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SED(1)				 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 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

       -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; hard links will still
	      be broken.

       -i[SUFFIX], --in-place[=SUFFIX]

	      edit files in place (makes backup if extension  supplied).   The
	      default  operation  mode	is  to	break symbolic and hard links.
	      This can be changed with --follow-symlinks and --copy.

       -c, --copy

	      use copy instead of rename when  shuffling  files	 in  -i	 mode.
	      While  this  will	 avoid	breaking links (symbolic or hard), the
	      resulting editing operation is not atomic.  This is  rarely  the
	      desired  mode;  --follow-symlinks	 is  usually enough, and it is
	      both faster and more secure.

       -l N, --line-length=N

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

       --posix

	      disable all GNU extensions.

       -r, --regexp-extended

	      use extended regular expressions in the script.

       -s, --separate

	      consider files as separate rather than as	 a  single  continuous
	      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/>.  General 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'' some-
       where 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 \

       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
	      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 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.

       t label
	      If a s/// has done a  successful	substitution  since  the  last
	      input  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
	      input  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.

       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      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  success-
	      ful,   replace  that  portion  matched  with  replacement.   The
	      replacement may contain the special character & 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; 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  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.

       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
	      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
	      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.

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 possi-
       ble.

COPYRIGHT
       Copyright (C) 2009 Free Software Foundation, Inc.
       This is free software; see the source for copying conditions.  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/>.  General 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'' some-
       where in the ``Subject:'' field.

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.



sed version 4.2.1		  March 2012				SED(1)