most recent command that
modified anything in the buffer, namely the most recent \fBa\fR, \fBc\fR,
\fBd\fR, \fBg\fR, \fBi\fR, \fBj\fR, \fBm\fR, \fBr\fR, \fBs\fR, \fBt\fR,
\fBu\fR, \fBv\fR, \fBG\fR, or \fBV\fR command. All changes made to the buffer
by a \fBg\fR, \fBG\fR, \fBv\fR, or \fBV\fR global command is undone as a single
change.If no changes were made by the global command (such as with \fBg/\fR
\fIRE\fR\fB/p\fR), the \fBu\fR command has no effect. The current line number
is set to the value it had  immediately before the  command being undone
started.
.RE

.sp
.ne 2
.na
\fB\fB(1,$)v/\fR\fIRE\fR\fB/\fR\fIcommand list\fR\fR
.ad
.sp .6
.RS 4n
This command is the same as the global command \fBg\fR, except that the lines
marked during the first step are those that do \fBnot\fR match the \fIRE\fR.
.RE

.sp
.ne 2
.na
\fB\fB(1,$)V/\fR\fIRE\fR\fB/\fR\fR
.ad
.sp .6
.RS 4n
This command is the same as the interactive global command \fBG\fR, except that
the lines that are marked during the first step are those that do \fBnot\fR
match the \fIRE\fR.
.RE

.sp
.ne 2
.na
\fB\fB(1,$)w\fR \fIfile\fR\fR
.ad
.sp .6
.RS 4n
The \fBw\fRrite command writes the addressed lines into \fIfile\fR. If
\fIfile\fR does not exist, it is created with mode \fB666\fR (readable and
writable by everyone), unless your file creation mask dictates otherwise. See
the description of the \fBumask\fR special command on \fBsh\fR(1). The
currently remembered file name is \fBnot\fR changed unless \fIfile\fR is the
very first file name mentioned since \fBed\fR was invoked. If no file name is
given, the currently remembered file name, if any, is used (see the \fBe\fR and
\fBf\fR commands). The current line (\fB\&.\fR) is unchanged. If the command is
successful, the number of characters written is printed, unless the \fB-s\fR
option is specified in the following format:
.sp
.in +2
.nf
\fB"%d\en",\fR<\fInumber of bytes written\fR>
.fi
.in -2
.sp

If \fIfile\fR is replaced by \fB!\fR, the rest of the line is taken to be a
shell (see \fBsh\fR(1)) command whose standard input is the addressed lines.
Such a shell command is \fInot\fR remembered as the current path name. This
usage of the write command with \fB!\fR is to be considered as a ``last \fBw\fR
command that wrote the entire buffer''.
.RE

.sp
.ne 2
.na
\fB\fB(1,$)W\fR \fIfile\fR\fR
.ad
.RS 19n
This command is the same as the \fBw\fRrite command above, except that it
appends the addressed lines to the end of \fIfile\fR if it exists. If
\fIfile\fR does not exist, it is created as described above for the \fBw\fR
command.
.RE

.sp
.ne 2
.na
\fB\fBX\fR\fR
.ad
.RS 19n
An educated guess is made to determine whether text read for the \fBe\fR and
\fBr\fR commands is encrypted. A null key turns off encryption. Subsequent
\fBe\fR, \fBr\fR, and \fBw\fR commands will use this key to encrypt or decrypt
the text. An explicitly empty key turns off encryption. Also, see the \fB-x\fR
option of \fBed\fR.
.RE

.sp
.ne 2
.na
\fB\fB($)=\fR\fR
.ad
.RS 19n
The line number of the addressed line is written to standard output in the
following format:
.sp
.in +2
.nf
\fB"%d\en"\fR<\fIline number\fR>
.fi
.in -2
.sp

The current line number is unchanged by this command.
.RE

.sp
.ne 2
.na
\fB\fB!\fR\fIshell command\fR\fR
.ad
.RS 19n
The remainder of the line after the \fB!\fR is sent to the UNIX system shell
(see \fBsh\fR(1)) to be interpreted as a command. Within the text of that
command, the unescaped character \fB%\fR is replaced with the remembered file
name. If a \fB!\fR appears as the first character of the shell command, it is
replaced with the text of the previous shell command. Thus, \fB!!\fR repeats
the last shell command. If any replacements of \fB%\fR or \fB!\fR are
performed, the modified line is written to the standard output before
\fIcommand\fR is executed. The \fB!\fR command will write:
.sp
\fB"!\en"\fR
.sp
to standard output upon completion, unless the \fB-s\fR option is specified.
The current line number is unchanged.
.RE

