sed
(1g)
Name
sed - stream editor for filtering and transforming text
Synopsis
sed [OPTION]... {script-only-if-no-other-script} [input-
file]...
Description
User Commands SED(1)
NAME
sed - stream editor for filtering and transforming text
SYNOPSIS
sed [OPTION]... {script-only-if-no-other-script} [input-
file]...
DESCRIPTION
Sed is a stream editor. A stream editor is used to perform
basic text transformations on an input stream (a file or
input from a pipeline). While in some ways similar to an
editor which permits scripted edits (such as ed), sed works
by making only one pass over the input(s), and is conse-
quently more efficient. But it is sed's ability to filter
text in a pipeline which particularly distinguishes it from
other types of editors.
-n, --quiet, --silent
suppress automatic printing of pattern space
-e script, --expression=script
add the script to the commands to be executed
-f script-file, --file=script-file
add the contents of script-file to the commands to be
executed
--follow-symlinks
follow symlinks when processing in place
-i[SUFFIX], --in-place[=SUFFIX]
edit files in place (makes backup if extension sup-
plied)
-l N, --line-length=N
specify the desired line-wrap length for the `l' com-
mand
--posix
disable all GNU extensions.
-r, --regexp-extended
use extended regular expressions in the script.
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-s, --separate
consider files as separate rather than as a single con-
tinuous long stream.
-u, --unbuffered
load minimal amounts of data from the input files and
flush the output buffers more often
--help
display this help and exit
--version
output version information and exit
If no -e, --expression, -f, or --file option is given, then
the first non-option argument is taken as the sed script to
interpret. All remaining arguments are names of input
files; if no input files are specified, then the standard
input is read.
GNU sed home page: <http://www.gnu.org/software/sed/>. Gen-
eral help using GNU software: <http://www.gnu.org/gethelp/>.
E-mail bug reports to: <bug-gnu-utils@gnu.org>. Be sure to
include the word ``sed'' somewhere in the ``Subject:''
field.
COMMAND SYNOPSIS
This is just a brief synopsis of sed commands to serve as a
reminder to those who already know sed; other documentation
(such as the texinfo document) must be consulted for fuller
descriptions.
Zero-address ``commands''
: label
Label for b and t commands.
#comment
The comment extends until the next newline (or the end
of a -e script fragment).
} The closing bracket of a { } block.
Zero- or One- address commands
= Print the current line number.
a \
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text Append text, which has each embedded newline preceded
by a backslash.
i \
text Insert text, which has each embedded newline preceded
by a backslash.
q [exit-code]
Immediately quit the sed script without processing any
more input, except that if auto-print is not disabled
the current pattern space will be printed. The exit
code argument is a GNU extension.
Q [exit-code]
Immediately quit the sed script without processing any
more input. This is a GNU extension.
r filename
Append text read from filename.
R filename
Append a line read from filename. Each invocation of
the command reads a line from the file. This is a GNU
extension.
Commands which accept address ranges
{ Begin a block of commands (end with a }).
b label
Branch to label; if label is omitted, branch to end of
script.
t label
If a s/// has done a successful substitution since the
last input line was read and since the last t or T com-
mand, then branch to label; if label is omitted, branch
to end of script.
T label
If no s/// has done a successful substitution since the
last input line was read and since the last t or T com-
mand, then branch to label; if label is omitted, branch
to end of script. This is a GNU extension.
c \
text Replace the selected lines with text, which has each
embedded newline preceded by a backslash.
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d Delete pattern space. Start next cycle.
D Delete up to the first embedded newline in the pattern
space. Start next cycle, but skip reading from the
input if there is still data in the pattern space.
h H Copy/append pattern space to hold space.
g G Copy/append hold space to pattern space.
x Exchange the contents of the hold and pattern spaces.
l List out the current line in a ``visually unambiguous''
form.
l width
List out the current line in a ``visually unambiguous''
form, breaking it at width characters. This is a GNU
extension.
n N Read/append the next line of input into the pattern
space.
p Print the current pattern space.
