term% cat index.txt ED(1) General Commands Manual ED(1)
NAME
ed - text editor
SYNOPSIS
ed [ - ] [ -o ] [ file ]
DESCRIPTION
Ed is a venerable text editor.
If a file argument is given, ed simulates an command (see below) on
that file: it is read into ed's buffer so that it can be edited. The
options are
- Suppress the printing of character counts by and commands and of
the confirming by commands.
-o (for output piping) Write all output to the standard error file
except writing by commands. If no file is given, make /fd/1 the
remembered file; see the command below.
Ed operates on a `buffer', a copy of the file it is editing; changes
made in the buffer have no effect on the file until a (write) command
is given. The copy of the text being edited resides in a temporary
file called the buffer.
Commands to ed have a simple and regular structure: zero, one, or two
addresses followed by a single character command, possibly followed by
parameters to the command. These addresses specify one or more lines
in the buffer. Missing addresses are supplied by default.
In general, only one command may appear on a line. Certain commands
allow the addition of text to the buffer. While ed is accepting text,
it is said to be in input mode. In this mode, no commands are recog‐
nized; all input is merely collected. Input mode is left by typing a
period alone at the beginning of a line.
Ed supports the regular expression notation described in regexp(6).
Regular expressions are used in addresses to specify lines and in one
command (see s below) to specify a portion of a line which is to be re‐
placed. If it is desired to use one of the regular expression
metacharacters as an ordinary character, that character may be preceded
by `\'. This also applies to the character bounding the regular ex‐
pression (often and to itself.
To understand addressing in ed it is necessary to know that at any time
there is a current line. Generally, the current line is the last line
affected by a command; however, the exact effect on the current line is
discussed under the description of each command. Addresses are con‐
structed as follows.
1. The character customarily called `dot', addresses the current
line.
2. The character addresses the last line of the buffer.
3. A decimal number n addresses the n-th line of the buffer.
4. 'x addresses the line marked with the name x, which must be a
lower-case letter. Lines are marked with the command.
5. A regular expression enclosed in slashes ( addresses the line
found by searching forward from the current line and stopping at
the first line containing a string that matches the regular ex‐
pression. If necessary the search wraps around to the beginning
of the buffer.
6. A regular expression enclosed in queries addresses the line
found by searching backward from the current line and stopping
at the first line containing a string that matches the regular
expression. If necessary the search wraps around to the end of
the buffer.
7. An address followed by a plus sign or a minus sign followed by a
decimal number specifies that address plus (resp. minus) the in‐
dicated number of lines. The plus sign may be omitted.
8. An address followed by (or followed by a regular expression en‐
closed in slashes specifies the first matching line following
(or preceding) that address. The search wraps around if neces‐
sary. The may be omitted, so addresses the first line in the
buffer with an Enclosing the regular expression in reverses the
search direction.
9. If an address begins with or the addition or subtraction is
taken with respect to the current line; e.g. is understood to
mean
10. If an address ends with or then 1 is added (resp. subtracted).
As a consequence of this rule and rule 9, the address refers to
the line before the current line. Moreover, trailing and char‐
acters have cumulative effect, so refers to the current line
less 2.
11. To maintain compatibility with earlier versions of the editor,
the character in addresses is equivalent to
Commands may require zero, one, or two addresses. Commands which re‐
quire no addresses regard the presence of an address as an error. Com‐
mands which accept one or two addresses assume default addresses when
insufficient are given. If more addresses are given than a command re‐
quires, the last one or two (depending on what is accepted) are used.
Addresses are separated from each other typically by a comma They may
also be separated by a semicolon In this case the current line is set
to the previous address before the next address is interpreted. If no
address precedes a comma or semicolon, line 1 is assumed; if no address
follows, the last line of the buffer is assumed. The second address of
any two-address sequence must correspond to a line following the line
corresponding to the first address.
In the following list of ed commands, the default addresses are shown
in parentheses. The parentheses are not part of the address, but are
used to show that the given addresses are the default. `Dot' means the
current line.
(.)a
<text>
. Read the given text and append it after the addressed line. Dot
is left on the last line input, if there were any, otherwise at
the addressed line. Address is legal for this command; text is
placed at the beginning of the buffer.
(.,.)b[+-][pagesize][pln]
Browse. Print a `page', normally 20 lines. The optional (de‐
fault) or specifies whether the next or previous page is to be
printed. The optional pagesize is the number of lines in a
page. The optional or causes printing in the specified format,
initially Pagesize and format are remembered between commands.
Dot is left at the last line displayed.
(.,.)c
<text>
. Change. Delete the addressed lines, then accept input text to
replace these lines. Dot is left at the last line input; if
there were none, it is left at the line preceding the deleted
lines.
(.,.)d Delete the addressed lines from the buffer. Dot is set to the
line following the last line deleted, or to the last line of the
buffer if the deleted lines had no successor.
e filename
Edit. Delete the entire contents of the buffer; then read the
named file into the buffer. Dot is set to the last line of the
buffer. The number of characters read is typed. The file name
is remembered for possible use in later or commands. If file‐
name is missing, the remembered name is used.
