ed: port to otools

15 files changed, 3982 insertions, 0 deletions

diff --git a/bin/ed/CVS/Entries b/bin/ed/CVS/Entries
new file mode 100644
index 0000000..fa6d8e5
--- /dev/null
+++ b/bin/ed/CVS/Entries
@@ -0,0 +1,14 @@
+D/USD.doc////
+D/test////
+/Makefile/1.12/Wed Jul 14 12:55:12 2021//
+/POSIX/1.8/Wed Jul 14 12:55:12 2021//
+/README/1.5/Wed Jul 14 12:55:12 2021//
+/buf.c/1.24/Wed Jul 14 12:55:12 2021//
+/ed.1/1.76/Wed Jul 14 12:55:24 2021//
+/ed.h/1.22/Wed Jul 14 12:55:12 2021//
+/glbl.c/1.20/Wed Jul 14 12:55:12 2021//
+/io.c/1.24/Wed Jul 14 12:55:12 2021//
+/main.c/1.66/Wed Jul 14 12:55:12 2021//
+/re.c/1.19/Wed Jul 14 12:55:12 2021//
+/sub.c/1.18/Wed Jul 14 12:55:12 2021//
+/undo.c/1.14/Wed Jul 14 12:55:12 2021//
diff --git a/bin/ed/CVS/Repository b/bin/ed/CVS/Repository
new file mode 100644
index 0000000..6ee887f
--- /dev/null
+++ b/bin/ed/CVS/Repository
@@ -0,0 +1 @@
+src/bin/ed
diff --git a/bin/ed/CVS/Root b/bin/ed/CVS/Root
new file mode 100644
index 0000000..3811072
--- /dev/null
+++ b/bin/ed/CVS/Root
@@ -0,0 +1 @@
+/cvs
diff --git a/bin/ed/Makefile b/bin/ed/Makefile
new file mode 100644
index 0000000..bf60cf2
--- /dev/null
+++ b/bin/ed/Makefile
@@ -0,0 +1,6 @@
+#	$OpenBSD: Makefile,v 1.12 2018/06/15 08:46:24 martijn Exp $
+
+PROG=	ed
+SRCS=	 buf.c glbl.c io.c main.c re.c sub.c undo.c
+
+.include <bsd.prog.mk>
diff --git a/bin/ed/POSIX b/bin/ed/POSIX
new file mode 100644
index 0000000..1cd2afc
--- /dev/null
+++ b/bin/ed/POSIX
@@ -0,0 +1,91 @@
+$OpenBSD: POSIX,v 1.8 2014/05/24 01:35:55 daniel Exp $
+$NetBSD: POSIX,v 1.9 1995/03/21 09:04:32 cgd Exp $
+
+This version of ed(1) is not strictly POSIX compliant, as described in
+the POSIX 1003.2 document.  The following is a summary of the omissions,
+extensions and possible deviations from POSIX 1003.2.
+
+OMISSIONS
+---------
+1) Locale(3) is not supported yet.
+
+2) For backwards compatibility, the POSIX rule that says a range of
+   addresses cannot be used where only a single address is expected has
+   been relaxed.
+
+3) To support the BSD `s' command (see extension [1] below),
+   substitution patterns cannot be delimited by numbers or the characters
+   `r', `g' and `p'.  In contrast, POSIX specifies any character except
+   space or newline can be used as a delimiter.
+
+EXTENSIONS
+----------
+1) BSD commands have been implemented wherever they do not conflict with
+   the POSIX standard.  The BSD-ism's included are:
+	i) `s' (i.e., s[n][rgp]*) to repeat a previous substitution,
+	ii) `W' for appending text to an existing file,
+	iii) `wq' for exiting after a write,
+	iv) `z' for scrolling through the buffer, and
+	v) BSD line addressing syntax (i.e., `^' and `%') is recognized.
+
+2) The POSIX interactive global commands `G' and `V' are extended to
+   support multiple commands, including `a', `i' and `c'.  The command
+   format is the same as for the global commands `g' and `v', i.e., one
+   command per line with each line, except for the last, ending in a
+   backslash (\).
+
+3) An extension to the POSIX file commands `E', `e', `r', `W' and `w' is
+   that <file> arguments are processed for backslash escapes, i.e.,  any
+   character preceded by a backslash is interpreted literally.  If the
+   first unescaped character of a <file> argument is a bang (!), then the
+   rest of the line is interpreted as a shell command, and no escape
+   processing is performed by ed.
+
+DEVIATIONS
+----------
+1) Though ed is not a stream editor, it can be used to edit binary files.
+   To assist in binary editing, when a file containing at least one ASCII
+   NUL character is written, a newline is not appended if it did not
+   already contain one upon reading.  In particular, reading /dev/null
+   prior to writing prevents appending a newline to a binary file.
+
+   For example, to create a file with ed containing a single NUL character:
+      $ ed file
+      a
+      ^@
+      .
+      r /dev/null
+      wq
+
+    Similarly, to remove a newline from the end of binary `file':
+      $ ed file
+      r /dev/null
+      wq
+
+2) Since the behavior of `u' (undo) within a `g' (global) command list is
+   not specified by POSIX, it follows the behavior of the SunOS ed:
+   undo forces a global command list to be executed only once, rather than
+   for each line matching a global pattern.  In addition, each instance of
+   `u' within a global command undoes all previous commands (including
+   undo's) in the command list.  This seems the best way, since the
+   alternatives are either too complicated to implement or too confusing
+   to use.
+
+   The global/undo combination is useful for masking errors that
+   would otherwise cause a script to fail.  For instance, an ed script
+   to remove any occurrences of either `censor1' or `censor2' might be
+   written as:
+   	ed - file <<EOF
+	1g/.*/u\
+	,s/censor1//g\
+	,s/censor2//g
+	...
+
+3) The `m' (move) command within a `g' command list also follows the SunOS
+   ed implementation: any moved lines are removed from the global command's
+   `active' list.
+
+4) If ed is invoked with a name argument prefixed by a bang (!), then the
+   remainder of the argument is interpreted as a shell command.  To invoke
+   ed on a file whose name starts with bang, prefix the name with a
+   backslash.
diff --git a/bin/ed/README b/bin/ed/README
new file mode 100644
index 0000000..4405e45
--- /dev/null
+++ b/bin/ed/README
@@ -0,0 +1,19 @@
+$OpenBSD: README,v 1.5 2018/06/15 08:46:24 martijn Exp $
+$NetBSD: README,v 1.9 1995/03/21 09:04:33 cgd Exp $
+
+ed is an 8-bit-clean, POSIX-compliant line editor.  It should work with
+any regular expression package that conforms to the POSIX interface
+standard, such as GNU regex(3).
+
+If reliable signals are supported (e.g., POSIX sigaction(2)), it should
+compile with little trouble.  Otherwise, the macros SPL1() and SPL0()
+should be redefined to disable interrupts.
+
+The file `POSIX' describes extensions to and deviations from the POSIX
+standard.
+
+The ./test directory contains regression tests for ed. The README
+file in that directory explains how to run these.
+
+For a description of the ed algorithm, see Kernighan and Plauger's book
+"Software Tools in Pascal," Addison-Wesley, 1981.
diff --git a/bin/ed/buf.c b/bin/ed/buf.c
new file mode 100644
index 0000000..06dc7eb
--- /dev/null
+++ b/bin/ed/buf.c
@@ -0,0 +1,289 @@
+/*	$OpenBSD: buf.c,v 1.24 2019/06/28 13:34:59 deraadt Exp $	*/
+/*	$NetBSD: buf.c,v 1.15 1995/04/23 10:07:28 cgd Exp $	*/
+
+/* buf.c: This file contains the scratch-file buffer routines for the
+   ed line editor. */
+/*-
+ * Copyright (c) 1993 Andrew Moore, Talke Studio.
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <limits.h>
+#include <regex.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "ed.h"
+
+
+static FILE *sfp;			/* scratch file pointer */
+static off_t sfseek;			/* scratch file position */
+static int seek_write;			/* seek before writing */
+static line_t buffer_head;		/* incore buffer */
+
+/* get_sbuf_line: get a line of text from the scratch file; return pointer
+   to the text */
+char *
+get_sbuf_line(line_t *lp)
+{
+	static char *sfbuf = NULL;	/* buffer */
+	static int sfbufsz = 0;		/* buffer size */
+	int len;
+
+	if (lp == &buffer_head)
+		return NULL;
+	seek_write = 1;				/* force seek on write */
+	/* out of position */
+	if (sfseek != lp->seek) {
+		sfseek = lp->seek;
+		if (fseeko(sfp, sfseek, SEEK_SET) == -1) {
+			perror(NULL);
+			seterrmsg("cannot seek temp file");
+			return NULL;
+		}
+	}
+	len = lp->len;
+	REALLOC(sfbuf, sfbufsz, len + 1, NULL);
+	if (fread(sfbuf, sizeof(char), len, sfp) != len) {
+		perror(NULL);
+		seterrmsg("cannot read temp file");
+		return NULL;
+	}
+	sfseek += len;				/* update file position */
+	sfbuf[len] = '\0';
+	return sfbuf;
+}
+
+
+/* put_sbuf_line: write a line of text to the scratch file and add a line node
+   to the editor buffer;  return a pointer to the end of the text */
+char *
+put_sbuf_line(char *cs)
+{
+	line_t *lp;
+	int len;
+	char *s;
+
+	if ((lp = malloc(sizeof(line_t))) == NULL) {
+		perror(NULL);
+		seterrmsg("out of memory");
+		return NULL;
+	}
+	/* assert: cs is '\n' terminated */
+	for (s = cs; *s != '\n'; s++)
+		;
+	if (s - cs >= LINECHARS) {
+		seterrmsg("line too long");
+		free(lp);
+		return NULL;
+	}
+	len = s - cs;
+	/* out of position */
+	if (seek_write) {
+		if (fseek(sfp, 0L, SEEK_END) == -1) {
+			perror(NULL);
+			seterrmsg("cannot seek temp file");
+			free(lp);
+			return NULL;
+		}
+		sfseek = ftello(sfp);
+		seek_write = 0;
+	}
+	/* assert: SPL1() */
+	if (fwrite(cs, sizeof(char), len, sfp) != len) {
+		sfseek = -1;
+		perror(NULL);
+		seterrmsg("cannot write temp file");
+		free(lp);
+		return NULL;
+	}
+	lp->len = len;
+	lp->seek  = sfseek;
+	add_line_node(lp);
+	sfseek += len;			/* update file position */
+	return ++s;
+}
+
+
+/* add_line_node: add a line node in the editor buffer after the current line */
+void
+add_line_node(line_t *lp)
+{
+	line_t *cp;
+
+	/* this get_addressed_line_node last! */
+	cp = get_addressed_line_node(current_addr);
+	INSQUE(lp, cp);
+	addr_last++;
+	current_addr++;
+}
+
+
+/* get_line_node_addr: return line number of pointer */
+int
+get_line_node_addr(line_t *lp)
+{
+	line_t *cp = &buffer_head;
+	int n = 0;
+
+	while (cp != lp && (cp = cp->q_forw) != &buffer_head)
+		n++;
+	if (n && cp == &buffer_head) {
+		seterrmsg("invalid address");
+		return ERR;
+	 }
+	 return n;
+}
+
+
+/* get_addressed_line_node: return pointer to a line node in the editor buffer */
+line_t *
+get_addressed_line_node(int n)
+{
+	static line_t *lp = &buffer_head;
+	static int on = 0;
+
+	SPL1();
+	if (n > on) {
+		if (n <= (on + addr_last) >> 1)
+			for (; on < n; on++)
+				lp = lp->q_forw;
+		else {
+			lp = buffer_head.q_back;
+			for (on = addr_last; on > n; on--)
+				lp = lp->q_back;
+		}
+	} else {
+		if (n >= on >> 1)
+			for (; on > n; on--)
+				lp = lp->q_back;
+		else {
+			lp = &buffer_head;
+			for (on = 0; on < n; on++)
+				lp = lp->q_forw;
+		}
+	}
+	SPL0();
+	return lp;
+}
+
+
+extern int newline_added;
+
+#define SCRATCH_TEMPLATE      "/tmp/ed.XXXXXXXXXX"
+static char sfn[sizeof(SCRATCH_TEMPLATE)+1] = "";	/* scratch file name */
+
+/* open_sbuf: open scratch file */
+int
+open_sbuf(void)
+{
+	int fd = -1;
+
+	isbinary = newline_added = 0;
+	strlcpy(sfn, SCRATCH_TEMPLATE, sizeof sfn);
+	if ((fd = mkstemp(sfn)) == -1 ||
+	    (sfp = fdopen(fd, "w+")) == NULL) {
+		if (fd != -1)
+			close(fd);
+		perror(sfn);
+		seterrmsg("cannot open temp file");
+		return ERR;
+	}
+	return 0;
+}
+
+
+/* close_sbuf: close scratch file */
+int
+close_sbuf(void)
+{
+	if (sfp) {
+		if (fclose(sfp) == EOF) {
+			perror(sfn);
+			seterrmsg("cannot close temp file");
+			return ERR;
+		}
+		sfp = NULL;
+		unlink(sfn);
+	}
+	sfseek = seek_write = 0;
+	return 0;
+}
+
+
+/* quit: remove_lines scratch file and exit */
+void
+quit(int n)
+{
+	if (sfp) {
+		fclose(sfp);
+		unlink(sfn);
+	}
+	exit(n);
+}
+
+
+static unsigned char ctab[256];		/* character translation table */
+
+/* init_buffers: open scratch buffer; initialize line queue */
+void
+init_buffers(void)
+{
+	int i = 0;
+
+	/* Read stdin one character at a time to avoid i/o contention
+	   with shell escapes invoked by nonterminal input, e.g.,
+	   ed - <<EOF
+	   !cat
+	   hello, world
+	   EOF */
+	setvbuf(stdin, NULL, _IONBF, 0);
+	if (open_sbuf() < 0)
+		quit(2);
+	REQUE(&buffer_head, &buffer_head);
+	for (i = 0; i < 256; i++)
+		ctab[i] = i;
+}
+
+
+/* translit_text: translate characters in a string */
+char *
+translit_text(char *s, int len, int from, int to)
+{
+	static int i = 0;
+
+	unsigned char *us;
+
+	ctab[i] = i;			/* restore table to initial state */
+	ctab[i = from] = to;
+	for (us = (unsigned char *) s; len-- > 0; us++)
+		*us = ctab[*us];
+	return s;
+}
diff --git a/bin/ed/ed.1 b/bin/ed/ed.1
new file mode 100644
index 0000000..f5fc5be
--- /dev/null
+++ b/bin/ed/ed.1
@@ -0,0 +1,859 @@
+.\"	$OpenBSD: ed.1,v 1.76 2021/03/08 02:47:26 jsg Exp $
+.\"
+.\" Copyright (c) 1993 Andrew Moore, Talke Studio.
