sed


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)

       -c, --copy

              use  copy  instead  of  rename  when  shuffling files in -i mode
              (avoids change of input file ownership)

       -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

       ''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

       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
       /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 (C) 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.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.
Subscribe to us on YouTube