E filename
Unconditional see below.
f filename
Print the currently remembered file name. If filename is given,
the currently remembered file name is first changed to filename.
(1,$)g/regular expression/command list
(1,$)g/regular expression/
(1,$)g/regular expression
Global. First mark every line which matches the given regular‐
expression. Then for every such line, execute the command list
with dot initially set to that line. A single command or the
first of multiple commands appears on the same line with the
global command. All lines of a multi-line list except the last
line must end with The `.' terminating input mode for an command
may be omitted if it would be on the last line of the command
list. The commands and are not permitted in the command list.
Any character other than space or newline may be used instead of
to delimit the regular expression. The second and third forms
mean g/regular expression/p.
(.)i
<text>
. Insert the given text before the addressed line. Dot is left at
the last line input, or, if there were none, at the line before
the addressed line. This command differs from the a command
only in the placement of the text.
(.,.+1)j
Join the addressed lines into a single line; intermediate new‐
lines are deleted. Dot is left at the resulting line.
(.)kx Mark the addressed line with name x, which must be a lower-case
letter. The address form 'x then addresses this line.
(.,.)l List. Print the addressed lines in an unambiguous way: a tab is
printed as a backspace as backslashes as and non-printing char‐
acters as a backslash, an and four hexadecimal digits. Long
lines are folded, with the second and subsequent sub-lines in‐
dented one tab stop. If the last character in the line is a
blank, it is followed by An may be appended, like to any non-I/O
command.
(.,.)ma
Move. Reposition the addressed lines after the line addressed
by a. Dot is left at the last moved line.
(.,.)n Number. Perform prefixing each line with its line number and a
tab. An may be appended, like to any non-I/O command.
(.,.)p Print the addressed lines. Dot is left at the last line
printed. A appended to any non-I/O command causes the then cur‐
rent line to be printed after the command is executed.
(.,.)P This command is a synonym for
q Quit the editor. No automatic write of a file is done. A or
command is considered to be in error if the buffer has been mod‐
ified since the last or command.
Q Quit unconditionally.
($)r filename
Read in the given file after the addressed line. If no filename
is given, the remembered file name is used. The file name is
remembered if there were no remembered file name already. If
the read is successful, the number of characters read is
printed. Dot is left at the last line read from the file.
(.,.)sn/regular expression/replacement/
(.,.)sn/regular expression/replacement/g
(.,.)sn/regular expression/replacement
Substitute. Search each addressed line for an occurrence of the
specified regular expression. On each line in which n matches
are found (n defaults to 1 if missing), the nth matched string
is replaced by the replacement specified. If the global re‐
placement indicator appears after the command, all subsequent
matches on the line are also replaced. It is an error for the
substitution to fail on all addressed lines. Any character
other than space or newline may be used instead of to delimit
the regular expression and the replacement. Dot is left at the
last line substituted. The third form means sn/regular expres‐
sion/replacement/p. The second may be omitted if the replace‐
ment is empty.
An ampersand appearing in the replacement is replaced by the
string matching the regular expression. The characters \n,
where n is a digit, are replaced by the text matched by the n-th
regular subexpression enclosed between and When nested parenthe‐
sized subexpressions are present, n is determined by counting
occurrences of starting from the left.
A literal or newline may be included in a replacement by prefix‐
ing it with
(.,.)ta
Transfer. Copy the addressed lines after the line addressed by
a. Dot is left at the last line of the copy.
(.,.)u Undo. Restore the preceding contents of the first addressed
line (sic), which must be the last line in which a substitution
was made (double sic).
(1,$)v/regular expression/command list
This command is the same as the global command except that the
command list is executed with dot initially set to every line
except those matching the regular expression.
(1,$)w filename
Write the addressed lines to the given file. If the file does
not exist, it is created with mode 666 (readable and writable by
everyone). If no filename is given, the remembered file name,
if any, is used. The file name is remembered if there were no
remembered file name already. Dot is unchanged. If the write
is successful, the number of characters written is printed.
(1,$)W filename
Perform but append to, instead of overwriting, any existing file
contents.
($)= Print the line number of the addressed line. Dot is unchanged.
!shell command
Send the remainder of the line after the to rc(1) to be inter‐
preted as a command. Dot is unchanged.
(.+1)<newline>
An address without a command is taken as a command. A terminal
may be omitted from the address. A blank line alone is equiva‐
lent to it is useful for stepping through text.
If an interrupt signal (DEL) is sent, ed prints a and returns to its
command level.
When reading a file, ed discards NUL characters and all characters af‐
ter the last newline.
FILES
/tmp/e*
ed.hup work is saved here if terminal hangs up
SOURCE
/sys/src/cmd/ed.c
SEE ALSO
sam(1), sed(1), regexp(6)
DIAGNOSTICS
?name for inaccessible file; for temporary file overflow; for errors in
commands or other overflows.
ED(1)