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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 in‐
       put(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 remaining arguments are names of input files; if
       no input files are specified, 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 AT 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 de‐
       scriptions.

   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 ex‐
              tension.

       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 }).

       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 input.

       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 por‐
              tion 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.

       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.

       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  exten‐
              sion.

       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 corre‐
              sponding 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 (which increments cumulatively across files, un‐
              less 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 input stream, and the address 2~5 will match
              every fifth line, starting with the second.  first can be zero; in this case, sed  op‐
              erates 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 cur‐
              rent 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  begin‐
              ning 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  in‐
       stead; it has been supported for years by GNU sed, and is now included in POSIX.

BUGS
       E-mail  bug reports to bug-sed AT 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 Meyering, and  Assaf  Gor‐
       don.

       This sed program was built with SELinux support.  SELinux is enabled on this system.

       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 AT gnu.org>.

COPYRIGHT
       Copyright © 2020 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/sedfaq.txt), http://sed.sf.net/grabbag/.

       The full documentation for sed is maintained as a Texinfo manual.  If the info and sed pro‐
       grams are properly installed at your site, the command

              info sed

       should give you access to the complete manual.



sed 4.8                                     January 2020                                      SED(1)