Manual Pages for UNIX Darwin command on man ed

ED(1) ED(1)

NAME

ed - text editor

SYNOPSIS

ed [-] [-sx] [-p string] [file]

DESCRIPTION

eedd is a line-oriented text editor. It is used to create, display, mod-

ify and otherwise manipulate text files.

If invoked with a file argument, then a copy of file is read into the

editor's buffer. Changes are made to this copy and not directly to

file itself. Upon quitting eedd, any changes not explicitly saved with

a `w' command are lost. Editing is done in two distinct modes: command and input. When first

invoked, eedd is in command mode. In this mode commands are read from

the standard input and executed to manipulate the contents of the edi-

tor buffer. A typical command might look like: ,s/old/new/g which replaces all occurrences of the string old with new. When an input command, such as `a' (append), `i' (insert) or `c'

(change), is given, eedd 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 (.) on a line.

All eedd commands operate on whole lines or ranges of lines; e.g., the

`d' command deletes lines; the `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 `s' command is applied

to whole lines at a time.

In general, eedd commands consist of zero or more line addresses, fol-

lowed by a single character command and possibly additional parameters;

i.e., commands have the structure: [address [,address]]command[parameters]

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.

OOPPTTIIOONNSS

-s Suppresses diagnostics. This should be used if eedd's standard

input is from a script.

-x Prompts for an encryption key to be used in subsequent reads

and writes (see the `x' command).

-p string

Specifies a command prompt. This may be toggled on and off

with the `P' command.

file Specifies the name of a file to read. If file is prefixed with

a bang (!), then it is interpreted as a shell command. In this

case, what is read is the standard output of file executed via

sh(1). To read a file whose name begins with a bang, prefix the name with a backslash (\). The default filename is set to

file only if it is not prefixed with a bang.

LLIINNEE AADDDDRREESSSSIINNGG

An address represents the number of a line in the buffer. eedd maintains

a 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.

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 (i.e., +, - and ^) and whitespace.

Addresses are read from left to right, and their values are computed

relative to the current address. One exception to the rule that addresses represent line numbers is the address 0 (zero). This means "before the first line," and is legal wherever it makes sense.

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 n-tuple of addresses

is given where n > 2, then the corresponding range is determined by the

last two addresses in the n-tuple. If only one address is expected,

then the last address is used.

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.

The following address symbols are recognized.

. The current line (address) in the buffer.

$ The last line in the buffer.

n The nth, line in the buffer where n is a number in the range

[0,$].

- or ^ The previous line. This is equivalent to -1 and may be

repeated with cumulative effect.

-n or ^n

The nth previous line, where n is a non-negative number.

+ The next line. This is equivalent to +1 and may be repeated

with cumulative effect. +n or whitespacen

The nth next line, where n is a non-negative number. white-

space followed by a number n is interpreted as +n.

, or %% The first through last lines in the buffer. This is equivalent

to the address range 1,$.

; The current through last lines in the buffer. This is equiva-

lent to the address range .,$.

/re/ The next line containing the regular expression re. The search wraps to the beginning of the buffer and continues down to the current line, if necessary. // repeats the last search. ?re? The previous line containing the regular expression re. The search wraps to the end of the buffer and continues up to the current line, if necessary. ?? repeats the last search.

'lc The line previously marked by a `k' (mark) command, where lc is

a lower case letter. RREEGGUULLAARR EEXXPPRREESSSSIIOONNSS

Regular expressions are patterns used in selecting text. For example,

the eedd command

g/string/

prints all lines containing string. Regular expressions are also used

by the `s' command for selecting old text to be replaced with new.

In addition to a specifying string literals, regular expressions can

represent classes of strings. Strings thus represented are said to be

matched by the corresponding regular expression. If it is possible for

a regular expression to match several strings in a line, then the left-

most longest match is the one selected.

The following symbols are used in constructing regular expressions:

c Any character c not listed below, including `{', '}', `(', `)',

`<' and `>', matches itself.

\c Any backslash-escaped character c, except for `{', '}', `(',

`)', `<' and `>', matches itself. . Matches any single character.

[char-class]

Matches any single character in char-class. To include a `]'

in char-class, it must be the first character. A range of

characters may be specified by separating the end characters of

the range with a `-', e.g., `a-z' specifies the lower case

characters. The following literal expressions can also be used

in char-class to specify sets of characters:

[:alnum:] [:cntrl:] [:lower:] [:space:] [:alpha:] [:digit:] [:print:] [:upper:] [:blank:] [:graph:] [:punct:] [:xdigit:]

If `-' appears as the first or last character of char-class,

then it matches itself. All other characters in char-class

match themselves.