+.\" 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.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+.\"
+.Dd $Mdocdate: March 8 2021 $
+.Dt ED 1
+.Os
+.Sh NAME
+.Nm ed
+.Nd text editor
+.Sh SYNOPSIS
+.Nm ed
+.Op Fl
+.Op Fl s
+.Op Fl p Ar string
+.Op Ar file
+.Sh DESCRIPTION
+.Nm
+is a line-oriented text editor.
+It is used to create, display, modify, and otherwise manipulate text files.
+If invoked with a
+.Ar file
+argument, then a copy of
+.Ar file
+is read into the editor's buffer.
+Changes are made to this copy and not directly to
+.Ar file
+itself.
+Upon quitting
+.Nm ed ,
+any changes not explicitly saved with a
+.Ic w
+command are lost.
+.Pp
+Editing is done in two distinct modes:
+.Em command
+and
+.Em input .
+When first invoked,
+.Nm
+is in command mode.
+In this mode, commands are read from the standard input and
+executed to manipulate the contents of the editor buffer.
+.Pp
+A typical command might look like:
+.Pp
+.Dl ,s/old/new/g
+.Pp
+which replaces all occurrences of the string
+.Qq old
+with
+.Qq new .
+.Pp
+When an input command, such as
+.Ic a
+.Pq append ,
+.Ic i
+.Pq insert ,
+or
+.Ic c
+.Pq change
+is given,
+.Nm
+enters input mode.
+This is the primary means of adding text to a file.
+In this mode, no commands are available;
+instead, the standard input is written directly to the editor buffer.
+Lines consist of text up to and including a newline character.
+Input mode is terminated by entering a single period
+.Pq Ql \&.
+on a line.
+.Pp
+All
+.Nm
+commands operate on whole lines or ranges of lines; e.g.,
+the
+.Ic d
+command deletes lines; the
+.Ic m
+command moves lines, and so on.
+It is possible to modify only a portion of a line by means of replacement,
+as in the example above.
+However, even here, the
+.Ic s
+command is applied to whole lines at a time.
+.Pp
+In general,
+.Nm
+commands consist of zero or more line addresses, followed by a single
+character command and possibly additional parameters; i.e.,
+commands have the structure:
+.Pp
+.Sm off
+.D1 Oo Ar address Oo , Ar address Oc Oc Ar command Op Ar parameters
+.Sm on
+.Pp
+The address(es) indicate the line or range of lines to be affected by the
+command.
+If fewer addresses are given than the command accepts, then
+default addresses are supplied.
+.Pp
+Many
+.Nm
+commands and line addresses support basic regular expressions
+.Pq BREs .
+See
+.Xr re_format 7
+for more information on regular expressions.
+.Pp
+The options are as follows:
+.Bl -tag -width "-p string"
+.It Fl
+Same as the
+.Fl s
+option
+.Pq deprecated .
+.It Fl p Ar string
+Specifies a command prompt.
+This may be toggled on and off with the
+.Ic P
+command.
+.It Fl s
+Suppress diagnostics.
+This should be used if
+.Nm
+standard input is from a script.
+.It Ar file
+Specifies the name of a file to read.
+If
+.Ar file
+is prefixed with a
+bang
+.Pq Ql \&! ,
+then it is interpreted as a shell command.
+In this case, what is read is the standard output of
+.Ar file
+executed via
+.Xr sh 1 .
+To read a file whose name begins with a bang, prefix the
+name with a backslash
+.Pq Ql \e .
+The default filename is set to
+.Ar file
+only if it is not prefixed with a bang.
+.El
+.Ss LINE ADDRESSING
+An address represents the number of a line in the buffer.
+.Nm
+maintains a
+.Em current address
+which is typically supplied to commands as the default address
+when none is specified.
+When a file is first read, the current address is set to the last line
+of the file.
+In general, the current address is set to the last line affected by a command.
+.Pp
+A line address is
+constructed from one of the bases in the list below, optionally followed
+by a numeric offset.
+The offset may include any combination of digits, operators (e.g.,
+.Ql + ,
+.Ql - ,
+and
+.Ql ^ ) ,
+and whitespace.
+Addresses are read from left to right, and their values are computed
+relative to the current address.
+.Pp
+One exception to the rule that addresses represent line numbers is the
+address
+.Ad 0
+.Pq zero .
+This means
+.Dq before the first line ,
+and is legal wherever it makes sense.
+.Pp
+An address range is two addresses separated either by a comma or semi-colon.
+The value of the first address in a range cannot exceed the
+value of the second.
+If only one address is given in a range,
+then the second address is set to the given address.
+If an
+.Ar n Ns -tuple
+of addresses is given where
+.Ar n
+\*(Gt 2,
+then the corresponding range is determined by the last two addresses in the
+.Ar n Ns -tuple .
+If only one address is expected, then the last address is used.
+.Pp
+Each address in a comma-delimited range is interpreted relative to the
+current address.
+In a semi-colon-delimited range, the first address is
+used to set the current address, and the second address is interpreted
+relative to the first.
+.Pp
+The following address symbols are recognized:
+.Bl -tag -width Ds
+.It \&.
+The current line
+.Pq address
+in the buffer.
+.It $
+The last line in the buffer.
+.It Ar n
+The
+.Ar n Ns th
+line in the buffer, where
+.Ar n
+is a number in the range
+.Ad [0,$] .
+.It - or ^
+The previous line.
+This is equivalent to
+.Ad \-1
+and may be repeated with cumulative effect.
+.It Xo
+.Pf - Ar n No or\ \&
+.Pf ^ Ar n
+.Xc
+The
+.Ar n Ns th
+previous line, where
+.Ar n
+is a non-negative number.
+.It +
+The next line.
+This is equivalent to
+.Ad +1
+and may be repeated with cumulative effect.
+.It + Ns Ar n
+The
+.Ar n Ns th
+next line, where
+.Ar n
+is a non-negative number.
+.It \&, or %
+The first through last lines in the buffer.
+This is equivalent to the address range
+.Ad 1,$ .
+.It \&;
+The current through last lines in the buffer.
+This is equivalent to the address range
+.Ad .,$ .
+.It / Ns Ar re Ns /
+The next line containing the regular expression
+.Ar re .
+The search wraps to the beginning of the buffer and continues down to the
+current line, if necessary.
+The second slash can be omitted if it ends a line.
+.Qq //
+repeats the last search.
+.It Pf ? Ar re ?
+The previous line containing the regular expression
+.Ar re .
+The search wraps to the end of the buffer and continues up to the
+current line, if necessary.
+The second question mark can be omitted if it ends a line.
+.Qq ??
+repeats the last search.
+.It \&' Ns Ar lc
+The line previously marked by a
+.Ic k
+.Pq mark
+command, where
+.Ar lc
+is a lower case letter.
+.El
+.Ss COMMANDS
+All
+.Nm
+commands are single characters, though some require additional parameters.
+If a command's parameters extend over several lines, then
+each line except for the last must be terminated with a backslash
+.Pq Ql \e .
+.Pp
+In general, at most one command is allowed per line.
+However, most commands accept a print suffix, which is any of
+.Ic p
+.Pq print ,
+.Ic l
+.Pq list ,
+or
+.Ic n
+.Pq enumerate ,
+to print the last line affected by the command.
+.Pp
+.Nm
+recognizes the following commands.
+The commands are shown together with
+the default address or address range supplied if none is specified
+.Pq in parentheses ,
+and other possible arguments on the right.
+.Bl -tag -width Dxxs
+.It (.) Ns Ic a
+Appends text to the buffer after the addressed line.
+Text is entered in input mode.
+The current address is set to last line entered.
+.It (.,.) Ns Ic c
+Changes lines in the buffer.
+The addressed lines are deleted from the buffer,
+and text is appended in their place.
+Text is entered in input mode.
+The current address is set to last line entered.
+.It (.,.) Ns Ic d
+Deletes the addressed lines from the buffer.
+If there is a line after the deleted range, then the current address is set
+to this line.
+Otherwise the current address is set to the line before the deleted range.
+.It Ic e Ar file
+Edits
+.Ar file ,
+and sets the default filename.
+If
+.Ar file
+is not specified, then the default filename is used.
+Any lines in the buffer are deleted before the new file is read.
+The current address is set to the last line read.
+.It Ic e No \&! Ns Ar command
+Edits the standard output of
+.No \&! Ns Ar command ,
+(see
+.Ic \&! Ns Ar command
+below).
+The default filename is unchanged.
+Any lines in the buffer are deleted before the output of
+.Ar command
+is read.
+The current address is set to the last line read.
+.It Ic E Ar file
+Edits
+.Ar file
+unconditionally.
+This is similar to the
+.Ic e
+command, except that unwritten changes are discarded without warning.
+The current address is set to the last line read.
+.It Ic f Ar file
+Sets the default filename to
+.Ar file .
+If
+.Ar file
+is not specified, then the default unescaped filename is printed.
+.Sm off
+.It Xo
+.Pf (1,$) Ic g No /
+.Ar re No / Ar command-list
+.Xc
+.Sm on
+Mark each addressed line matching the regular expression
+.Ar re
+for modification.
+The current address is set to each marked line in turn, and then the
+.Ar command-list
+is executed each time.
+The command-list can change the current line number,
+and it is not changed back after the command-list ended.
+When a marked line is changed, it is unmarked
+and the command-list won't be executed for it any more.
+If no lines were matched,
+the current line number remains unchanged.
+.Pp
+Each command in
+.Ar command-list
+must be on a separate line,
+and every line except for the last must be terminated by a backslash
+.Pq Sq \e .
+Any commands are allowed, except for
+.Ic g ,
+.Ic G ,
+.Ic v ,
+and
+.Ic V .
+An empty
+.Ar command-list
+is equivalent to a
+.Ic p
+command \(em unlike for the
+.Cm G
+command, where an empty command-list does nothing, and unlike an empty
+command, which is equivalent to the command
+.Cm +p .
+If the
+.Ar command-list
+is empty, the trailing slash can be omitted.
+.Sm off
+.It (1,$) Ic G No / Ar re No /
+.Sm on
+Interactively edits the addressed lines matching a regular expression
+.Ar re .
+The trailing slash after
+.Ar re
+can be omitted.
+For each matching line, the line is printed, the current address is set,
+and the user is prompted to enter a
+.Ar command-list .
+At the end of the
+.Ic G
+command, the current address is set to the last line affected by
+.Pq the last
+command-list.
+If no lines were matched,
+the current line number remains unchanged.
+.Pp
+The format of
+.Ar command-list
+is the same as that of the
+.Ic g
+command, but an empty command list does nothing.
+A single
+.Sq &
+repeats the last non-empty command list.
+.It Ic H
+Toggles the printing of error explanations.
+By default, explanations are not printed.
+It is recommended that
+.Nm
+scripts begin with this command to aid in debugging.
+.It Ic h
+Prints an explanation of the last error.
+.It (.) Ns Ic i
+Inserts text in the buffer before the current line.
+Text is entered in input mode.
+The current address is set to the last line entered.
+.It (.,+) Ns Ic j
+Joins the addressed lines.
+The addressed lines are deleted from the buffer and replaced by a single
+line containing their joined text.
+The current address is set to the resultant line.
+.It (.) Ns Ic k Ns Ar lc
+Marks a line with a lower case letter
+.Ar lc .
+The line can then be addressed as
+.Ic ' Ns Ar lc
+(i.e., a single quote followed by
+.Ar lc )
+in subsequent commands.
+The mark is not cleared until the line is deleted or otherwise modified.
+.It (.,.) Ns Ic l
+Prints the addressed lines unambiguously.
+The current address is set to the last line printed.
+.It (.,.) Ns Ic m Ns (.)
+Moves lines in the buffer.
+The addressed lines are moved to after the
+right-hand destination address, which may be the address
+.Ad 0
+.Pq zero .
+The current address is set to the last line moved.
+.It (.,.) Ns Ic n
+Prints the addressed lines along with their line numbers.
+The current address is set to the last line printed.
+.It (.,.) Ns Ic p
+Prints the addressed lines.
+The current address is set to the last line printed.
+.It Ic P
+Toggles the command prompt on and off.
+Unless a prompt was specified with the command-line option
+.Fl p Ar string ,
+the command prompt is by default turned off.
+.It Ic q
+Quits
+.Nm ed .
+.It Ic Q
+Quits
+.Nm
+unconditionally.
+This is similar to the
+.Ic q
+command, except that unwritten changes are discarded without warning.
+.It ($) Ns Ic r Ar file
+Reads
+.Ar file
+to after the addressed line.
+If
+.Ar file
+is not specified, then the default filename is used.
+If there was no default filename prior to the command,
+then the default filename is set to
+.Ar file .
+Otherwise, the default filename is unchanged.
+The current address is set to the last line read.
+.It ($) Ns Ic r No \&! Ns Ar command
+Reads to after the addressed line the standard output of
+.No \&! Ns Ar command ,
+(see
+.Ic \&! Ns Ar command
+below).
+The default filename is unchanged.
+The current address is set to the last line read.
+.Sm off
+.It Xo
+.Pf (.,.) Ic s No / Ar re
+.No / Ar replacement No /\ \&
+.Pf (.,.) Ic s No / Ar re
+.No / Ar replacement No / Ic g\ \&
+.No (.,.) Ic s No / Ar re
+.No / Ar replacement No / Ar n
+.Xc
+.Sm on
+Replaces text in the addressed lines matching a regular expression
+.Ar re
+with
+.Ar replacement .
+By default, only the first match in each line is replaced.
+If the
+.Ic g
+.Pq global
+suffix is given, then every match is replaced.
+The
+.Ar n
+suffix, where
+.Ar n
+is a positive number, causes only the
+.Ar n Ns th
+match to be replaced.
+It is an error if no substitutions are performed on any of the addressed
+lines.
+The current address is set the last line affected.
+.Pp
+.Ar re
+and
+.Ar replacement
+may be delimited by any character other than space and newline
+(see the
+.Ic s
+command below).
+If one or two of the last delimiters is omitted, then the last line
+affected is printed as though the print suffix
+.Ic p
+were specified.
+.Pp
+An unescaped
+.Ql &
+in
+.Ar replacement
+is replaced by the currently matched text.