P Print up to the first embedded newline of the current
pattern space.
s/regexp/replacement/
Attempt to match regexp against the pattern space. If
successful, replace that portion matched with replace-
ment. The replacement may contain the special charac-
ter & to refer to that portion of the pattern space
which matched, and the special escapes \1 through \9 to
refer to the corresponding matching sub-expressions in
the regexp.
w filename
Write the current pattern space to filename.
W filename
Write the first line of the current pattern space to
filename. This is a GNU extension.
y/source/dest/
Transliterate the characters in the pattern space which
appear in source to the corresponding character in
dest.
Addresses Sed commands can be given with no addresses, in
which case the command will be executed for all input lines;
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with one address, in which case the command will only be
executed for input lines which match that address; or with
two addresses, in which case the command will be executed
for all input lines which match the inclusive range of lines
starting from the first address and continuing to the second
address. Three things to note about address ranges: the
syntax is addr1,addr2 (i.e., the addresses are separated by
a comma); the line which addr1 matched will always be
accepted, even if addr2 selects an earlier line; and if
addr2 is a regexp, it will not be tested against the line
that addr1 matched.
After the address (or address-range), and before the com-
mand, a ! may be inserted, which specifies that the command
shall only be executed if the address (or address-range)
does not match.
The following address types are supported:
number
Match only the specified line number.
first~step
Match every step'th line starting with line first. For
example, ``sed -n 1~2p'' will print all the odd-num-
bered lines in the input stream, and the address 2~5
will match every fifth line, starting with the second.
first can be zero; in this case, sed operates as if it
were equal to step. (This is an extension.)
$ Match the last line.
/regexp/
Match lines matching the regular expression regexp.
\cregexpc
Match lines matching the regular expression regexp.
The c may be any character.
GNU sed also supports some special 2-address forms:
0,addr2
Start out in "matched first address" state, until addr2
is found. This is similar to 1,addr2, except that if
addr2 matches the very first line of input the 0,addr2
form will be at the end of its range, whereas the
1,addr2 form will still be at the beginning of its
range. This works only when addr2 is a regular expres-
sion.
addr1,+N
Will match addr1 and the N lines following addr1.
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addr1,~N
Will match addr1 and the lines following addr1 until
the next line whose input line number is a multiple of
N.
REGULAR EXPRESSIONS
POSIX.2 BREs should be supported, but they aren't completely
because of performance problems. The \n sequence in a regu-
lar expression matches the newline character, and similarly
for \a, \t, and other sequences.
BUGS
E-mail bug reports to bonzini@gnu.org. Be sure to include
the word ``sed'' somewhere in the ``Subject:'' field. Also,
please include the output of ``sed --version'' in the body
of your report if at all possible.
COPYRIGHT
Copyright (C) 2009 Free Software Foundation, Inc.
This is free software; see the source for copying condi-
tions. There is NO warranty; not even for MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE, to the extent permitted
by law.
GNU sed home page: <http://www.gnu.org/software/sed/>. Gen-
eral help using GNU software: <http://www.gnu.org/gethelp/>.
E-mail bug reports to: <bug-gnu-utils@gnu.org>. Be sure to
include the word ``sed'' somewhere in the ``Subject:''
field.
ATTRIBUTES
See attributes(5) for descriptions of the following
attributes:
+---------------+------------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+------------------+
|Availability | text/gnu-sed |
+---------------+------------------+
|Stability | Volatile |
+---------------+------------------+
SEE ALSO
awk(1), ed(1), grep(1), tr(1), perlre(1), sed.info, any of
various books on sed, the sed FAQ (http://sed.sf.net/grab-
bag/tutorials/sedfaq.txt), http://sed.sf.net/grabbag/.
The full documentation for sed is maintained as a Texinfo
manual. If the info and sed programs are properly installed
at your site, the command
info sed
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should give you access to the complete manual.
NOTES
This software was built from source available at
https://java.net/projects/solaris-userland. The original
community source was downloaded from
http://ftp.gnu.org/pub/gnu/sed/sed-4.2.1.tar.gz
Further information about this software can be found on the
open source community website at http://www.gnu.org/soft-
ware/sed/.
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