Patterns in char-class of the form:

[.col-elm.] or, [=col-elm=]

where col-elm is a collating element are interpreted according

to locale(5) (not currently supported). See regex(3) for an

explanation of these constructs.

[^char-class]

Matches any single character, other than newline, not in char-

class. char-class is defined as above.

^ If `^' is the first character of a regular expression, then it anchors the regular expression to the beginning of a line. Otherwise, it matches itself.

$ If `$' is the last character of a regular expression, it

anchors the regular expression to the end of a line. Other-

wise, it matches itself.

\< Anchors the single character regular expression or subexpres-

sion immediately following it to the beginning of a word.

(This may not be available)

\> Anchors the single character regular expression or subexpres-

sion immediately following it to the end of a word. (This may

not be available)

$re$ Defines a subexpression re. Subexpressions may be nested. A

subsequent backreference of the form `\n', where n is a number

in the range [1,9], expands to the text matched by the nth

subexpression. For example, the regular expression `$.*$\1' matches any string consisting of identical adjacent substrings.

Subexpressions are ordered relative to their left delimiter.

* Matches the single character regular expression or subexpres-

sion immediately preceding it zero or more times. If '*' is

the first character of a regular expression or subexpression, then it matches itself. The `*' operator sometimes yields

unexpected results. For example, the regular expression `b*'

matches the beginning of the string `abbb' (as opposed to the

substring `bbb'), since a null match is the only left-most

match. \{n,m\} or \{n,\} or \{n\}

Matches the single character regular expression or subexpres-

sion immediately preceding it at least n and at most m times.

If m is omitted, then it matches at least n times. If the

comma is also omitted, then it matches exactly n times.

Additional regular expression operators may be defined depending on the

particular regex(3) implementation. CCOOMMMMAANNDDSS

All eedd 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 (\).

In general, at most one command is allowed per line. However, most

commands accept a print suffix, which is any of `p' (print), `l' (list)

, or `n' (enumerate), to print the last line affected by the command.

An interrupt (typically ^C) has the effect of aborting the current com-

mand and returning the editor to command mode.

eedd recognizes the following commands. The commands are shown together

with the default address or address range supplied if none is specified

(in parenthesis).

(.)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.

(.,.)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.

(.,.)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.

e file Edits file, and sets the default filename. If file is not

specified, then the default filename is used. Any lines in

the buffer are deleted before the new file is read. The cur-

rent address is set to the last line read. e !command Edits the standard output of `!command', (see !command below).

The default filename is unchanged. Any lines in the buffer are

deleted before the output of command is read. The current

address is set to the last line read. E file Edits file unconditionally. This is similar to the e command,

except that unwritten changes are discarded without warning.

The current address is set to the last line read.

f file Sets the default filename to file. If file is not specified,

then the default unescaped filename is printed.

(1,$)g/re/command-list

Applies command-list to each of the addressed lines matching a

regular expression re. The current address is set to the line

currently matched before command-list is executed. At the end

of the `g' command, the current address is set to the last line

affected by command-list.

Each command in command-list must be on a separate line, and

every line except for the last must be terminated by a back-

slash (\). Any commands are allowed, except for `g', `G', `v',

and `V'. A newline alone in command-list is equivalent to a

`p' command.

(1,$)G/re/

Interactively edits the addressed lines matching a regular

expression re. For each matching line, the line is printed,

the current address is set, and the user is prompted to enter a

command-list. At the end of the `G' command, the current

address is set to the last line affected by (the last) command-

list.

The format of command-list is the same as that of the `g' com-

mand. A newline alone acts as a null command list. A single

`&' repeats the last non-null command list.

H Toggles the printing of error explanations. By default, expla-

nations are not printed. It is recommended that ed scripts

begin with this command to aid in debugging. h Prints an explanation of the last error. (.)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.

(.,.+1)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.

(.)klc Marks a line with a lower case letter lc. The line can then

be addressed as 'lc (i.e., a single quote followed by lc ) in

subsequent commands. The mark is not cleared until the line is

deleted or otherwise modified.

(.,.)l Prints the addressed lines unambiguously. If a single line

fills for than one screen (as might be the case when viewing a

binary file, for instance), a `-More-' prompt is printed on

the last line. eedd waits until the RETURN key is pressed before

displaying the next screen. The current address is set to the

last line printed.

(.,.)m(.)

Moves lines in the buffer. The addressed lines are moved to

after the right-hand destination address, which may be the

address 0 (zero). The current address is set to the last line

moved.

(.,.)n Prints the addressed lines along with their line numbers. The

current address is set to the last line printed.

(.,.)p Prints the addressed lines. The current address is set to the

last line printed.

P Toggles the command prompt on and off. Unless a prompt was

specified by with command-line option -p string, the command

prompt is by default turned off.

q Quits ed.