.sp
.ne 2
.na
\fB\fB(.+1)\fR<new-line>\fR
.ad
.RS 19n
An address alone on a line causes the addressed line to be written. A new-line
alone is equivalent to \fB\&.+1p\fR. It is useful for stepping forward through
the buffer. The current line number will be set to the address of the written
line.
.RE

.sp
.LP
If an interrupt signal (ASCII DEL or BREAK) is sent, \fBed\fR writes a
"\fB?\en\fR" and returns to \fBits\fR command level.
.sp
.LP
The \fBed\fR utility takes the standard action for all signals with the
following exceptions:
.sp
.ne 2
.na
\fB\fBSIGINT\fR\fR
.ad
.RS 10n
The \fBed\fR utility interrupts its current activity, writes the string
"\fB?\en\fR" to standard output, and returns to command mode.
.RE

.sp
.ne 2
.na
\fB\fBSIGHUP\fR\fR
.ad
.RS 10n
If the buffer is not empty and has changed since the last write, the \fBed\fR
utility attempts to write a copy of the buffer in a file. First, the file named
\fBed.hup\fR in the current directory is used. If that fails, the file named
\fBed.hup\fR in the directory named by the \fBHOME\fR environment variable is
used. In any case, the \fBed\fR utility exits without returning to command
mode.
.RE

.sp
.LP
Some size limitations are in effect: 512 characters in a line, 256 characters
in a global command list, and 255 characters in the path name of a file
(counting slashes). The limit on the number of lines depends on the amount of
user memory. Each line takes 1 word.
.sp
.LP
When reading a file, \fBed\fR discards \fBASCII\fR and \fBNUL\fR characters.
.sp
.LP
If a file is not terminated by a new-line character, \fBed\fR adds one and puts
out a message explaining what it did.
.sp
.LP
If the closing delimiter of an \fBRE\fR or of a replacement string (for
example, \fB/\fR) would be the last character before a new-line, that delimiter
may be omitted, in which case the addressed line is written. The following
pairs of commands are equivalent:
.sp
.ne 2
.na
\fB\fBs/s1/s2\fR\fR
.ad
.RS 11n
\fBs/s1/s2/p\fR
.RE

.sp
.ne 2
.na
\fB\fBg/s1\fR\fR
.ad
.RS 11n
\fBg/s1/p\fR
.RE

.sp
.ne 2
.na
\fB\fB?s1\fR\fR
.ad
.RS 11n
\fB?s1?\fR
.RE

.sp
.LP
If an invalid command is entered, \fBed\fR writes the string:
.sp
.LP
\fB"?\en"\fR
.sp
.LP
(followed by an explanatory message if \fIhelp mode\fR has been enabled by the
\fBH\fR command) to standard output and continues in command mode with the
current line number unchanged.
.SH OPTIONS
.sp
.ne 2
.na
\fB\fB-C\fR\fR
.ad
.RS 13n
Encryption option. The same as the \fB-x\fR option, except that \fBed\fR
simulates a \fBC\fR command. The \fBC\fR command is like the \fBX\fR command,
except that all text read in is assumed to have been encrypted.
.RE

.sp
.ne 2
.na
\fB\fB\fR\fB-p\fR\fIstring\fR \fR
.ad
.RS 13n
Allows the user to specify a prompt string. By default, there is no prompt
string.
.RE

.sp
.ne 2
.na
\fB\fB-s\fR |  \fB-;\fR\fR
.ad
.RS 13n
Suppresses the writing of character counts by \fBe\fR, \fBr\fR, and \fBw\fR
commands, of diagnostics from \fBe\fR and \fBq\fR commands, and of the \fB!\fR
prompt after a \fB!\fR\fIshell command\fR.
.RE

.sp
.ne 2
.na
\fB\fB-x\fR\fR
.ad
.RS 13n
Encryption option. When \fB-x\fR is used, \fBed\fR simulates an \fBX\fR command
and prompts the user for a key. The \fBX\fR command makes an educated guess to
determine whether text read in is encrypted or not. The temporary buffer file
is encrypted also, using a transformed version of the key typed in for the
\fB-x\fR option. See NOTES.
.RE

.SH OPERANDS
.sp
.LP
The following operand is supported:
.sp
.ne 2
.na
\fB\fIfile\fR\fR
.ad
.RS 8n
If \fIfile\fR is specified, \fBed\fR simulates an \fBe\fR command on the file
named by the path name \fIfile\fR before accepting commands from the standard
input.
.RE