+The character sequence
+.Pf \e Ar m ,
+where
+.Ar m
+is a number in the range [1,9], is replaced by the
+.Ar m Ns th
+backreference expression of the matched text.
+If
+.Ar replacement
+consists of a single
+.Ql % ,
+then
+.Ar replacement
+from the last substitution is used.
+Newlines may be embedded in
+.Ar replacement
+if they are escaped with a backslash
+.Pq Ql \e .
+.It (.,.) Ns Ic s
+Repeats the last substitution.
+This form of the
+.Ic s
+command accepts a count suffix
+.Ar n ,
+or any combination of the characters
+.Ic r ,
+.Ic g ,
+and
+.Ic p .
+If a count suffix
+.Ar n
+is given, then only the
+.Ar n Ns th
+match is replaced.
+The
+.Ic r
+suffix causes the regular expression of the last search to be used
+instead of that of the last substitution.
+The
+.Ic g
+suffix toggles the global suffix of the last substitution.
+The
+.Ic p
+suffix toggles the print suffix of the last substitution.
+The current address is set to the last line affected.
+.It (.,.) Ns Ic t Ns (.)
+Copies
+.Pq i.e., transfers
+the addressed lines to after the right-hand destination address,
+which may be the address
+.Ad 0
+.Pq zero .
+The current address is set to the last line copied.
+.It Ic u
+Undoes the last command and restores the current address
+to what it was before the command.
+The global commands
+.Ic g ,
+.Ic G ,
+.Ic v ,
+and
+.Ic V
+are treated as a single command by undo.
+.Ic u
+is its own inverse.
+.Sm off
+.It Xo
+.Pf (1,$) Ic v No / Ar re
+.Pf / Ar command-list
+.Xc
+.Sm on
+The same as the
+.Ic g
+command, except that it applies
+.Ar command-list
+to each of the addressed lines not matching the regular expression
+.Ar re .
+.Sm off
+.It Xo
+.Pf (1,$) Ic V No /
+.Ar re No /
+.Xc
+.Sm on
+The same as the
+.Ic G
+command, except that it interactively edits the addressed lines
+not matching the regular expression
+.Ar re .
+.It (1,$) Ns Ic w Ar file
+Writes the addressed lines to
+.Ar file .
+Any previous contents of
+.Ar file
+are lost without warning.
+If there is no default filename, then the default filename is set to
+.Ar file ,
+otherwise it is unchanged.
+If no filename is specified, then the default filename is used.
+The current address is unchanged.
+.It (1,$) Ns Ic wq Ar file
+Writes the addressed lines to
+.Ar file ,
+and then executes a
+.Ic q
+command.
+.It (1,$) Ns Ic w No \&! Ns Ar command
+Writes the addressed lines to the standard input of
+.No \&! Ns Ar command ,
+(see
+.Ic \&! Ns Ar command
+below).
+The default filename and current address are unchanged.
+.It (1,$) Ns Ic W Ar file
+Appends the addressed lines to the end of
+.Ar file .
+This is similar to the
+.Ic w
+command, except that the previous contents of file are not clobbered.
+The current address is unchanged.
+.It (+) Ns Ic z Ns Ar n
+Scrolls
+.Ar n
+lines at a time starting at addressed line.
+If
+.Ar n
+is not specified, then the current window size is used.
+The current address is set to the last line printed.
+.It ($) Ns Ic =
+Prints the line number of the addressed line.
+.It (+)
+An address without a command prints the addressed line
+and sets the current address to that line.
+If the address is also omitted, it defaults to the next line (+).
+.It Ic \&! Ns Ar command
+Executes
+.Ar command
+via
+.Xr sh 1 .
+If the first character of
+.Ar command
+is
+.Sq !\& ,
+then it is replaced by text of the previous
+.Ic \&! Ns Ar command .
+.Nm
+does not process
+.Ar command
+for
+.Sq \e
+.Pq backslash
+escapes.
+However, an unescaped
+.Sq %
+is replaced by the default filename.
+When the shell returns from execution, a
+.Sq \&!
+is printed to the standard output.
+The current line is unchanged.
+.El
+.Sh ASYNCHRONOUS EVENTS
+.Bl -tag -width "SIGWINCH"
+.It Dv SIGHUP
+If the current buffer has changed since it was last written,
+.Nm
+attempts to write the buffer to the file
+.Pa ed.hup .
+Nothing is written to the currently remembered file, and
+.Nm
+exits.
+.It Dv SIGINT
+When an interrupt occurs,
+.Nm
+prints
+.Sq ?\en
+and returns to command mode.
+If interrupted during text input,
+the text already input is written to the current buffer,
+as if text input had been normally terminated.
+.It Dv SIGQUIT
+This signal is ignored.
+.It Dv SIGWINCH
+The screen is resized.
+.El
+.Sh FILES
+.Bl -tag -width /tmp/ed.* -compact
+.It Pa /tmp/ed.*
+buffer file
+.It Pa ed.hup
+where
+.Nm
+attempts to write the buffer if the terminal hangs up
+.El
+.Sh EXIT STATUS
+.Ex -std ed
+.Sh DIAGNOSTICS
+When an error occurs,
+.Nm
+prints a
+.Sq \&?
+and either returns to command mode or exits if its input is from a script.
+An explanation of the last error can be printed with the
+.Ic h
+.Pq help
+command.
+.Pp
+Since the
+.Ic g
+.Pq global
+command masks any errors from failed searches and substitutions,
+it can be used to perform conditional operations in scripts; e.g.,
+.Pp
+.Dl g/old/s//new/
+.Pp
+replaces any occurrences of
+.Qq old
+with
+.Qq new .
+.Pp
+If the
+.Ic u
+.Pq undo
+command occurs in a global command list,
+then the command list is executed only once.
+.Pp
+If diagnostics are not disabled, attempting to quit
+.Nm
+or edit another file before writing a modified buffer results in an error.
+If the command is entered a second time, it succeeds,
+but any changes to the buffer are lost.
+.Sh SEE ALSO
+.Xr sed 1 ,
+.Xr sh 1 ,
+.Xr vi 1 ,
+.Xr re_format 7
+.Rs
+.\" 4.4BSD USD:9
+.%A B. W. Kernighan
+.%T A Tutorial Introduction to the UNIX Text Editor
+.Re
+.Rs
+.\" 4.4BSD USD:10
+.%A B. W. Kernighan
+.%T Advanced Editing on UNIX
+.Re
+.Rs
+.%A B. W. Kernighan
+.%A P. J. Plauger
+.%B Software Tools in Pascal
+.%O Addison-Wesley
+.%D 1981
+.Re
+.Sh STANDARDS
+The
+.Nm
+utility is compliant with the
+.St -p1003.1-2008
+specification.
+.Pp
+The commands
+.Cm s
+(to repeat the last substitution),
+.Cm W ,
+.Cm wq ,
+and
+.Cm z
+as well as the address specifier
+.Sq %
+are extensions to that specification.
+.Pp
+The
+.St -p1003.1-2008
+specification says the
+.Sq ^
+address specifier is neither required nor prohibited;
+additionally, it says behaviour for the
+.Fl
+option is
+.Dq unspecified .
+.Sh HISTORY
+An
+.Nm
+command appeared in
+.At v1 .
+.Sh CAVEATS
+.Nm
+processes
+.Ar file
+arguments for backslash escapes, i.e., in a filename,
+any characters preceded by a backslash
+.Pq Ql \e
+are interpreted literally.
+.Pp
+If a text
+.Pq non-binary
+file is not terminated by a newline character,
+then
+.Nm
+appends one on reading/writing it.
+In the case of a binary file,
+.Nm
+does not append a newline on reading/writing.
diff --git a/bin/ed/ed.h b/bin/ed/ed.h
new file mode 100644
index 0000000..12d7e3d
--- /dev/null
+++ b/bin/ed/ed.h
@@ -0,0 +1,201 @@
+/*	$OpenBSD: ed.h,v 1.22 2016/03/27 00:43:38 mmcc Exp $	*/
+/*	$NetBSD: ed.h,v 1.23 1995/03/21 09:04:40 cgd Exp $	*/
+
+/* ed.h: type and constant definitions for the ed editor. */
+/*
+ * Copyright (c) 1993 Andrew Moore
+ * 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.
+ *
+ * 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.
+ *
+ *	@(#)ed.h,v 1.5 1994/02/01 00:34:39 alm Exp
+ */
+
+#include <limits.h>
+#include <regex.h>
+#include <signal.h>
+
+#define ERR		(-2)
+#define EMOD		(-3)
+#define FATAL		(-4)
+
+#define MINBUFSZ 512		/* minimum buffer size - must be > 0 */
+#define SE_MAX 30		/* max subexpressions in a regular expression */
+#define LINECHARS INT_MAX	/* max chars per line */
+
+/* gflags */
+#define GLB 001		/* global command */
+#define GPR 002		/* print after command */
+#define GLS 004		/* list after command */
+#define GNP 010		/* enumerate after command */
+#define GSG 020		/* global substitute */
+
+/* Line node */
+typedef struct	line {
+	struct line	*q_forw;
+	struct line	*q_back;
+	off_t		seek;		/* address of line in scratch buffer */
+	int		len;		/* length of line */
+} line_t;
+
+
+typedef struct undo {
+
+/* type of undo nodes */
+#define UADD	0
+#define UDEL 	1
+#define UMOV	2
+#define VMOV	3
+
+	int type;			/* command type */
+	line_t	*h;			/* head of list */
+	line_t  *t;			/* tail of list */
+} undo_t;
+
+#ifndef max
+# define max(a,b) ((a) > (b) ? (a) : (b))
+#endif
+#ifndef min
+# define min(a,b) ((a) < (b) ? (a) : (b))
+#endif
+
+#define INC_MOD(l, k)	((l) + 1 > (k) ? 0 : (l) + 1)
+#define DEC_MOD(l, k)	((l) - 1 < 0 ? (k) : (l) - 1)
+
+/* SPL1: disable some interrupts (requires reliable signals) */
+#define SPL1() mutex++
+
+/* SPL0: enable all interrupts; check signal flags (requires reliable signals) */
+#define SPL0()						\
+	do {						\
+		if (--mutex == 0) {			\
+			if (sighup)			\
+				handle_hup(SIGHUP);	\
+			if (sigint)			\
+				handle_int(SIGINT);	\
+		}					\
+	} while (0)
+
+/* STRTOI: convert a string to int */
+#define STRTOI(i, p) { \
+	long l = strtol(p, &p, 10); \
+	if (l <= INT_MIN || l >= INT_MAX) { \
+		seterrmsg("number out of range"); \
+	    	i = 0; \
+		return ERR; \
+	} else \
+		i = (int)l; \
+}
+
+/* REALLOC: assure at least a minimum size for buffer b */
+#define REALLOC(b,n,i,err) \
+if ((i) > (n)) { \
+	int ti = (n); \
+	char *ts; \
+	SPL1(); \
+	if ((ts = realloc((b), ti += max((i), MINBUFSZ))) == NULL) { \
+		perror(NULL); \
+		seterrmsg("out of memory"); \
+		SPL0(); \
+		return err; \
+	} \
+	(n) = ti; \
+	(b) = ts; \
+	SPL0(); \
+}
+
+/* REQUE: link pred before succ */
+#define REQUE(pred, succ) (pred)->q_forw = (succ), (succ)->q_back = (pred)
+
+/* INSQUE: insert elem in circular queue after pred */
+#define INSQUE(elem, pred) \
+{ \
+	REQUE((elem), (pred)->q_forw); \
+	REQUE((pred), elem); \
+}
+
+/* remque: remove_lines elem from circular queue */
+#define REMQUE(elem) REQUE((elem)->q_back, (elem)->q_forw);
+
+/* NUL_TO_NEWLINE: overwrite ASCII NULs with newlines */
+#define NUL_TO_NEWLINE(s, l) translit_text(s, l, '\0', '\n')
+
+/* NEWLINE_TO_NUL: overwrite newlines with ASCII NULs */
+#define NEWLINE_TO_NUL(s, l) translit_text(s, l, '\n', '\0')
+
+/* Local Function Declarations */
+void add_line_node(line_t *);
+int build_active_list(int);
+void clear_active_list(void);
+void clear_undo_stack(void);
+int close_sbuf(void);
+int delete_lines(int, int);
+int display_lines(int, int, int);
+int exec_command(void);
+int exec_global(int, int);
+int extract_addr_range(void);
+int extract_subst_tail(int *, int *);
+line_t *get_addressed_line_node(int);
+regex_t *get_compiled_pattern(void);
+char *get_extended_line(int *, int);
+int get_line_node_addr(line_t *);
+char *get_sbuf_line(line_t *);
+int get_tty_line(void);
+void handle_hup(int);
+void handle_int(int);
+int has_trailing_escape(char *, char *);
+void init_buffers(void);
+int open_sbuf(void);
+int pop_undo_stack(void);
+undo_t *push_undo_stack(int, int, int);
+char *put_sbuf_line(char *);
+int put_tty_line(char *, int, int, int);
+void quit(int);
+int read_file(char *, int);
+int search_and_replace(regex_t *, int, int);
+void seterrmsg(char *);
+char *strip_escapes(char *);
+char *translit_text(char *, int, int, int);
+void unmark_line_node(line_t *);
+void unset_active_nodes(line_t *, line_t *);
+int write_file(char *, char *, int, int);
+
+/* global buffers */
+extern char *ibuf;
+extern char *ibufp;
+extern int ibufsz;
+
+/* global flags */
+extern int isbinary;
+extern int isglobal;
+extern int modified;
+
+extern volatile sig_atomic_t mutex;
+extern volatile sig_atomic_t sighup;
+extern volatile sig_atomic_t sigint;
+
+/* global vars */
+extern int addr_last;
+extern int current_addr;
+extern int first_addr;
+extern int lineno;
+extern int second_addr;
diff --git a/bin/ed/glbl.c b/bin/ed/glbl.c
new file mode 100644
index 0000000..90e602c
--- /dev/null
+++ b/bin/ed/glbl.c
@@ -0,0 +1,207 @@
+/*	$OpenBSD: glbl.c,v 1.20 2018/06/04 13:26:21 martijn Exp $	*/
+/*	$NetBSD: glbl.c,v 1.2 1995/03/21 09:04:41 cgd Exp $	*/
+
+/* glob.c: This file contains the global command routines for the ed line
+   editor */
+/*-
+ * Copyright (c) 1993 Andrew Moore, Talke Studio.