Q Quits ed unconditionally. This is similar to the q command,

except that unwritten changes are discarded without warning.

($)r file

Reads file to after the addressed line. If file is not speci-

fied, then the default filename is used. If there was no

default filename prior to the command, then the default file-

name is set to file. Otherwise, the default filename is

unchanged. The current address is set to the last line read.

($)r !command

Reads to after the addressed line the standard output of `!com-

mand', (see the !command below). The default filename is

unchanged. The current address is set to the last line read.

(.,.)s/re/replacement/ (.,.)s/re/replacement/g (.,.)s/re/replacement/n

Replaces text in the addressed lines matching a regular expres-

sion re with replacement. By default, only the first match in

each line is replaced. If the `g' (global) suffix is given,

then every match to be replaced. The `n' suffix, where n is a

positive number, causes only the nth 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.

re and replacement may be delimited by any character other than

space and newline (see the `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 `p' were specified.

An unescaped `&' in replacement is replaced by the currently

matched text. The character sequence `\m', where m is a number

in the range [1,9], is replaced by the mth backreference

expression of the matched text. If replacement consists of a

single `%', then replacement from the last substitution is

used. Newlines may be embedded in replacement if they are

escaped with a backslash (\).

(.,.)s Repeats the last substitution. This form of the `s' command

accepts a count suffix `n', or any combination of the charac-

ters `r', `g', and `p'. If a count suffix `n' is given, then

only the nth match is replaced. The `r' suffix causes the reg-

ular expression of the last search to be used instead of the

that of the last substitution. The `g' suffix toggles the global suffix of the last substitution. The `p' suffix toggles the print suffix of the last substitution The current address

is set to the last line affected.

(.,.)t(.)

Copies (i.e., transfers) the addressed lines to after the

right-hand destination address, which may be the address 0

(zero). The current address is set to the last line copied.

u Undoes the last command and restores the current address to what it was before the command. The global commands `g', `G',

`v', and `V'. are treated as a single command by undo. `u' is

its own inverse.

(1,$)v/pat/command-list

Applies command-list to each of the addressed lines not match-

ing a regular expression re. This is similar to the `g' com-

mand.

(1,$)V/re/

Interactively edits the addressed lines not matching a regular

expression re. This is similar to the `G' command.

(1,$)w file

Writes the addressed lines to file. Any previous contents of

file is lost without warning. If there is no default filename, then the default filename is set to file, otherwise it is

unchanged. If no filename is specified, then the default file-

name is used. The current address is unchanged.

(1,$)wq file

Writes the addressed lines to file, and then executes a `q'

command.

(1,$)w !command

Writes the addressed lines to the standard input of `!command',

(see the !command below). The default filename and current

address are unchanged.

(1,$)W file

Appends the addressed lines to the end of file. This is simi-

lar to the `w' command, expect that the previous contents of

file is not clobbered. The current address is unchanged.

x Prompts for an encryption key which is used in subsequent reads

and writes. If a newline alone is entered as the key, then

encryption is turned off. Otherwise, echoing is disabled while

a key is read. Encryption/decryption is done using the bdes(1) algorithm.

(.+1)zn Scrolls n lines at a time starting at addressed line. If n is

not specified, then the current window size is used. The cur-

rent address is set to the last line printed.

!command Executes command via sh(1). If the first character of command

is `!', then it is replaced by text of the previous `!command'.

eedd does not process command for backslash (\) escapes. How-

ever, an unescaped `%' is replaced by the default filename.

When the shell returns from execution, a `!' is printed to the

standard output. The current line is unchanged.

($)= Prints the line number of the addressed line.

(.+1)newline

Prints the addressed line, and sets the current address to that

line. FILES

/tmp/ed.* Buffer file

ed.hup The file to which eedd attempts to write the buffer

if the terminal hangs up.

vi(1), sed(1), regex(3), bdes(1), sh(1), compat(1).

USD:12-13

B. W. Kernighan and P. J. Plauger, Software Tools in Pascal , Addison-

Wesley, 1981. LLIIMMIITTAATTIIOONNSS

eedd processes file arguments for backslash escapes, i.e., in a file-

name, any characters preceded by a backslash (\) are interpreted liter-

ally.

If a text (non-binary) file is not terminated by a newline character,

then eedd appends one on reading/writing it. In the case of a binary

file, eedd does not append a newline on reading/writing.

per line overhead: 4 ints DIAGNOSTICS

When an error occurs, eedd prints a `?' 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 `h' (help) command.

Since the `g' (global) command masks any errors from failed searches

and substitutions, it can be used to perform conditional operations in

scripts; e.g., g/old/s//new/ replaces any occurrences of old with new. If the `u' (undo) command