SED(1) SED(1)
NAME
sed - stream editor
SYNOPSIS
sed [ -n ] [ -e script ] [ -f sfile ] [ file ] ...
DESCRIPTION
Sed copies the named files (standard input default) to the
standard output, edited according to a script of commands.
The -f option causes the script to be taken from file
sfile; these options accumulate. If there is just one -e
option and no -f's, the flag -e may be omitted. The -n
option suppresses the default output.
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 at the end of the
script copies the pattern space to the standard output
(except under -n) and deletes the pattern space.
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, `/regular
expression/', in the style of ed(1) modified thus:
The escape sequence `\n' matches a newline embedded
in the pattern space.
A command line with no addresses selects every pattern
space.
A command line with one address selects each pattern space
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. (If the second address is a number less than or
equal to the line number first selected, only one line is
selected.) Thereafter the process is repeated, looking
again for the first address.
Editing commands can be applied only to non-selected pat-
tern spaces by use of the negation function `!' (below).
In the following list of functions the maximum number of
permissible addresses for each function is indicated in
parentheses.
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SED(1) SED(1)
An argument denoted text 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.
An argument denoted rfile or wfile must terminate the com-
mand 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.
(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. With 0 or 1
address or at the end of a 2-address range, 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 newline. Start the next cycle.
(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 pat-
tern space.
(2)h Replace the contents of the hold space by the con-
tents 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-printing characters are
spelled in two digit ascii, and long lines are
folded.
(2)n Copy the pattern space to the standard output.
Replace the pattern space with the next line of
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SED(1) SED(1)
input.
(2)N Append the next line of input to the pattern space
with an embedded newline. (The current line number
changes.)
(2)p Print. Copy the pattern space to the standard out-
put.
(2)P Copy the initial segment of the pattern space
through the first newline 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 out-
put before reading the next input line.
(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
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)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.
(2)x Exchange the contents of the pattern and hold
spaces.
(2)y/string1/string2/
Transform. Replace all occurrences of characters
in string1 with the corresponding character in
string2. The lengths of string1 and string2 must
be equal.
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SED(1) SED(1)
(2)! function
Don't. Apply the function (or group, if function
is `{') only to lines not selected by the
address(es).
(0): label
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 out-
put as a line.
(2){ Execute the following commands through a matching
`}' only when the pattern space is selected.
(0) An empty command is ignored.
SEE ALSO
ed(1), grep(1), awk(1)
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