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 /dev/stdout
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 recognized; 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(7). 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 replaced. 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 expression (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 constructed 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 expression. 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 indicated number of
lines. The plus sign may be omitted.
- 8.
- An address followed by (or followed by a regular expression enclosed in
slashes specifies the first matching line following (or preceding) that
address. The search wraps around if necessary. 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 characters 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
require no addresses regard the presence of an address as an error. Commands
which accept one or two addresses assume default addresses when insufficient
are given. If more addresses are given than a command requires, 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 (default) 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 filename 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
regularexpression. 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 newlines 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 characters as a backslash,
an and four hexadecimal digits. Long lines are folded, with the second and
subsequent sub-lines indented 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 current 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 modified 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 replacement 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 expression/replacement/p.
The second may be omitted if the replacement 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 parenthesized
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 prefixing 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 interpreted
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 equivalent 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 after the last newline.