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+ */
+
+#include <sys/ioctl.h>
+#include <sys/wait.h>
+
+#include <regex.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "ed.h"
+
+static int set_active_node(line_t *);
+static line_t *next_active_node(void);
+
+/* build_active_list:  add line matching a pattern to the global-active list */
+int
+build_active_list(int isgcmd)
+{
+	regex_t *pat;
+	line_t *lp;
+	int n;
+	char *s;
+	char delimiter;
+
+	if ((delimiter = *ibufp) == ' ' || delimiter == '\n') {
+		seterrmsg("invalid pattern delimiter");
+		return ERR;
+	} else if ((pat = get_compiled_pattern()) == NULL)
+		return ERR;
+	else if (*ibufp == delimiter)
+		ibufp++;
+	clear_active_list();
+	lp = get_addressed_line_node(first_addr);
+	for (n = first_addr; n <= second_addr; n++, lp = lp->q_forw) {
+		if ((s = get_sbuf_line(lp)) == NULL)
+			return ERR;
+		if (isbinary)
+			NUL_TO_NEWLINE(s, lp->len);
+		if ((!regexec(pat, s, 0, NULL, 0)) == isgcmd &&
+		    set_active_node(lp) < 0)
+			return ERR;
+	}
+	return 0;
+}
+
+
+/* exec_global: apply command list in the command buffer to the active
+   lines in a range; return command status */
+int
+exec_global(int interact, int gflag)
+{
+	static char *ocmd = NULL;
+	static int ocmdsz = 0;
+
+	line_t *lp = NULL;
+	int status;
+	int n;
+	char *cmd = NULL;
+
+	if (!interact) {
+		if (!strcmp(ibufp, "\n"))
+			cmd = "p\n";		/* null cmd-list == `p' */
+		else if ((cmd = get_extended_line(&n, 0)) == NULL)
+			return ERR;
+	}
+	clear_undo_stack();
+	while ((lp = next_active_node()) != NULL) {
+		if ((current_addr = get_line_node_addr(lp)) < 0)
+			return ERR;
+		if (interact) {
+			/* print current_addr; get a command in global syntax */
+			if (display_lines(current_addr, current_addr, gflag) < 0)
+				return ERR;
+			while ((n = get_tty_line()) > 0 &&
+			    ibuf[n - 1] != '\n')
+				clearerr(stdin);
+			if (n < 0)
+				return ERR;
+			else if (n == 0) {
+				seterrmsg("unexpected end-of-file");
+				return ERR;
+			} else if (n == 1 && !strcmp(ibuf, "\n"))
+				continue;
+			else if (n == 2 && !strcmp(ibuf, "&\n")) {
+				if (cmd == NULL) {
+					seterrmsg("no previous command");
+					return ERR;
+				} else cmd = ocmd;
+			} else if ((cmd = get_extended_line(&n, 0)) == NULL)
+				return ERR;
+			else {
+				REALLOC(ocmd, ocmdsz, n + 1, ERR);
+				memcpy(ocmd, cmd, n + 1);
+				cmd = ocmd;
+			}
+
+		}
+		ibufp = cmd;
+		for (; *ibufp;)
+			if ((status = extract_addr_range()) < 0 ||
+			    (status = exec_command()) < 0 ||
+			    (status > 0 && (status = display_lines(
+			    current_addr, current_addr, status)) < 0))
+				return status;
+	}
+	return 0;
+}
+
+
+static line_t **active_list;	/* list of lines active in a global command */
+static int active_last;		/* index of last active line in active_list */
+static int active_size;		/* size of active_list */
+static int active_ptr;		/* active_list index (non-decreasing) */
+static int active_ndx;		/* active_list index (modulo active_last) */
+
+/* set_active_node: add a line node to the global-active list */
+static int
+set_active_node(line_t *lp)
+{
+	if (active_last + 1 > active_size) {
+		int ti = active_size;
+		line_t **ts;
+		SPL1();
+		if ((ts = reallocarray(active_list,
+		    (ti += MINBUFSZ), sizeof(line_t **))) == NULL) {
+			perror(NULL);
+			seterrmsg("out of memory");
+			SPL0();
+			return ERR;
+		}
+		active_size = ti;
+		active_list = ts;
+		SPL0();
+	}
+	active_list[active_last++] = lp;
+	return 0;
+}
+
+
+/* unset_active_nodes: remove a range of lines from the global-active list */
+void
+unset_active_nodes(line_t *np, line_t *mp)
+{
+	line_t *lp;
+	int i;
+
+	for (lp = np; lp != mp; lp = lp->q_forw)
+		for (i = 0; i < active_last; i++)
+			if (active_list[active_ndx] == lp) {
+				active_list[active_ndx] = NULL;
+				active_ndx = INC_MOD(active_ndx, active_last - 1);
+				break;
+			} else	active_ndx = INC_MOD(active_ndx, active_last - 1);
+}
+
+
+/* next_active_node: return the next global-active line node */
+static line_t *
+next_active_node(void)
+{
+	while (active_ptr < active_last && active_list[active_ptr] == NULL)
+		active_ptr++;
+	return (active_ptr < active_last) ? active_list[active_ptr++] : NULL;
+}
+
+
+/* clear_active_list: clear the global-active list */
+void
+clear_active_list(void)
+{
+	SPL1();
+	active_size = active_last = active_ptr = active_ndx = 0;
+	free(active_list);
+	active_list = NULL;
+	SPL0();
+}
diff --git a/bin/ed/io.c b/bin/ed/io.c
new file mode 100644
index 0000000..97306be
--- /dev/null
+++ b/bin/ed/io.c
@@ -0,0 +1,343 @@
+/*	$OpenBSD: io.c,v 1.24 2019/06/28 13:41:42 deraadt Exp $	*/
+/*	$NetBSD: io.c,v 1.2 1995/03/21 09:04:43 cgd Exp $	*/
+
+/* io.c: This file contains the i/o routines for the ed line editor */
+/*-
+ * Copyright (c) 1993 Andrew Moore, Talke Studio.
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+ */
+
+#include <regex.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "ed.h"
+
+static int read_stream(FILE *, int);
+static int get_stream_line(FILE *);
+static int write_stream(FILE *, int, int);
+static int put_stream_line(FILE *, char *, int);
+
+extern int scripted;
+
+/* read_file: read a named file/pipe into the buffer; return line count */
+int
+read_file(char *fn, int n)
+{
+	FILE *fp;
+	int size;
+
+
+	fp = (*fn == '!') ? popen(fn + 1, "r") : fopen(strip_escapes(fn), "r");
+	if (fp == NULL) {
+		perror(fn);
+		seterrmsg("cannot open input file");
+		return ERR;
+	} else if ((size = read_stream(fp, n)) < 0)
+		return ERR;
+	 else if ((*fn == '!') ?  pclose(fp) == -1 : fclose(fp) == EOF) {
+		perror(fn);
+		seterrmsg("cannot close input file");
+		return ERR;
+	}
+	if (!scripted)
+		fprintf(stderr, "%d\n", size);
+	return current_addr - n;
+}
+
+
+static char *sbuf;		/* file i/o buffer */
+static int sbufsz;		/* file i/o buffer size */
+int newline_added;		/* if set, newline appended to input file */
+
+/* read_stream: read a stream into the editor buffer; return status */
+static int
+read_stream(FILE *fp, int n)
+{
+	line_t *lp = get_addressed_line_node(n);
+	undo_t *up = NULL;
+	unsigned int size = 0;
+	int o_newline_added = newline_added;
+	int o_isbinary = isbinary;
+	int appended = (n == addr_last);
+	int len;
+
+	isbinary = newline_added = 0;
+	for (current_addr = n; (len = get_stream_line(fp)) > 0; size += len) {
+		SPL1();
+		if (put_sbuf_line(sbuf) == NULL) {
+			SPL0();
+			return ERR;
+		}
+		lp = lp->q_forw;
+		if (up)
+			up->t = lp;
+		else if ((up = push_undo_stack(UADD, current_addr,
+		    current_addr)) == NULL) {
+			SPL0();
+			return ERR;
+		}
+		SPL0();
+	}
+	if (len < 0)
+		return ERR;
+	if (appended && size && o_isbinary && o_newline_added)
+		fputs("newline inserted\n", stderr);
+	else if (newline_added && (!appended || (!isbinary && !o_isbinary)))
+		fputs("newline appended\n", stderr);
+	if (isbinary && newline_added && !appended)
+	    	size += 1;
+	if (!size)
+		newline_added = 1;
+	newline_added = appended ? newline_added : o_newline_added;
+	isbinary = isbinary | o_isbinary;
+	return size;
+}
+
+/* get_stream_line: read a line of text from a stream; return line length */
+static int
+get_stream_line(FILE *fp)
+{
+	int c;
+	int i = 0;
+
+	while (((c = getc(fp)) != EOF || (!feof(fp) &&
+	    !ferror(fp))) && c != '\n') {
+		REALLOC(sbuf, sbufsz, i + 1, ERR);
+		if (!(sbuf[i++] = c))
+			isbinary = 1;
+	}
+	REALLOC(sbuf, sbufsz, i + 2, ERR);
+	if (c == '\n')
+		sbuf[i++] = c;
+	else if (ferror(fp)) {
+		perror(NULL);
+		seterrmsg("cannot read input file");
+		return ERR;
+	} else if (i) {
+		sbuf[i++] = '\n';
+		newline_added = 1;
+	}
+	sbuf[i] = '\0';
+	return (isbinary && newline_added && i) ? --i : i;
+}
+
+
+/* write_file: write a range of lines to a named file/pipe; return line count */
+int
+write_file(char *fn, char *mode, int n, int m)
+{
+	FILE *fp;
+	int size;
+
+	fp = (*fn == '!') ? popen(fn+1, "w") : fopen(strip_escapes(fn), mode);
+	if (fp == NULL) {
+		perror(fn);
+		seterrmsg("cannot open output file");
+		return ERR;
+	} else if ((size = write_stream(fp, n, m)) < 0)
+		return ERR;
+	 else if ((*fn == '!') ?  pclose(fp) == -1 : fclose(fp) == EOF) {
+		perror(fn);
+		seterrmsg("cannot close output file");
+		return ERR;
+	}
+	if (!scripted)
+		fprintf(stderr, "%d\n", size);
+	return n ? m - n + 1 : 0;
+}
+
+
+/* write_stream: write a range of lines to a stream; return status */
+static int
+write_stream(FILE *fp, int n, int m)
+{
+	line_t *lp = get_addressed_line_node(n);
+	unsigned int size = 0;
+	char *s;
+	int len;
+
+	for (; n && n <= m; n++, lp = lp->q_forw) {
+		if ((s = get_sbuf_line(lp)) == NULL)
+			return ERR;
+		len = lp->len;
+		if (n != addr_last || !isbinary || !newline_added)
+			s[len++] = '\n';
+		if (put_stream_line(fp, s, len) < 0)
+			return ERR;
+		size += len;
+	}
+	return size;
+}
+
+
+/* put_stream_line: write a line of text to a stream; return status */
+static int
+put_stream_line(FILE *fp, char *s, int len)
+{
+	while (len--) {
+		if (fputc(*s, fp) == EOF) {
+			perror(NULL);
+			seterrmsg("cannot write file");
+			return ERR;
+		}
+		s++;
+	}
+	return 0;
+}
+
+/* get_extended_line: get a an extended line from stdin */
+char *
+get_extended_line(int *sizep, int nonl)
+{
+	static char *cvbuf = NULL;		/* buffer */
+	static int cvbufsz = 0;			/* buffer size */
+
+	int l, n;
+	char *t = ibufp;
+
+	while (*t++ != '\n')
+		;
+	if ((l = t - ibufp) < 2 || !has_trailing_escape(ibufp, ibufp + l - 1)) {
+		*sizep = l;
+		return ibufp;
+	}
+	*sizep = -1;
+	REALLOC(cvbuf, cvbufsz, l, NULL);
+	memcpy(cvbuf, ibufp, l);
+	*(cvbuf + --l - 1) = '\n'; 	/* strip trailing esc */
+	if (nonl)
+		l--; 			/* strip newline */
+	for (;;) {
+		if ((n = get_tty_line()) < 0)
+			return NULL;
+		else if (n == 0 || ibuf[n - 1] != '\n') {
+			seterrmsg("unexpected end-of-file");
+			return NULL;
+		}
+		REALLOC(cvbuf, cvbufsz, l + n, NULL);
+		memcpy(cvbuf + l, ibuf, n);
+		l += n;
+		if (n < 2 || !has_trailing_escape(cvbuf, cvbuf + l - 1))
+			break;
+		*(cvbuf + --l - 1) = '\n'; 	/* strip trailing esc */
+		if (nonl) l--; 			/* strip newline */
+	}
+	REALLOC(cvbuf, cvbufsz, l + 1, NULL);
+	cvbuf[l] = '\0';
+	*sizep = l;
+	return cvbuf;
+}
+
+
+/* get_tty_line: read a line of text from stdin; return line length */
+int
+get_tty_line(void)
+{
+	int oi = 0;
+	int i = 0;
+	int c;
+
+	for (;;)
+		switch (c = getchar()) {
+		default:
+			oi = 0;
+			REALLOC(ibuf, ibufsz, i + 2, ERR);
+			if (!(ibuf[i++] = c)) isbinary = 1;
+			if (c != '\n')
+				continue;
+			lineno++;
+			ibuf[i] = '\0';
+			ibufp = ibuf;
+			return i;
+		case EOF:
+			if (ferror(stdin)) {
+				perror("stdin");
+				seterrmsg("cannot read stdin");
+				clearerr(stdin);
+				ibufp = NULL;
+				return ERR;
+			} else {
+				clearerr(stdin);
+				if (i != oi) {
+					oi = i;
+					continue;
+				} else if (i)
+					ibuf[i] = '\0';
+				ibufp = ibuf;
+				return i;
+			}
+		}
+}
+
+
+
+#define ESCAPES "\a\b\f\n\r\t\v\\$"
+#define ESCCHARS "abfnrtv\\$"
+
+extern int rows;
+extern int cols;
+
+/* put_tty_line: print text to stdout */
+int
+put_tty_line(char *s, int l, int n, int gflag)
+{
+	int col = 0;
+	char *cp;
+
+	if (gflag & GNP) {
+		printf("%d\t", n);
+		col = 8;
+	}
+	for (; l--; s++) {
+		if ((gflag & GLS) && ++col > cols) {
+			fputs("\\\n", stdout);
+			col = 1;
+		}
+		if (gflag & GLS) {
+			if (31 < *s && *s < 127 && *s != '\\' && *s != '$')
+				putchar(*s);
+			else {
+				putchar('\\');
+				col++;
+				if (*s && (cp = strchr(ESCAPES, *s)) != NULL)
+					putchar(ESCCHARS[cp - ESCAPES]);
+				else {
+					putchar((((unsigned char) *s & 0300) >> 6) + '0');
+					putchar((((unsigned char) *s & 070) >> 3) + '0');
+					putchar(((unsigned char) *s & 07) + '0');
+					col += 2;
+				}
+			}
+
+		} else
+			putchar(*s);
+	}
+	if (gflag & GLS)
+		putchar('$');
+	putchar('\n');
+	return 0;
+}
diff --git a/bin/ed/main.c b/bin/ed/main.c
new file mode 100644
index 0000000..dc73dd9
--- /dev/null
+++ b/bin/ed/main.c
@@ -0,0 +1,1394 @@
+/*	$OpenBSD: main.c,v 1.66 2019/06/28 13:34:59 deraadt Exp $	*/
+/*	$NetBSD: main.c,v 1.3 1995/03/21 09:04:44 cgd Exp $	*/
+
+/* main.c: This file contains the main control and user-interface routines
+   for the ed line editor. */
+/*-
+ * Copyright (c) 1993 Andrew Moore, Talke Studio.
