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SED(1)                           User Commands                          SED(1)



NAME
       sed - manual page for sed version 4.1.2

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

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

              edit files in place (makes backup if extension supplied)

       -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.

       E-mail bug reports to: bonzini@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 \

       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      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.

       Q      Immediately quit the sed  script  without  processing  any  more
              input.

       r filename
              Append text read from filename.

       R filename
              Append a line read from filename.

   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.

       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.

       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.

       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. (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.

       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 .© 2003 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.

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.html), 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 4.1.2                 August 2004                           SED(1)



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