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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

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

              edit files in place (makes backup if SUFFIX supplied)

       -c, --copy

              use copy instead of rename when shuffling files in -i mode

       -b, --binary

              does nothing; for compatibility with WIN32/CYGWIN/MSDOS/EMX ( open files in binary mode (CR+LFs are not
              treated specially))

       -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.

       --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: <[email protected]>.  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 doc‐
       umentation (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 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 }).


       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 successful, replace that portion matched with
              replacement.  The replacement may contain the special character & to refer to that portion of the  pat‐
              tern  space which matched, and the special escapes \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 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 exten‐
              sion.

       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 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 command, a !  may be inserted, which specifies  that  the

       $      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  multi‐
              ple 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 [email protected].  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,   and   Paolo   Bonzini.   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: <[email protected]>.  Be sure to include the word ``sed'' somewhere in the ``Subject:'' field.

COPYRIGHT
       Copyright   ©   2012   Free   Software   Foundation,  Inc.   License  GPLv3+:  GNU  GPL  version  3  or  later
       <http://gnu.org/licenses/gpl.html>.
       This is free software: you are free to change and redistribute it.  There is NO WARRANTY, to the  extent  per‐
       mitted 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/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

       should give you access to the complete manual.