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+ */
+
+/*
+ * CREDITS
+ *
+ *	This program is based on the editor algorithm described in
+ *	Brian W. Kernighan and P. J. Plauger's book "Software Tools
+ *	in Pascal," Addison-Wesley, 1981.
+ *
+ *	The buffering algorithm is attributed to Rodney Ruddock of
+ *	the University of Guelph, Guelph, Ontario.
+ *
+ */
+
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+
+#include <ctype.h>
+#include <err.h>
+#include <errno.h>
+#include <limits.h>
+#include <pwd.h>
+#include <regex.h>
+#include <setjmp.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "ed.h"
+
+void signal_hup(int);
+void signal_int(int);
+void handle_winch(int);
+
+static int next_addr(void);
+static int check_addr_range(int, int);
+static int get_matching_node_addr(regex_t *, int);
+static char *get_filename(int);
+static int get_shell_command(void);
+static int append_lines(int);
+static int join_lines(int, int);
+static int move_lines(int);
+static int copy_lines(int);
+static int mark_line_node(line_t *, int);
+static int get_marked_node_addr(int);
+static line_t *dup_line_node(line_t *);
+
+sigjmp_buf env;
+
+/* static buffers */
+static char errmsg[PATH_MAX + 40];	/* error message buffer */
+static char *shcmd;		/* shell command buffer */
+static int shcmdsz;		/* shell command buffer size */
+static int shcmdi;		/* shell command buffer index */
+static char old_filename[PATH_MAX];	/* default filename */
+
+/* global buffers */
+char *ibuf;			/* ed command-line buffer */
+int ibufsz;			/* ed command-line buffer size */
+char *ibufp;			/* pointer to ed command-line buffer */
+
+/* global flags */
+int garrulous = 0;		/* if set, print all error messages */
+int isbinary;			/* if set, buffer contains ASCII NULs */
+int isglobal;			/* if set, doing a global command */
+int modified;			/* if set, buffer modified since last write */
+int scripted = 0;		/* if set, suppress diagnostics */
+int interactive = 0;		/* if set, we are in interactive mode */
+
+volatile sig_atomic_t mutex = 0;  /* if set, signals set flags */
+volatile sig_atomic_t sighup = 0; /* if set, sighup received while mutex set */
+volatile sig_atomic_t sigint = 0; /* if set, sigint received while mutex set */
+
+/* if set, signal handlers are enabled */
+volatile sig_atomic_t sigactive = 0;
+
+int current_addr;		/* current address in editor buffer */
+int addr_last;			/* last address in editor buffer */
+int lineno;			/* script line number */
+static char *prompt;		/* command-line prompt */
+static char *dps = "*";		/* default command-line prompt */
+
+static const char usage[] = "usage: %s [-] [-s] [-p string] [file]\n";
+
+static char *home;		/* home directory */
+
+void
+seterrmsg(char *s)
+{
+	strlcpy(errmsg, s, sizeof(errmsg));
+}
+
+/* ed: line editor */
+int
+main(volatile int argc, char ** volatile argv)
+{
+	int c, n;
+	int status = 0;
+
+	if (pledge("stdio rpath wpath cpath proc exec tty", NULL) == -1)
+		err(1, "pledge");
+
+	home = getenv("HOME");
+
+top:
+	while ((c = getopt(argc, argv, "p:sx")) != -1)
+		switch (c) {
+		case 'p':				/* set prompt */
+			dps = prompt = optarg;
+			break;
+		case 's':				/* run script */
+			scripted = 1;
+			break;
+		case 'x':				/* use crypt */
+			fprintf(stderr, "crypt unavailable\n?\n");
+			break;
+		default:
+			fprintf(stderr, usage, argv[0]);
+			exit(1);
+		}
+	argv += optind;
+	argc -= optind;
+	if (argc && **argv == '-') {
+		scripted = 1;
+		if (argc > 1) {
+			optind = 1;
+			goto top;
+		}
+		argv++;
+		argc--;
+	}
+
+	if (!(interactive = isatty(0))) {
+		struct stat sb;
+
+		/* assert: pipes show up as fifo's when fstat'd */
+		if (fstat(STDIN_FILENO, &sb) || !S_ISFIFO(sb.st_mode)) {
+			if (lseek(STDIN_FILENO, 0, SEEK_CUR)) {
+				interactive = 1;
+				setvbuf(stdout, NULL, _IOLBF, 0);
+			}
+		}
+	}
+
+	/* assert: reliable signals! */
+	if (isatty(STDIN_FILENO)) {
+		handle_winch(SIGWINCH);
+		signal(SIGWINCH, handle_winch);
+	}
+	signal(SIGHUP, signal_hup);
+	signal(SIGQUIT, SIG_IGN);
+	signal(SIGINT, signal_int);
+	if (sigsetjmp(env, 1)) {
+		status = -1;
+		fputs("\n?\n", stderr);
+		seterrmsg("interrupt");
+	} else {
+		init_buffers();
+		sigactive = 1;			/* enable signal handlers */
+		if (argc && **argv) {
+			if (read_file(*argv, 0) < 0 && !interactive)
+				quit(2);
+			else if (**argv != '!')
+				strlcpy(old_filename, *argv,
+				    sizeof old_filename);
+		} else if (argc) {
+			fputs("?\n", stderr);
+			if (**argv == '\0')
+				seterrmsg("invalid filename");
+			if (!interactive)
+				quit(2);
+		}
+	}
+	for (;;) {
+		if (status < 0 && garrulous)
+			fprintf(stderr, "%s\n", errmsg);
+		if (prompt) {
+			fputs(prompt, stdout);
+			fflush(stdout);
+		}
+		if ((n = get_tty_line()) < 0) {
+			status = ERR;
+			continue;
+		} else if (n == 0) {
+			if (modified && !scripted) {
+				fputs("?\n", stderr);
+				seterrmsg("warning: file modified");
+				if (!interactive) {
+					if (garrulous)
+						fprintf(stderr,
+						    "script, line %d: %s\n",
+						    lineno, errmsg);
+					quit(2);
+				}
+				clearerr(stdin);
+				modified = 0;
+				status = EMOD;
+				continue;
+			} else
+				quit(0);
+		} else if (ibuf[n - 1] != '\n') {
+			/* discard line */
+			seterrmsg("unexpected end-of-file");
+			clearerr(stdin);
+			status = ERR;
+			continue;
+		}
+		isglobal = 0;
+		if ((status = extract_addr_range()) >= 0 &&
+		    (status = exec_command()) >= 0)
+			if (!status || (status &&
+			    (status = display_lines(current_addr, current_addr,
+				status)) >= 0))
+				continue;
+		switch (status) {
+		case EOF:
+			quit(0);
+			break;
+		case EMOD:
+			modified = 0;
+			fputs("?\n", stderr);		/* give warning */
+			seterrmsg("warning: file modified");
+			if (!interactive) {
+				if (garrulous)
+					fprintf(stderr,
+					    "script, line %d: %s\n",
+					    lineno, errmsg);
+				quit(2);
+			}
+			break;
+		case FATAL:
+			if (!interactive) {
+				if (garrulous)
+					fprintf(stderr,
+					    "script, line %d: %s\n",
+					    lineno, errmsg);
+			} else if (garrulous)
+				fprintf(stderr, "%s\n", errmsg);
+			quit(3);
+			break;
+		default:
+			fputs("?\n", stderr);
+			if (!interactive) {
+				if (garrulous)
+					fprintf(stderr,
+					    "script, line %d: %s\n",
+					    lineno, errmsg);
+				quit(2);
+			}
+			break;
+		}
+	}
+	/*NOTREACHED*/
+}
+
+int first_addr, second_addr, addr_cnt;
+
+/* extract_addr_range: get line addresses from the command buffer until an
+   illegal address is seen; return status */
+int
+extract_addr_range(void)
+{
+	int addr;
+
+	addr_cnt = 0;
+	first_addr = second_addr = current_addr;
+	while ((addr = next_addr()) >= 0) {
+		addr_cnt++;
+		first_addr = second_addr;
+		second_addr = addr;
+		if (*ibufp != ',' && *ibufp != ';')
+			break;
+		else if (*ibufp++ == ';')
+			current_addr = addr;
+	}
+	if ((addr_cnt = min(addr_cnt, 2)) == 1 || second_addr != addr)
+		first_addr = second_addr;
+	return (addr == ERR) ? ERR : 0;
+}
+
+
+#define	SKIP_BLANKS() \
+	do { \
+		while (isspace((unsigned char)*ibufp) && *ibufp != '\n') \
+			ibufp++; \
+	} while (0)
+
+#define MUST_BE_FIRST() \
+	do { \
+		if (!first) { \
+			seterrmsg("invalid address"); \
+			return ERR; \
+		} \
+	} while (0)
+	
+
+/*  next_addr: return the next line address in the command buffer */
+static int
+next_addr(void)
+{
+	char *hd;
+	int addr = current_addr;
+	int n;
+	int first = 1;
+	int c;
+
+	SKIP_BLANKS();
+	for (hd = ibufp;; first = 0)
+		switch ((c = (unsigned char)*ibufp)) {
+		case '+':
+		case '\t':
+		case ' ':
+		case '-':
+		case '^':
+			ibufp++;
+			SKIP_BLANKS();
+			if (isdigit((unsigned char)*ibufp)) {
+				STRTOI(n, ibufp);
+				addr += (c == '-' || c == '^') ? -n : n;
+			} else if (!isspace(c))
+				addr += (c == '-' || c == '^') ? -1 : 1;
+			break;
+		case '0': case '1': case '2':
+		case '3': case '4': case '5':
+		case '6': case '7': case '8': case '9':
+			MUST_BE_FIRST();
+			STRTOI(addr, ibufp);
+			break;
+		case '.':
+		case '$':
+			MUST_BE_FIRST();
+			ibufp++;
+			addr = (c == '.') ? current_addr : addr_last;
+			break;
+		case '/':
+		case '?':
+			MUST_BE_FIRST();
+			if ((addr = get_matching_node_addr(
+			    get_compiled_pattern(), c == '/')) < 0)
+				return ERR;
+			else if (c == *ibufp)
+				ibufp++;
+			break;
+		case '\'':
+			MUST_BE_FIRST();
+			ibufp++;
+			if ((addr = get_marked_node_addr((unsigned char)*ibufp++)) < 0)
+				return ERR;
+			break;
+		case '%':
+		case ',':
+		case ';':
+			if (first) {
+				ibufp++;
+				addr_cnt++;
+				second_addr = (c == ';') ? current_addr : 1;
+				if ((addr = next_addr()) < 0)
+					addr = addr_last;
+				break;
+			}
+			/* FALLTHROUGH */
+		default:
+			if (ibufp == hd)
+				return EOF;
+			else if (addr < 0 || addr_last < addr) {
+				seterrmsg("invalid address");
+				return ERR;
+			} else
+				return addr;
+		}
+	/* NOTREACHED */
+}
+
+
+/* GET_THIRD_ADDR: get a legal address from the command buffer */
+#define GET_THIRD_ADDR(addr) \
+	do { \
+		int ol1, ol2; \
+		\
+		ol1 = first_addr; \
+		ol2 = second_addr; \
+		if (extract_addr_range() < 0) \
+			return ERR; \
+		else if (addr_cnt == 0) { \
+			seterrmsg("destination expected"); \
+			return ERR; \
+		} else if (second_addr < 0 || addr_last < second_addr) { \
+			seterrmsg("invalid address"); \
+			return ERR; \
+		} \
+		addr = second_addr; \
+		first_addr = ol1; \
+		second_addr = ol2; \
+	} while (0)