.SH USAGE
.sp
.LP
See \fBlargefile\fR(7) for the description of the behavior of \fBed\fR and
\fBred\fR when encountering files greater than or equal to 2 Gbyte ( 2^31
bytes).
.SH ENVIRONMENT VARIABLES
.sp
.LP
See \fBenviron\fR(7) for descriptions of the following environment variables
that affect the execution of \fBed\fR: \fBHOME\fR, \fBLANG\fR, \fBLC_ALL\fR,
\fBLC_CTYPE\fR, \fBLC_COLLATE\fR, \fBLC_MESSAGES\fR, and \fBNLSPATH\fR.
.SH EXIT STATUS
.sp
.LP
The following exit values are returned:
.sp
.ne 2
.na
\fB\fB0\fR\fR
.ad
.RS 6n
Successful completion without any file or command errors.
.RE

.sp
.ne 2
.na
\fB\fB>0\fR\fR
.ad
.RS 6n
An error occurred.
.RE

.SH FILES
.sp
.ne 2
.na
\fB\fB$TMPDIR\fR\fR
.ad
.RS 12n
If this environment variable is not \fINULL\fR, its value is used in place of
\fB/var/tmp\fR as the directory name for the temporary work file.
.RE

.sp
.ne 2
.na
\fB\fB/var/tmp\fR\fR
.ad
.RS 12n
If \fB/var/tmp\fR exists, it is used as the directory name for the temporary
work file.
.RE

.sp
.ne 2
.na
\fB\fB/tmp\fR\fR
.ad
.RS 12n
If the environment variable \fBTMPDIR\fR does not exist or is \fINULL,\fR and
if \fB/var/tmp\fR does not exist, then \fB/tmp\fR is used as the directory name
for the temporary work file.
.RE

.sp
.ne 2
.na
\fB\fBed.hup\fR\fR
.ad
.RS 12n
Work is saved here if the terminal is hung up.
.RE

.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(7) for descriptions of the following attributes:
.SS "/usr/bin/ed, /usr/bin/red"
.sp

.sp
.TS
box;
c | c
l | l .
ATTRIBUTE TYPE	ATTRIBUTE VALUE
_
CSI	Enabled
.TE

.SS "/usr/xpg4/bin/ed"
.sp

.sp
.TS
box;
c | c
l | l .
ATTRIBUTE TYPE	ATTRIBUTE VALUE
_
CSI	Enabled
_
Interface Stability	Standard
.TE

.SS "/usr/xpg6/bin/ed"
.sp

.sp
.TS
box;
c | c
l | l .
ATTRIBUTE TYPE	ATTRIBUTE VALUE
_
CSI	Enabled
_
Interface Stability	Standard
.TE

.SH SEE ALSO
.sp
.LP
.BR edit (1),
.BR ex (1),
.BR grep (1),
.BR ksh (1),
.BR sed (1),
.BR sh (1),
.BR stty (1),
.BR umask (1),
.BR vi (1),
.BR fspec (5),
.BR attributes (7),
.BR environ (7),
.BR largefile (7),
.BR regex (7),
.BR standards (7)
.SH DIAGNOSTICS
.sp
.ne 2
.na
\fB\fB?\fR\fR
.ad
.RS 9n
for command errors.
.RE

.sp
.ne 2
.na
\fB\fB?\fR\fIfile\fR\fR
.ad
.RS 9n
for an inaccessible file. Use the \fBh\fRelp and \fBH\fRelp commands for
detailed explanations.
.RE

.sp
.LP
If changes have been made in the buffer since the last \fBw\fR command that
wrote the entire buffer, \fBed\fR warns the user if an attempt is made to
destroy \fBed\fR's buffer via the \fBe\fR or \fBq\fR commands. It writes
\fB?\fR and allows one to continue editing. A second \fBe\fR or \fBq\fR command
at this point will take effect. The \fB-s\fR command-line option inhibits this
feature.
.SH NOTES
.sp
.LP
The \fB-\fR option, although it continues to be supported, has been replaced in
the documentation by the \fB-s\fR option that follows the \fBCommand Syntax
Standard\fR (see \fBIntro\fR(1)).
.sp
.LP
A \fB!\fR command cannot be subject to a \fBg\fR or a \fBv\fR command.
.sp
.LP
The \fB!\fR command and the \fB!\fR escape from the \fBe\fR, \fBr\fR, and
\fBw\fR commands cannot be used if the editor is invoked from a restricted
shell (see \fBsh\fR(1)).
.sp
.LP
The sequence \fB\en\fR in an \fBRE\fR does not match a new-line character.
.sp
.LP
If the editor input is coming from a command file (for example, \fBed\fR
\fIfile\fR \fB<\fR \fIed_cmd_file\fR), the editor exits at the first failure.
.sp
.LP
Loading an alternate \fBmalloc()\fR library using the environment variable
\fBLD_PRELOAD\fR can cause problems for \fB/usr/bin/ed\fR.