sed(1)

NAME

sed − stream editor

SYNOPSIS

sed [−n] [−e script] [−f sfilename] [filename ...]

AVAILABILITY

SUNWcsu

DESCRIPTION

sed copies the named filename (standard input default) to the standard output, edited according to a script of commands.

OPTIONS

−n Suppress the default output.

−e script script is an edit command for sed. See USAGE below for more information on the format of script. If there is just one −e option and no −f options, the flag −e may be omitted.

−f sfilename Take the script from sfilename.

USAGE

A script consists of editing commands, one per line, of the following form:

[ address [ , address ] ] function [ arguments ]

In normal operation, sed cyclically copies a line of input into a pattern space (unless there is something left after a D command), applies in sequence all commands whose addresses select that pattern space, and copies the resulting pattern space to the standard output (except under −n).

Some of the commands use a hold space to save all or part of the pattern space for subsequent retrieval.

An address is either a decimal number that counts input lines cumulatively across files, a $ that addresses the last line of input, or a context address, that is, a /regular expression/ in the style of ed(1) modified thus:

• In a context address, the construction \?regular expression?, where ? is any character, is identical to /regular expression/. Note: In the context address \xabc\xdefx, the second x stands for itself, so that the regular expression is abcxdef.

• The escape sequence \n matches a new-line embedded in the pattern space.

• A period (.) matches any character except the terminal new-line of the pattern space.

• A command line with no addresses selects every line.

• A command line with one address selects each line that matches the address.

• A command line with two addresses selects the inclusive range from the first pattern space that matches the first address through the next pattern space that matches the second address. Thereafter the process is repeated, looking again for the first address. (If the second address is a number less than or equal to the line number selected by the first address, only the line corresponding to the first address is selected.)

Editing commands can be applied only to non-selected pattern spaces by use of the negation function ! (described below).

In the following list of functions the maximum number of permissible addresses for each function is indicated.

The text argument consists of one or more lines, all but the last of which end with \ to hide the new-line. Backslashes in text are treated like backslashes in the replacement string of an s command, and may be used to protect initial blanks and tabs against the stripping that is done on every script line. The rfile or wfile argument must terminate the command line and must be preceded by exactly one blank. Each wfile is created before processing begins. There can be at most 10 distinct wfile arguments.

The following table lists the functions.

Maximum	Com-	Description
Number of	mand
Addresses
1	a\
	text	Append. Place text on the output before reading the next input line.
2	b label	Branch to the : command bearing the label. If label is empty, branch
		to the end of the script.
2	c\
	text	Change. Delete the pattern space. Place text on the output. Start the
		next cycle.
2	d	Delete the pattern space. Start the next cycle.
2	D	Delete the initial segment of the pattern space through the first new-line.
		Start the next cycle. (See the N command below.)
2	g	Replace the contents of the pattern space by the contents of the hold space.
2	G	Append the contents of the hold space to the pattern space.
2	h	Replace the contents of the hold space by the contents of the pattern space.
2	H	Append the contents of the pattern space to the hold space.
1	i\
	text	Insert. Place text on the standard output.
2	l	List the pattern space on the standard output in an unambiguous form.
		Non-printable characters are displayed in octal notation and long lines
		are folded.
2	n	Copy the pattern space to the standard output. Replace the pattern space
		with the next line of input.
2	N	Append the next line of input to the pattern space with an embedded
		new-line. (The current line number changes.)
2	p	Print. Copy the pattern space to the standard output.
2	P	Copy the initial segment of the pattern space through the first
		new-line to the standard output.
1	q	Quit. Branch to the end of the script. Do not start a new cycle.
2	r rfile	Read the contents of rfile. Place them on the output before reading the
		next input line.

Maximum	Command	Description
Number of
Addresses
2	t label	Test. Branch to the : command bearing the label if any substitutions have
		been made since the most recent reading of an input line or execution of a
		t. If label is empty, branch to the end of the script.
2	w wfile	Write. Append the pattern space to wfile. The first occurrence of w will
		cause wfile to be cleared. Subsequent invocations of w will append. Each
		time the sed command is used, wfile is overwritten.
2	x	Exchange the contents of the pattern and hold spaces.
2	! function	Don’t. Apply the function (or group, if function is {) only to lines not
		selected by the address(es).
0	: label\f1	This command does nothing; it bears a label for b and t commands
		to branch to.
1	=	Place the current line number on the standard output as a line.
2	{	Execute the following commands through a matching } only when the
		pattern space is selected.
0		An empty command is ignored.
0	#	If a # appears as the first character on a line of a script file, then that entire
		line is treated as a comment, with one exception: if a # appears on the first
		line and the character after the # is an n, then the default output will be
		suppressed. The rest of the line after #n is also ignored. A script file must
		contain at least one non-comment line.

Maximum	Command (Using strings) and Description
Number of
Addresses
2	s/regular expression/replacement/flags
	Substitute the replacement string for instances of the regular expression in the pattern
	space. Any character may be used instead of /. For a fuller description see ed (1).
	flags is zero or more of:

	n n= 1 - 512. Substitute for just the n th occurrence of the regular expression.

	g Global. Substitute for all nonoverlapping instances of the regular expression rather
	than just the first one.

	p Print the pattern space if a replacement was made.

	w wfile Write. Append the pattern space to wfile if a replacement was made.
2	y/ string1 / string2 /
	Transform. Replace all occurrences of characters in string1 with the corresponding
	characters in string2. string1 and string2 must have the same number of characters.
	For example, y/abc/ABC/ replaces a with A, b with B, and c with C.

ENVIRONMENT

If any of the LC_∗ variables ( LC_CTYPE, LC_MESSAGES, LC_TIME, LC_COLLATE, LC_NUMERIC, and LC_MONETARY ) (see environ(5)) are not set in the environment, the operational behavior of sed for each corresponding locale category is determined by the value of the LANG environment variable. If LC_ALL is set, its contents are used to override both the LANG and the other LC_∗ variables. If none of the above variables is set in the environment, the "C" (U.S. style) locale determines how sed behaves.

LC_CTYPE
Determines how sed handles characters. When LC_CTYPE is set to a valid value, sed can display and handle text and filenames containing valid characters for that locale. sed can display and handle Extended Unix Code (EUC) characters where any individual character can be 1, 2, or 3 bytes wide. sed can also handle EUC characters of 1, 2, or more column widths. In the "C" locale, only characters from ISO 8859-1 are valid.

LC_MESSAGES
Determines how diagnostic and informative messages are presented. This includes the language and style of the messages, and the correct form of affirmative and negative responses. In the "C" locale, the messages are presented in the default form found in the program itself (in most cases, U.S. English).

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