+
+
+/* GET_COMMAND_SUFFIX: verify the command suffix in the command buffer */
+#define GET_COMMAND_SUFFIX() \
+	do { \
+		int done = 0; \
+		do { \
+			switch (*ibufp) { \
+			case 'p': \
+				gflag |= GPR; \
+				ibufp++; \
+				break; \
+			case 'l': \
+				gflag |= GLS; \
+				ibufp++; \
+				break; \
+			case 'n': \
+				gflag |= GNP; \
+				ibufp++; \
+				break; \
+			default: \
+				done++; \
+			} \
+		} while (!done); \
+		if (*ibufp++ != '\n') { \
+			seterrmsg("invalid command suffix"); \
+			return ERR; \
+		} \
+	} while (0)
+
+/* sflags */
+#define SGG 001		/* complement previous global substitute suffix */
+#define SGP 002		/* complement previous print suffix */
+#define SGR 004		/* use last regex instead of last pat */
+#define SGF 010		/* repeat last substitution */
+
+int patlock = 0;	/* if set, pattern not freed by get_compiled_pattern() */
+
+volatile sig_atomic_t rows = 22;	/* scroll length: ws_row - 2 */
+volatile sig_atomic_t cols = 72;	/* wrap column */
+
+/* exec_command: execute the next command in command buffer; return print
+   request, if any */
+int
+exec_command(void)
+{
+	extern int u_current_addr;
+	extern int u_addr_last;
+
+	static regex_t *pat = NULL;
+	static int sgflag = 0;
+	static int sgnum = 0;
+
+	regex_t *tpat;
+	char *fnp;
+	int gflag = 0;
+	int sflags = 0;
+	int addr = 0;
+	int n = 0;
+	int c;
+
+	SKIP_BLANKS();
+	switch ((c = (unsigned char)*ibufp++)) {
+	case 'a':
+		GET_COMMAND_SUFFIX();
+		if (!isglobal) clear_undo_stack();
+		if (append_lines(second_addr) < 0)
+			return ERR;
+		break;
+	case 'c':
+		if (check_addr_range(current_addr, current_addr) < 0)
+			return ERR;
+		GET_COMMAND_SUFFIX();
+		if (!isglobal) clear_undo_stack();
+		if (delete_lines(first_addr, second_addr) < 0 ||
+		    append_lines(current_addr) < 0)
+			return ERR;
+		break;
+	case 'd':
+		if (check_addr_range(current_addr, current_addr) < 0)
+			return ERR;
+		GET_COMMAND_SUFFIX();
+		if (!isglobal) clear_undo_stack();
+		if (delete_lines(first_addr, second_addr) < 0)
+			return ERR;
+		else if ((addr = INC_MOD(current_addr, addr_last)) != 0)
+			current_addr = addr;
+		break;
+	case 'e':
+		if (modified && !scripted)
+			return EMOD;
+		/* FALLTHROUGH */
+	case 'E':
+		if (addr_cnt > 0) {
+			seterrmsg("unexpected address");
+			return ERR;
+		} else if (!isspace((unsigned char)*ibufp)) {
+			seterrmsg("unexpected command suffix");
+			return ERR;
+		} else if ((fnp = get_filename(1)) == NULL)
+			return ERR;
+		GET_COMMAND_SUFFIX();
+		if (delete_lines(1, addr_last) < 0)
+			return ERR;
+		clear_undo_stack();
+		if (close_sbuf() < 0)
+			return ERR;
+		else if (open_sbuf() < 0)
+			return FATAL;
+		if (read_file(fnp, 0) < 0)
+			return ERR;
+		clear_undo_stack();
+		modified = 0;
+		u_current_addr = u_addr_last = -1;
+		break;
+	case 'f':
+		if (addr_cnt > 0) {
+			seterrmsg("unexpected address");
+			return ERR;
+		} else if (!isspace((unsigned char)*ibufp)) {
+			seterrmsg("unexpected command suffix");
+			return ERR;
+		} else if ((fnp = get_filename(1)) == NULL)
+			return ERR;
+		else if (*fnp == '!') {
+			seterrmsg("invalid redirection");
+			return ERR;
+		}
+		GET_COMMAND_SUFFIX();
+		puts(strip_escapes(fnp));
+		break;
+	case 'g':
+	case 'v':
+	case 'G':
+	case 'V':
+		if (isglobal) {
+			seterrmsg("cannot nest global commands");
+			return ERR;
+		} else if (check_addr_range(1, addr_last) < 0)
+			return ERR;
+		else if (build_active_list(c == 'g' || c == 'G') < 0)
+			return ERR;
+		else if ((n = (c == 'G' || c == 'V')))
+			GET_COMMAND_SUFFIX();
+		isglobal++;
+		if (exec_global(n, gflag) < 0)
+			return ERR;
+		break;
+	case 'h':
+		if (addr_cnt > 0) {
+			seterrmsg("unexpected address");
+			return ERR;
+		}
+		GET_COMMAND_SUFFIX();
+		if (*errmsg) fprintf(stderr, "%s\n", errmsg);
+		break;
+	case 'H':
+		if (addr_cnt > 0) {
+			seterrmsg("unexpected address");
+			return ERR;
+		}
+		GET_COMMAND_SUFFIX();
+		if ((garrulous = 1 - garrulous) && *errmsg)
+			fprintf(stderr, "%s\n", errmsg);
+		break;
+	case 'i':
+		if (second_addr == 0) {
+			second_addr = 1;
+		}
+		GET_COMMAND_SUFFIX();
+		if (!isglobal) clear_undo_stack();
+		if (append_lines(second_addr - 1) < 0)
+			return ERR;
+		break;
+	case 'j':
+		if (check_addr_range(current_addr, current_addr + 1) < 0)
+			return ERR;
+		GET_COMMAND_SUFFIX();
+		if (!isglobal) clear_undo_stack();
+		if (first_addr != second_addr &&
+		    join_lines(first_addr, second_addr) < 0)
+			return ERR;
+		break;
+	case 'k':
+		c = (unsigned char)*ibufp++;
+		if (second_addr == 0) {
+			seterrmsg("invalid address");
+			return ERR;
+		}
+		GET_COMMAND_SUFFIX();
+		if (mark_line_node(get_addressed_line_node(second_addr), c) < 0)
+			return ERR;
+		break;
+	case 'l':
+		if (check_addr_range(current_addr, current_addr) < 0)
+			return ERR;
+		GET_COMMAND_SUFFIX();
+		if (display_lines(first_addr, second_addr, gflag | GLS) < 0)
+			return ERR;
+		gflag = 0;
+		break;
+	case 'm':
+		if (check_addr_range(current_addr, current_addr) < 0)
+			return ERR;
+		GET_THIRD_ADDR(addr);
+		if (first_addr <= addr && addr < second_addr) {
+			seterrmsg("invalid destination");
+			return ERR;
+		}
+		GET_COMMAND_SUFFIX();
+		if (!isglobal) clear_undo_stack();
+		if (move_lines(addr) < 0)
+			return ERR;
+		break;
+	case 'n':
+		if (check_addr_range(current_addr, current_addr) < 0)
+			return ERR;
+		GET_COMMAND_SUFFIX();
+		if (display_lines(first_addr, second_addr, gflag | GNP) < 0)
+			return ERR;
+		gflag = 0;
+		break;
+	case 'p':
+		if (check_addr_range(current_addr, current_addr) < 0)
+			return ERR;
+		GET_COMMAND_SUFFIX();
+		if (display_lines(first_addr, second_addr, gflag | GPR) < 0)
+			return ERR;
+		gflag = 0;
+		break;
+	case 'P':
+		if (addr_cnt > 0) {
+			seterrmsg("unexpected address");
+			return ERR;
+		}
+		GET_COMMAND_SUFFIX();
+		prompt = prompt ? NULL : optarg ? optarg : dps;
+		break;
+	case 'q':
+	case 'Q':
+		if (addr_cnt > 0) {
+			seterrmsg("unexpected address");
+			return ERR;
+		}
+		GET_COMMAND_SUFFIX();
+		gflag =  (modified && !scripted && c == 'q') ? EMOD : EOF;
+		break;
+	case 'r':
+		if (!isspace((unsigned char)*ibufp)) {
+			seterrmsg("unexpected command suffix");
+			return ERR;
+		} else if (addr_cnt == 0)
+			second_addr = addr_last;
+		if ((fnp = get_filename(0)) == NULL)
+			return ERR;
+		GET_COMMAND_SUFFIX();
+		if (!isglobal) clear_undo_stack();
+		if ((addr = read_file(fnp, second_addr)) < 0)
+			return ERR;
+		else if (addr)
+			modified = 1;
+		break;
+	case 's':
+		do {
+			switch (*ibufp) {
+			case '\n':
+				sflags |=SGF;
+				break;
+			case 'g':
+				sflags |= SGG;
+				ibufp++;
+				break;
+			case 'p':
+				sflags |= SGP;
+				ibufp++;
+				break;
+			case 'r':
+				sflags |= SGR;
+				ibufp++;
+				break;
+			case '0': case '1': case '2': case '3': case '4':
+			case '5': case '6': case '7': case '8': case '9':
+				STRTOI(sgnum, ibufp);
+				sflags |= SGF;
+				sgflag &= ~GSG;		/* override GSG */
+				break;
+			default:
+				if (sflags) {
+					seterrmsg("invalid command suffix");
+					return ERR;
+				}
+			}
+		} while (sflags && *ibufp != '\n');
+		if (sflags && !pat) {
+			seterrmsg("no previous substitution");
+			return ERR;
+		} else if (sflags & SGG)
+			sgnum = 0;		/* override numeric arg */
+		if (*ibufp != '\n' && *(ibufp + 1) == '\n') {
+			seterrmsg("invalid pattern delimiter");
+			return ERR;
+		}
+		tpat = pat;
+		SPL1();
+		if ((!sflags || (sflags & SGR)) &&
+		    (tpat = get_compiled_pattern()) == NULL) {
+		 	SPL0();
+			return ERR;
+		} else if (tpat != pat) {
+			if (pat) {
+				regfree(pat);
+				free(pat);
+			}
+			pat = tpat;
+			patlock = 1;		/* reserve pattern */
+		}
+		SPL0();
+		if (!sflags && extract_subst_tail(&sgflag, &sgnum) < 0)
+			return ERR;
+		else if (isglobal)
+			sgflag |= GLB;
+		else
+			sgflag &= ~GLB;
+		if (sflags & SGG)
+			sgflag ^= GSG;
+		if (sflags & SGP) {
+			sgflag ^= GPR;
+			sgflag &= ~(GLS | GNP);
+		}
+		do {
+			switch (*ibufp) {
+			case 'p':
+				sgflag |= GPR;
+				ibufp++;
+				break;
+			case 'l':
+				sgflag |= GLS;
+				ibufp++;
+				break;
+			case 'n':
+				sgflag |= GNP;
+				ibufp++;
+				break;
+			default:
+				n++;
+			}
+		} while (!n);
+		if (check_addr_range(current_addr, current_addr) < 0)
+			return ERR;
+		GET_COMMAND_SUFFIX();
+		if (!isglobal) clear_undo_stack();
+		if (search_and_replace(pat, sgflag, sgnum) < 0)
+			return ERR;
+		break;
+	case 't':
+		if (check_addr_range(current_addr, current_addr) < 0)
+			return ERR;
+		GET_THIRD_ADDR(addr);
+		GET_COMMAND_SUFFIX();
+		if (!isglobal) clear_undo_stack();
+		if (copy_lines(addr) < 0)
+			return ERR;
+		break;
+	case 'u':
+		if (addr_cnt > 0) {
+			seterrmsg("unexpected address");
+			return ERR;
+		}
+		GET_COMMAND_SUFFIX();
+		if (pop_undo_stack() < 0)
+			return ERR;
+		break;
+	case 'w':
+	case 'W':
+		if ((n = *ibufp) == 'q' || n == 'Q') {
+			gflag = EOF;
+			ibufp++;
+		}
+		if (!isspace((unsigned char)*ibufp)) {
+			seterrmsg("unexpected command suffix");
+			return ERR;
+		} else if ((fnp = get_filename(0)) == NULL)
+			return ERR;
+		if (addr_cnt == 0 && !addr_last)
+			first_addr = second_addr = 0;
+		else if (check_addr_range(1, addr_last) < 0)
+			return ERR;
+		GET_COMMAND_SUFFIX();
+		if ((addr = write_file(fnp, (c == 'W') ? "a" : "w",
+		    first_addr, second_addr)) < 0)
+			return ERR;
+		else if (addr == addr_last && *fnp != '!')
