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SED(1)				 User Commands				SED(1)

NAME
       sed - stream editor for filtering and transforming text

SYNOPSIS
       sed [-V]	[--version] [--help] [-n] [--quiet] [--silent]
	   [-l N] [--line-length=N] [-u] [--unbuffered]
	   [-E]	[-r] [--regexp-extended]
	   [-e script] [--expression=script]
	   [-f script-file] [--file=script-file]
	   [script-if-no-other-script]
	   [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 consequently 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

       --debug

	      annotate program execution

       -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 SUFFIX supplied)

       -l N, --line-length=N

	      specify the desired line-wrap length for the `l' command

       --posix

	      disable all GNU extensions.

       -E, -r, --regexp-extended

	      use extended regular expressions in the script (for  portability
	      use POSIX	-E).

       -s, --separate

	      consider	files  as separate rather than as a single, continuous
	      long stream.

       --sandbox

	      operate in sandbox mode (disable e/r/w commands).

       -u, --unbuffered

	      load minimal amounts of data from	the input files	and flush  the
	      output buffers more often

       -z, --null-data

	      separate lines by	NUL characters

       --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  re-
       maining arguments are names of input files; if no input files are spec-
       ified, then the standard	input is read.

       GNU  sed	 home page: <https://www.gnu.org/software/sed/>.  General help
       using GNU software: <https://www.gnu.org/gethelp/>.  E-mail bug reports
       to: <bug-sed@gnu.org>.

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 \

       text   Append text, which has each embedded newline preceded by a back-
	      slash.

       i \

       text   Insert text, which has each embedded newline preceded by a back-
	      slash.

       q [exit-code]
	      Immediately quit the sed script without processing any more  in-
	      put,  except that	if auto-print is not disabled the current pat-
	      tern space will be printed.  The exit code argument is a GNU ex-
	      tension.

       Q [exit-code]
	      Immediately quit the sed script without processing any more  in-
	      put.  This is a GNU extension.

       r filename
	      Append text read from filename.

       R filename
	      Append  a	 line read from	filename.  Each	invocation of the com-
	      mand 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.

       c \

       text   Replace the selected lines with text, which  has	each  embedded
	      newline preceded by a backslash.

       d      Delete pattern space.  Start next	cycle.

       D      If  pattern  space contains no newline, start a normal new cycle
	      as if the	d command was issued.  Otherwise, delete text  in  the
	      pattern  space  up  to the first newline,	and restart cycle with
	      the resultant pattern space, without reading a new line  of  in-
	      put.

       h H    Copy/append pattern space	to hold	space.

       g G    Copy/append hold space to	pattern	space.

       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 success-
	      ful, replace that	portion	matched	 with  replacement.   The  re-
	      placement	 may  contain the special character & to refer to that
	      portion of the pattern space which matched, and the special  es-
	      capes  \1	through	\9 to refer to the corresponding matching sub-
	      expressions in the regexp.

       t label
	      If a s///	has done a successful substitution since the last  in-
	      put line was read	and since the last t or	T command, 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 in-
	      put line was read	and since the last t or	T command, then	branch
	      to label;	if label is omitted, branch to end of script.  This is
	      a	GNU extension.

       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.

       x      Exchange the contents of the hold	and pattern spaces.

       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; with one address, in  which  case
       the  command will only be executed for input lines which	match that ad-
       dress; or with two addresses, in	which case the command	will  be  exe-
       cuted  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 command, 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 (which increments cumula-
	      tively across files, unless the -s option	is  specified  on  the
	      command line).

       first~step
	      Match every step'th line starting	with line first.  For example,
	      ``sed -n 1~2p'' will print all the odd-numbered lines in the in-
	      put  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.  Matching is
	      performed	 on  the  current pattern space, which can be modified
	      with commands such as ``s///''.

       \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  be-
	      ginning  of  its range.  This works only when addr2 is a regular
	      expression.

       addr1,+N
	      Will match addr1 and the N lines following addr1.

       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 regular expression matches
       the newline character, and similarly for	\a, \t,	and  other  sequences.
       The  -E	option switches	to using extended regular expressions instead;
       it has been supported for years by GNU sed,  and	 is  now  included  in
       POSIX.

BUGS
       E-mail bug reports to bug-sed@gnu.org.  Also, please include the	output
       of ``sed	--version'' in the body	of your	report if at all possible.

AUTHOR
       Written by Jay Fenlason,	Tom Lord, Ken Pizzini, Paolo Bonzini, Jim Mey-
       ering, and Assaf	Gordon.

       This sed	program	was built without SELinux support.

       GNU  sed	 home page: <https://www.gnu.org/software/sed/>.  General help
       using GNU software: <https://www.gnu.org/gethelp/>.  E-mail bug reports
       to: <bug-sed@gnu.org>.

COPYRIGHT
       Copyright (C) 2022 Free Software	Foundation, Inc.  License GPLv3+:  GNU
       GPL version 3 or	later <https://gnu.org/licenses/gpl.html>.
       This  is	 free  software:  you  are free	to change and redistribute it.
       There is	NO WARRANTY, to	the extent permitted by	law.

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/grabbag/tutorials/sed-
       faq.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 com-
       mand

	      info sed

       should give you access to the complete manual.

GNU sed	4.9			  April	2025				SED(1)

Want to link to this manual page? Use this URL:
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