+			modified = 0;
+		else if (modified && !scripted && n == 'q')
+			gflag = EMOD;
+		break;
+	case 'x':
+		if (addr_cnt > 0) {
+			seterrmsg("unexpected address");
+			return ERR;
+		}
+		GET_COMMAND_SUFFIX();
+		seterrmsg("crypt unavailable");
+		return ERR;
+	case 'z':
+		first_addr = 1;
+		if (check_addr_range(first_addr, current_addr + 1) < 0)
+			return ERR;
+		else if ('0' < *ibufp && *ibufp <= '9')
+			STRTOI(rows, ibufp);
+		GET_COMMAND_SUFFIX();
+		if (display_lines(second_addr, min(addr_last,
+		    second_addr + rows), gflag) < 0)
+			return ERR;
+		gflag = 0;
+		break;
+	case '=':
+		GET_COMMAND_SUFFIX();
+		printf("%d\n", addr_cnt ? second_addr : addr_last);
+		break;
+	case '!':
+		if (addr_cnt > 0) {
+			seterrmsg("unexpected address");
+			return ERR;
+		} else if ((sflags = get_shell_command()) < 0)
+			return ERR;
+		GET_COMMAND_SUFFIX();
+		if (sflags) printf("%s\n", shcmd + 1);
+		system(shcmd + 1);
+		if (!scripted) printf("!\n");
+		break;
+	case '\n':
+		first_addr = 1;
+		if (check_addr_range(first_addr, current_addr + 1) < 0
+		 || display_lines(second_addr, second_addr, 0) < 0)
+			return ERR;
+		break;
+	default:
+		seterrmsg("unknown command");
+		return ERR;
+	}
+	return gflag;
+}
+
+
+/* check_addr_range: return status of address range check */
+static int
+check_addr_range(int n, int m)
+{
+	if (addr_cnt == 0) {
+		first_addr = n;
+		second_addr = m;
+	}
+	if (first_addr > second_addr || 1 > first_addr ||
+	    second_addr > addr_last) {
+		seterrmsg("invalid address");
+		return ERR;
+	}
+	return 0;
+}
+
+
+/* get_matching_node_addr: return the address of the next line matching a
+   pattern in a given direction.  wrap around begin/end of editor buffer if
+   necessary */
+static int
+get_matching_node_addr(regex_t *pat, int dir)
+{
+	char *s;
+	int n = current_addr;
+	line_t *lp;
+
+	if (!pat) return ERR;
+	do {
+		if ((n = dir ? INC_MOD(n, addr_last) : DEC_MOD(n, addr_last))) {
+			lp = get_addressed_line_node(n);
+			if ((s = get_sbuf_line(lp)) == NULL)
+				return ERR;
+			if (isbinary)
+				NUL_TO_NEWLINE(s, lp->len);
+			if (!regexec(pat, s, 0, NULL, 0))
+				return n;
+		}
+	} while (n != current_addr);
+	seterrmsg("no match");
+	return  ERR;
+}
+
+
+/* get_filename: return pointer to copy of filename in the command buffer */
+static char *
+get_filename(int save)
+{
+	static char filename[PATH_MAX];
+	char *p;
+	int n;
+
+	if (*ibufp != '\n') {
+		SKIP_BLANKS();
+		if (*ibufp == '\n') {
+			seterrmsg("invalid filename");
+			return NULL;
+		} else if ((ibufp = get_extended_line(&n, 1)) == NULL)
+			return NULL;
+		else if (*ibufp == '!') {
+			ibufp++;
+			if ((n = get_shell_command()) < 0)
+				return NULL;
+			if (n) printf("%s\n", shcmd + 1);
+			return shcmd;
+		} else if (n >= PATH_MAX - 1) {
+			seterrmsg("filename too long");
+			return NULL;
+		}
+	} else {
+		if (*old_filename == '\0') {
+			seterrmsg("no current filename");
+			return  NULL;
+		}
+		return old_filename;
+	}
+
+	p = save ? old_filename : *old_filename ? filename : old_filename;
+	for (n = 0; *ibufp != '\n';)
+		p[n++] = *ibufp++;
+	p[n] = '\0';
+	return p;
+}
+
+
+/* get_shell_command: read a shell command from stdin; return substitution
+   status */
+static int
+get_shell_command(void)
+{
+	static char *buf = NULL;
+	static int n = 0;
+
+	char *s;			/* substitution char pointer */
+	int i = 0;
+	int j = 0;
+
+	if ((s = ibufp = get_extended_line(&j, 1)) == NULL)
+		return ERR;
+	REALLOC(buf, n, j + 1, ERR);
+	buf[i++] = '!';			/* prefix command w/ bang */
+	while (*ibufp != '\n')
+		switch (*ibufp) {
+		default:
+			REALLOC(buf, n, i + 2, ERR);
+			buf[i++] = *ibufp;
+			if (*ibufp++ == '\\')
+				buf[i++] = *ibufp++;
+			break;
+		case '!':
+			if (s != ibufp) {
+				REALLOC(buf, n, i + 1, ERR);
+				buf[i++] = *ibufp++;
+			}
+			else if (shcmd == NULL)
+			{
+				seterrmsg("no previous command");
+				return ERR;
+			} else {
+				REALLOC(buf, n, i + shcmdi, ERR);
+				for (s = shcmd + 1; s < shcmd + shcmdi;)
+					buf[i++] = *s++;
+				s = ibufp++;
+			}
+			break;
+		case '%':
+			if (*old_filename  == '\0') {
+				seterrmsg("no current filename");
+				return ERR;
+			}
+			j = strlen(s = strip_escapes(old_filename));
+			REALLOC(buf, n, i + j, ERR);
+			while (j--)
+				buf[i++] = *s++;
+			s = ibufp++;
+			break;
+		}
+	if (i == 1) {
+		seterrmsg("no command");
+		return ERR;
+	}
+	REALLOC(shcmd, shcmdsz, i + 1, ERR);
+	memcpy(shcmd, buf, i);
+	shcmd[shcmdi = i] = '\0';
+	return *s == '!' || *s == '%';
+}
+
+
+/* append_lines: insert text from stdin to after line n; stop when either a
+   single period is read or EOF; return status */
+static int
+append_lines(int n)
+{
+	int l;
+	char *lp = ibuf;
+	char *eot;
+	undo_t *up = NULL;
+
+	for (current_addr = n;;) {
+		if (!isglobal) {
+			if ((l = get_tty_line()) < 0)
+				return ERR;
+			else if (l == 0 || ibuf[l - 1] != '\n') {
+				clearerr(stdin);
+				return  l ? EOF : 0;
+			}
+			lp = ibuf;
+		} else if (*(lp = ibufp) == '\0')
+			return 0;
+		else {
+			while (*ibufp++ != '\n')
+				;
+			l = ibufp - lp;
+		}
+		if (l == 2 && lp[0] == '.' && lp[1] == '\n') {
+			return 0;
+		}
+		eot = lp + l;
+		SPL1();
+		do {
+			if ((lp = put_sbuf_line(lp)) == NULL) {
+				SPL0();
+				return ERR;
+			} else if (up)
+				up->t = get_addressed_line_node(current_addr);
+			else if ((up = push_undo_stack(UADD, current_addr,
+			    current_addr)) == NULL) {
+				SPL0();
+				return ERR;
+			}
+		} while (lp != eot);
+		modified = 1;
+		SPL0();
+	}
+	/* NOTREACHED */
+}
+
+
+/* join_lines: replace a range of lines with the joined text of those lines */
+static int
+join_lines(int from, int to)
+{
+	static char *buf = NULL;
+	static int n;
+
+	char *s;
+	int size = 0;
+	line_t *bp, *ep;
+
+	ep = get_addressed_line_node(INC_MOD(to, addr_last));
+	bp = get_addressed_line_node(from);
+	for (; bp != ep; bp = bp->q_forw) {
+		if ((s = get_sbuf_line(bp)) == NULL)
+			return ERR;
+		REALLOC(buf, n, size + bp->len, ERR);
+		memcpy(buf + size, s, bp->len);
+		size += bp->len;
+	}
+	REALLOC(buf, n, size + 2, ERR);
+	memcpy(buf + size, "\n", 2);
+	if (delete_lines(from, to) < 0)
+		return ERR;
+	current_addr = from - 1;
+	SPL1();
+	if (put_sbuf_line(buf) == NULL ||
+	    push_undo_stack(UADD, current_addr, current_addr) == NULL) {
+		SPL0();
+		return ERR;
+	}
+	modified = 1;
+	SPL0();
+	return 0;
+}
+
+
+/* move_lines: move a range of lines */
+static int
+move_lines(int addr)
+{
+	line_t *b1, *a1, *b2, *a2;
+	int n = INC_MOD(second_addr, addr_last);
+	int p = first_addr - 1;
+	int done = (addr == first_addr - 1 || addr == second_addr);
+
+	SPL1();
+	if (done) {
+		a2 = get_addressed_line_node(n);
+		b2 = get_addressed_line_node(p);
+		current_addr = second_addr;
+	} else if (push_undo_stack(UMOV, p, n) == NULL ||
+	    push_undo_stack(UMOV, addr, INC_MOD(addr, addr_last)) == NULL) {
+		SPL0();
+		return ERR;
+	} else {
+		a1 = get_addressed_line_node(n);
+		if (addr < first_addr) {
+			b1 = get_addressed_line_node(p);
+			b2 = get_addressed_line_node(addr);
+					/* this get_addressed_line_node last! */
+		} else {
+			b2 = get_addressed_line_node(addr);
+			b1 = get_addressed_line_node(p);
+					/* this get_addressed_line_node last! */
+		}
+		a2 = b2->q_forw;
+		REQUE(b2, b1->q_forw);
+		REQUE(a1->q_back, a2);
+		REQUE(b1, a1);
+		current_addr = addr + ((addr < first_addr) ?
+		    second_addr - first_addr + 1 : 0);
+	}
+	if (isglobal)
+		unset_active_nodes(b2->q_forw, a2);
+	modified = 1;
+	SPL0();
+	return 0;
+}
+
+
+/* copy_lines: copy a range of lines; return status */
+static int
+copy_lines(int addr)
+{
+	line_t *lp, *np = get_addressed_line_node(first_addr);
+	undo_t *up = NULL;
+	int n = second_addr - first_addr + 1;
+	int m = 0;
+
+	current_addr = addr;
+	if (first_addr <= addr && addr < second_addr) {
+		n =  addr - first_addr + 1;
+		m = second_addr - addr;
+	}
+	for (; n > 0; n=m, m=0, np = get_addressed_line_node(current_addr + 1))
+		for (; n-- > 0; np = np->q_forw) {
+			SPL1();
+			if ((lp = dup_line_node(np)) == NULL) {
+				SPL0();
+				return ERR;
+			}
+			add_line_node(lp);
+			if (up)
+				up->t = lp;
+			else if ((up = push_undo_stack(UADD, current_addr,
+			    current_addr)) == NULL) {
+				SPL0();
+				return ERR;
+			}
+			modified = 1;
+			SPL0();
+		}
+	return 0;
+}
+
+
+/* delete_lines: delete a range of lines */
+int
+delete_lines(int from, int to)
+{
+	line_t *n, *p;
+
+	SPL1();
+	if (push_undo_stack(UDEL, from, to) == NULL) {
+		SPL0();
+		return ERR;
+	}
+	n = get_addressed_line_node(INC_MOD(to, addr_last));
+	p = get_addressed_line_node(from - 1);
+					/* this get_addressed_line_node last! */
+	if (isglobal)
+		unset_active_nodes(p->q_forw, n);
+	REQUE(p, n);
+	addr_last -= to - from + 1;
+	current_addr = from - 1;
+	modified = 1;
+	SPL0();
+	return 0;
+}
+
+
+/* display_lines: print a range of lines to stdout */
+int
+display_lines(int from, int to, int gflag)
+{
+	line_t *bp;
+	line_t *ep;
+	char *s;
+
+	if (!from) {
+		seterrmsg("invalid address");
+		return ERR;
+	}
+	ep = get_addressed_line_node(INC_MOD(to, addr_last));
+	bp = get_addressed_line_node(from);
+	for (; bp != ep; bp = bp->q_forw) {
+		if ((s = get_sbuf_line(bp)) == NULL)
+			return ERR;
+		if (put_tty_line(s, bp->len, current_addr = from++, gflag) < 0)
+			return ERR;
+	}
+	return 0;
+}
+
+
+#define MAXMARK 26			/* max number of marks */
+
+static line_t *mark[MAXMARK];		/* line markers */
+static int markno;			/* line marker count */
+
+/* mark_line_node: set a line node mark */
+static int
+mark_line_node(line_t *lp, int n)
+{
+	if (!islower(n)) {
+		seterrmsg("invalid mark character");
+		return ERR;
+	} else if (mark[n - 'a'] == NULL)
+		markno++;
+	mark[n - 'a'] = lp;
+	return 0;
+}
+
+
+/* get_marked_node_addr: return address of a marked line */
+static int
+get_marked_node_addr(int n)
+{
+	if (!islower(n)) {
+		seterrmsg("invalid mark character");
+		return ERR;
+	}
+	return get_line_node_addr(mark[n - 'a']);
+}
+
+
+/* unmark_line_node: clear line node mark */
+void
+unmark_line_node(line_t *lp)
+{
+	int i;
+
+	for (i = 0; markno && i < MAXMARK; i++)
+		if (mark[i] == lp) {
+			mark[i] = NULL;
+			markno--;
+		}
+}
+
+
+/* dup_line_node: return a pointer to a copy of a line node */
+static line_t *
+dup_line_node(line_t *lp)
+{
+	line_t *np;
+
+	if ((np = malloc(sizeof(line_t))) == NULL) {
+		perror(NULL);
+		seterrmsg("out of memory");
+		return NULL;
+	}
+	np->seek = lp->seek;
+	np->len = lp->len;
+	return np;
+}
+
+
+/* has_trailing_escape:  return the parity of escapes preceding a character
+   in a string */
+int
+has_trailing_escape(char *s, char *t)
+{
+    return (s == t || *(t - 1) != '\\') ? 0 : !has_trailing_escape(s, t - 1);
+}
+
+
+/* strip_escapes: return copy of escaped string of at most length PATH_MAX */
+char *
+strip_escapes(char *s)
+{
+	static char *file = NULL;
+	static int filesz = 0;
+
+	int i = 0;
+
+	REALLOC(file, filesz, PATH_MAX, NULL);
+	/* assert: no trailing escape */
+	while ((file[i++] = (*s == '\\') ? *++s : *s) != '\0' &&
+	       i < PATH_MAX-1)
+		s++;
+	file[PATH_MAX-1] = '\0';
+	return file;
+}
+
+
+void
+signal_hup(int signo)
+{
+	int save_errno = errno;
+
+	if (mutex)
+		sighup = 1;
+	else
+		handle_hup(signo);
+	errno = save_errno;
+}
+
+
+void
+signal_int(int signo)
+{
+	int save_errno = errno;
+
+	if (mutex)
+		sigint = 1;
+	else
+		handle_int(signo);
+	errno = save_errno;
+}
+
+
+void
+handle_hup(int signo)
+{
+	char hup[PATH_MAX];
+
+	if (!sigactive)
+		quit(1);		/* XXX signal race */
+	sighup = 0;
+	/* XXX signal race */
+	if (addr_last && write_file("ed.hup", "w", 1, addr_last) < 0 &&
+	    home != NULL && home[0] == '/') {
+		if (strlcpy(hup, home, sizeof(hup)) < sizeof(hup) &&
+		    strlcat(hup, "/ed.hup", sizeof(hup)) < sizeof(hup))
+			write_file(hup, "w", 1, addr_last);
+	}
+	_exit(2);
+}
+
+
+void
+handle_int(int signo)
+{
+	if (!sigactive)
+		_exit(1);
+	sigint = 0;
+	siglongjmp(env, -1);
+}
+
+
+void
+handle_winch(int signo)
+{
+	int save_errno = errno;
+	struct winsize ws;		/* window size structure */
+
+	if (ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) == 0) {
+		if (ws.ws_row > 2)
+			rows = ws.ws_row - 2;
+		if (ws.ws_col > 8)
+			cols = ws.ws_col - 8;
+	}
+	errno = save_errno;
+}
diff --git a/bin/ed/re.c b/bin/ed/re.c
new file mode 100644
index 0000000..c81a3ee
--- /dev/null
+++ b/bin/ed/re.c
@@ -0,0 +1,139 @@
+/*	$OpenBSD: re.c,v 1.19 2018/06/19 12:36:18 martijn Exp $	*/
+/*	$NetBSD: re.c,v 1.14 1995/03/21 09:04:48 cgd Exp $	*/
+
+/* re.c: This file contains the regular expression interface routines for
+   the ed line editor. */
+/*-
+ * Copyright (c) 1993 Andrew Moore, Talke Studio.
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+ */
+
+#include <regex.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "ed.h"
+
+static char *extract_pattern(int);
+static char *parse_char_class(char *);
+
+extern int patlock;
+
+
+/* get_compiled_pattern: return pointer to compiled pattern from command
+   buffer */
+regex_t *
+get_compiled_pattern(void)
+{
+	static regex_t *exp = NULL;
+	char errbuf[128] = "";
+
+	char *exps;
+	char delimiter;
+	int n;
+
+	if ((delimiter = *ibufp) == ' ') {
+		seterrmsg("invalid pattern delimiter");
+		return NULL;
+	} else if (delimiter == '\n' || *++ibufp == '\n' || *ibufp == delimiter) {
+		if (!exp)
+			seterrmsg("no previous pattern");
+		return exp;
+	} else if ((exps = extract_pattern(delimiter)) == NULL)
+		return NULL;
+	/* buffer alloc'd && not reserved */
+	if (exp && !patlock)
+		regfree(exp);
+	else if ((exp = malloc(sizeof(regex_t))) == NULL) {
+		perror(NULL);
+		seterrmsg("out of memory");
+		return NULL;
+	}
+	patlock = 0;
+	if ((n = regcomp(exp, exps, 0)) != 0) {
+		regerror(n, exp, errbuf, sizeof errbuf);
+		seterrmsg(errbuf);
+		free(exp);
+		return exp = NULL;
+	}
+	return exp;
+}
+
+
+/* extract_pattern: copy a pattern string from the command buffer; return
+   pointer to the copy */
+static char *
+extract_pattern(int delimiter)
+{
+	static char *lhbuf = NULL;	/* buffer */
+	static int lhbufsz = 0;		/* buffer size */
+
+	char *nd;
+	int len;
+
+	for (nd = ibufp; *nd != delimiter && *nd != '\n'; nd++)
+		switch (*nd) {
+		default:
+			break;
+		case '[':
+			if ((nd = parse_char_class(++nd)) == NULL) {
+				seterrmsg("unbalanced brackets ([])");
+				return NULL;
+			}
+			break;
+		case '\\':
+			if (*++nd == '\n') {
+				seterrmsg("trailing backslash (\\)");
+				return NULL;
+			}
+			break;
+		}
+	len = nd - ibufp;
+	REALLOC(lhbuf, lhbufsz, len + 1, NULL);
+	memcpy(lhbuf, ibufp, len);
+	lhbuf[len] = '\0';
+	ibufp = nd;
+	return (isbinary) ? NUL_TO_NEWLINE(lhbuf, len) : lhbuf;
+}
+
+
+/* parse_char_class: expand a POSIX character class */
+static char *
+parse_char_class(char *s)
+{
+	int c, d;
+
+	if (*s == '^')
+		s++;
+	if (*s == ']')
+		s++;
+	for (; *s != ']' && *s != '\n'; s++)
+		if (*s == '[' && ((d = *(s+1)) == '.' || d == ':' || d == '='))
+			for (s++, c = *++s; *s != ']' || c != d; s++)
+				if ((c = *s) == '\n')
+					return NULL;
+	return  (*s == ']') ? s : NULL;
+}
diff --git a/bin/ed/sub.c b/bin/ed/sub.c
new file mode 100644
index 0000000..f920d9d
--- /dev/null
+++ b/bin/ed/sub.c
@@ -0,0 +1,272 @@
+/*	$OpenBSD: sub.c,v 1.18 2016/10/11 06:54:05 martijn Exp $	*/
+/*	$NetBSD: sub.c,v 1.4 1995/03/21 09:04:50 cgd Exp $	*/
+
+/* sub.c: This file contains the substitution routines for the ed
+   line editor */
+/*-
+ * Copyright (c) 1993 Andrew Moore, Talke Studio.
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+ */
+
+#include <limits.h>
+#include <regex.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#ifndef REG_STARTEND
+#define REG_STARTEND 0004
+#endif
+
+#include "ed.h"
+
+static char *extract_subst_template(void);
+static int substitute_matching_text(regex_t *, line_t *, int, int);
+static int apply_subst_template(char *, regmatch_t *, int, int);
+
+static char *rhbuf;		/* rhs substitution buffer */
+static int rhbufsz;		/* rhs substitution buffer size */
+static int rhbufi;		/* rhs substitution buffer index */
+
+/* extract_subst_tail: extract substitution tail from the command buffer */
+int
+extract_subst_tail(int *flagp, int *np)
+{
+	char delimiter;
+
+	*flagp = *np = 0;
+	if ((delimiter = *ibufp) == '\n') {
+		rhbufi = 0;
+		*flagp = GPR;
+		return 0;
+	} else if (extract_subst_template() == NULL)
+		return  ERR;
+	else if (*ibufp == '\n') {
+		*flagp = GPR;
+		return 0;
+	} else if (*ibufp == delimiter)
+		ibufp++;
+	if ('1' <= *ibufp && *ibufp <= '9') {
+		STRTOI(*np, ibufp);
+		return 0;
+	} else if (*ibufp == 'g') {
+		ibufp++;
+		*flagp = GSG;
+		return 0;
+	}
+	return 0;
+}
+
+
+/* extract_subst_template: return pointer to copy of substitution template
+   in the command buffer */
+static char *
+extract_subst_template(void)
+{
+	int n = 0;
+	int i = 0;
+	char c;
+	char delimiter = *ibufp++;
+
+	if (*ibufp == '%' && *(ibufp + 1) == delimiter) {
+		ibufp++;
+		if (!rhbuf)
+			seterrmsg("no previous substitution");
+		return rhbuf;
+	}
+	while (*ibufp != delimiter) {
+		REALLOC(rhbuf, rhbufsz, i + 2, NULL);
+		if ((c = rhbuf[i++] = *ibufp++) == '\n' && *ibufp == '\0') {
+			i--, ibufp--;
+			break;
+		} else if (c != '\\')
+			;
+		else if ((rhbuf[i++] = *ibufp++) != '\n')
+			;
+		else if (!isglobal) {
+			while ((n = get_tty_line()) == 0 ||
+			    (n > 0 && ibuf[n - 1] != '\n'))
+				clearerr(stdin);
+			if (n < 0)
+				return NULL;
+		}
+	}
+	REALLOC(rhbuf, rhbufsz, i + 1, NULL);
+	rhbuf[rhbufi = i] = '\0';
+	return  rhbuf;
+}
+
+
+static char *rbuf;		/* substitute_matching_text buffer */
+static int rbufsz;		/* substitute_matching_text buffer size */
+
+/* search_and_replace: for each line in a range, change text matching a pattern
+   according to a substitution template; return status  */
+int
+search_and_replace(regex_t *pat, int gflag, int kth)
+{
+	undo_t *up;
+	char *txt;
+	char *eot;
+	int lc;
+	int xa = current_addr;
+	int nsubs = 0;
+	line_t *lp;
+	int len;
+
+	current_addr = first_addr - 1;
+	for (lc = 0; lc <= second_addr - first_addr; lc++) {
+		lp = get_addressed_line_node(++current_addr);
+		if ((len = substitute_matching_text(pat, lp, gflag, kth)) < 0)
+			return ERR;
+		else if (len) {
+			up = NULL;
+			if (delete_lines(current_addr, current_addr) < 0)
+				return ERR;
+			txt = rbuf;
+			eot = rbuf + len;
+			SPL1();
+			do {
+				if ((txt = put_sbuf_line(txt)) == NULL) {
+					SPL0();
+					return ERR;
+				} else if (up)
+					up->t = get_addressed_line_node(current_addr);
+				else if ((up = push_undo_stack(UADD,
+				    current_addr, current_addr)) == NULL) {
+					SPL0();
+					return ERR;
+				}
+			} while (txt != eot);
+			SPL0();
+			nsubs++;
+			xa = current_addr;
+		}
+	}
+	current_addr = xa;
+	if  (nsubs == 0 && !(gflag & GLB)) {
+		seterrmsg("no match");
+		return ERR;
+	} else if ((gflag & (GPR | GLS | GNP)) &&
+	    display_lines(current_addr, current_addr, gflag) < 0)
+		return ERR;
+	return 0;
+}
+
+
+/* substitute_matching_text: replace text matched by a pattern according to
+   a substitution template; return length of rbuf if changed, 0 if unchanged, or
+   ERR on error */
+static int
+substitute_matching_text(regex_t *pat, line_t *lp, int gflag, int kth)
+{
+	int off = 0;
+	int changed = 0;
+	int matchno = 0;
+	int i = 0;
+	int nempty = -1;
+	regmatch_t rm[SE_MAX];
+	char *txt;
+	char *eot, *eom;
+
+	if ((eom = txt = get_sbuf_line(lp)) == NULL)
+		return ERR;
+	if (isbinary)
+		NUL_TO_NEWLINE(txt, lp->len);
+	eot = txt + lp->len;
+	if (!regexec(pat, txt, SE_MAX, rm, 0)) {
+		do {
+/* Don't do a 0-length match directly after a non-0-length */
+			if (rm[0].rm_eo == nempty) {
+				rm[0].rm_so++;
+				rm[0].rm_eo = lp->len;
+				continue;
+			}
+			if (!kth || kth == ++matchno) {
+				changed = 1;
+				i = rm[0].rm_so - (eom - txt);
+				REALLOC(rbuf, rbufsz, off + i, ERR);
+				if (isbinary)
+					NEWLINE_TO_NUL(eom,
+					    rm[0].rm_eo - (eom - txt));
+				memcpy(rbuf + off, eom, i);
+				off += i;
+				if ((off = apply_subst_template(txt, rm, off,
+				    pat->re_nsub)) < 0)
+					return ERR;
+				eom = txt + rm[0].rm_eo;
+				if (kth)
+					break;
+			}
+			if (rm[0].rm_so == rm[0].rm_eo)
+				rm[0].rm_so = rm[0].rm_eo + 1;
+			else
+				nempty = rm[0].rm_so = rm[0].rm_eo;
+			rm[0].rm_eo = lp->len;
+		} while (rm[0].rm_so < lp->len && (gflag & GSG || kth) &&
+		    !regexec(pat, txt, SE_MAX, rm, REG_STARTEND | REG_NOTBOL));
+		i = eot - eom;
+		REALLOC(rbuf, rbufsz, off + i + 2, ERR);
+		if (isbinary)
+			NEWLINE_TO_NUL(eom, i);
+		memcpy(rbuf + off, eom, i);
+		memcpy(rbuf + off + i, "\n", 2);
+	}
+	return changed ? off + i + 1 : 0;
+}
+
+
+/* apply_subst_template: modify text according to a substitution template;
+   return offset to end of modified text */
+static int
+apply_subst_template(char *boln, regmatch_t *rm, int off, int re_nsub)
+{
+	int j = 0;
+	int k = 0;
+	int n;
+	char *sub = rhbuf;
+
+	for (; sub - rhbuf < rhbufi; sub++)
+		if (*sub == '&') {
+			j = rm[0].rm_so;
+			k = rm[0].rm_eo;
+			REALLOC(rbuf, rbufsz, off + k - j, ERR);
+			while (j < k)
+				rbuf[off++] = boln[j++];
+		} else if (*sub == '\\' && '1' <= *++sub && *sub <= '9' &&
+		    (n = *sub - '0') <= re_nsub) {
+			j = rm[n].rm_so;
+			k = rm[n].rm_eo;
+			REALLOC(rbuf, rbufsz, off + k - j, ERR);
+			while (j < k)
+				rbuf[off++] = boln[j++];
+		} else {
+			REALLOC(rbuf, rbufsz, off + 1, ERR);
+			rbuf[off++] = *sub;
+		}
+	REALLOC(rbuf, rbufsz, off + 1, ERR);
+	rbuf[off] = '\0';
+	return off;
+}
diff --git a/bin/ed/undo.c b/bin/ed/undo.c
new file mode 100644
index 0000000..4291be0
--- /dev/null
+++ b/bin/ed/undo.c
@@ -0,0 +1,146 @@
+/*	$OpenBSD: undo.c,v 1.14 2016/03/22 17:58:28 mmcc Exp $	*/
+/*	$NetBSD: undo.c,v 1.2 1995/03/21 09:04:52 cgd Exp $	*/
+
+/* undo.c: This file contains the undo routines for the ed line editor */
+/*-
+ * Copyright (c) 1993 Andrew Moore, Talke Studio.
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+ */
+
+#include <regex.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "ed.h"
+
+#define USIZE 100				/* undo stack size */
+static undo_t *ustack = NULL;			/* undo stack */
+static int usize = 0;				/* stack size variable */
+static int u_p = 0;				/* undo stack pointer */
+
+/* push_undo_stack: return pointer to initialized undo node */
+undo_t *
+push_undo_stack(int type, int from, int to)
+{
+	undo_t *t;
+
+	t = ustack;
+	if (u_p < usize ||
+	    (t = reallocarray(ustack, (usize += USIZE), sizeof(undo_t))) != NULL) {
+		ustack = t;
+		ustack[u_p].type = type;
+		ustack[u_p].t = get_addressed_line_node(to);
+		ustack[u_p].h = get_addressed_line_node(from);
+		return ustack + u_p++;
+	}
+	/* out of memory - release undo stack */
+	perror(NULL);
+	seterrmsg("out of memory");
+	clear_undo_stack();
+	free(ustack);
+	ustack = NULL;
+	usize = 0;
+	return NULL;
+}
+
+
+/* USWAP: swap undo nodes */
+#define USWAP(x,y) { \
+	undo_t utmp; \
+	utmp = x, x = y, y = utmp; \
+}
+
+
+int u_current_addr = -1;	/* if >= 0, undo enabled */
+int u_addr_last = -1;		/* if >= 0, undo enabled */
+
+/* pop_undo_stack: undo last change to the editor buffer */
+int
+pop_undo_stack(void)
+{
+	int n;
+	int o_current_addr = current_addr;
+	int o_addr_last = addr_last;
+
+	if (u_current_addr == -1 || u_addr_last == -1) {
+		seterrmsg("nothing to undo");
+		return ERR;
+	} else if (u_p)
+		modified = 1;
+	get_addressed_line_node(0);	/* this get_addressed_line_node last! */
+	SPL1();
+	for (n = u_p; n-- > 0;) {
+		switch(ustack[n].type) {
+		case UADD:
+			REQUE(ustack[n].h->q_back, ustack[n].t->q_forw);
+			break;
+		case UDEL:
+			REQUE(ustack[n].h->q_back, ustack[n].h);
+			REQUE(ustack[n].t, ustack[n].t->q_forw);
+			break;
+		case UMOV:
+		case VMOV:
+			REQUE(ustack[n - 1].h, ustack[n].h->q_forw);
+			REQUE(ustack[n].t->q_back, ustack[n - 1].t);
+			REQUE(ustack[n].h, ustack[n].t);
+			n--;
+			break;
+		default:
+			/*NOTREACHED*/
+			;
+		}
+		ustack[n].type ^= 1;
+	}
+	/* reverse undo stack order */
+	for (n = u_p; n-- > (u_p + 1)/ 2;)
+		USWAP(ustack[n], ustack[u_p - 1 - n]);
+	if (isglobal)
+		clear_active_list();
+	current_addr = u_current_addr, u_current_addr = o_current_addr;
+	addr_last = u_addr_last, u_addr_last = o_addr_last;
+	SPL0();
+	return 0;
+}
+
+
+/* clear_undo_stack: clear the undo stack */
+void
+clear_undo_stack(void)
+{
+	line_t *lp, *ep, *tl;
+
+	while (u_p--)
+		if (ustack[u_p].type == UDEL) {
+			ep = ustack[u_p].t->q_forw;
+			for (lp = ustack[u_p].h; lp != ep; lp = tl) {
+				unmark_line_node(lp);
+				tl = lp->q_forw;
+				free(lp);
+			}
+		}
+	u_p = 0;
+	u_current_addr = current_addr;
+	u_addr_last = addr_last;
+}