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SED(1)                      General Commands Manual                     SED(1)



NAME
       sed - stream editor

SYNOPSIS
       sed [ -n ] [ -e script ] [ -f sfile ] [ file ] ...

DESCRIPTION
       Sed  copies  the  named  files (standard input default) to the standard
       output, edited according to a script of commands.  The -f option causes
       the  script  to be taken from file sfile; these options accumulate.  If
       there is just one -e option and no -f's, the flag -e  may  be  omitted.
       The -n option suppresses the default output.

       A  script  consists of editing commands, one per line, of the following
       form:

              [address [, address] ] function [arguments]

       In normal operation sed cyclically copies a line of input into  a  pat-
       tern  space  (unless  there  is  something  left  after a `D' command),
       applies in sequence all commands whose addresses  select  that  pattern
       space,  and  at  the  end of the script copies the pattern space to the
       standard output (except under -n) and deletes the pattern space.

       An address is either a decimal number that counts input  lines  cumula-
       tively  across files, a `$' that addresses the last line of input, or a
       context address, `/regular expression/', in the style of ed(1) modified
       thus:

              The  escape sequence `\n' matches a newline embedded in the pat-
              tern space.

       A command line with no addresses selects every pattern space.

       A command line with one address selects each pattern space that matches
       the address.

       A  command line with two addresses selects the inclusive range from the
       first pattern space that matches the first  address  through  the  next
       pattern  space  that  matches  the second.  (If the second address is a
       number less than or equal to the line number first selected,  only  one
       line  is  selected.)  Thereafter the process is repeated, looking again
       for the first address.

       Editing commands can be applied only to non-selected pattern spaces  by
       use of the negation function `!' (below).

       In  the  following  list of functions the maximum number of permissible
       addresses for each function is indicated in parentheses.

       An argument denoted text consists of one or more  lines,  all  but  the
       last  of  which  end with `\' to hide the newline.  Backslashes in text
       are treated like backslashes in the replacement string of an  `s'  com-
       mand,  and  may  be used to protect initial blanks and tabs against the
       stripping that is done on every script line.

       An argument denoted rfile or wfile must terminate the command line  and
       must  be  preceded  by exactly one blank.  Each wfile is created before
       processing begins.  There can be at most 10 distinct wfile arguments.

       (1)a\
       text
              Append.  Place text on the output before reading the next  input
              line.

       (2)b label
              Branch to the `:' command bearing the label.  If label is empty,
              branch to the end of the script.

       (2)c\
       text
              Change.  Delete the pattern space.  With 0 or 1  address  or  at
              the  end  of a 2-address range, place text on the output.  Start
              the next cycle.

       (2)d   Delete the pattern space.  Start the next cycle.

       (2)D   Delete the initial segment of  the  pattern  space  through  the
              first newline.  Start the next cycle.

       (2)g   Replace the contents of the pattern space by the contents of the
              hold space.

       (2)G   Append the contents of the hold space to the pattern space.

       (2)h   Replace the contents of the hold space by the  contents  of  the
              pattern space.

       (2)H   Append the contents of the pattern space to the hold space.

       (1)i\
       text   Insert.  Place text on the standard output.

       (2)l   List  the pattern space on the standard output in an unambiguous
              form.  Non-printing characters are spelled in two  digit  ascii,
              and long lines are folded.

       (2)n   Copy the pattern space to the standard output.  Replace the pat-
              tern space with the next line of input.

       (2)N   Append the next line of input  to  the  pattern  space  with  an
              embedded newline.  (The current line number changes.)

       (2)p   Print.  Copy the pattern space to the standard output.

       (2)P   Copy  the initial segment of the pattern space through the first
              newline to the standard output.

       (1)q   Quit.  Branch to the end of the script.   Do  not  start  a  new
              cycle.

       (2)r rfile
              Read  the  contents  of  rfile.  Place them on the output before
              reading the next input line.

       (2)s/regular expression/replacement/flags
              Substitute the replacement string for instances of  the  regular
              expression  in  the  pattern  space.   Any character may be used
              instead of `/'.  For a fuller description see ed(1).   Flags  is
              zero or more of

              g      Global.   Substitute  for all nonoverlapping instances of
                     the regular expression rather than just the first one.

              p      Print the pattern space if a replacement was made.

              w wfile
                     Write.  Append the pattern space to wfile if  a  replace-
                     ment was made.

       (2)t label
              Test.   Branch  to the `:' command bearing the label if any sub-
              stitutions have been made since the most recent  reading  of  an
              input  line or execution of a `t'.  If label is empty, branch to
              the end of the script.

       (2)w wfile
              Write.  Append the pattern space to wfile.

       (2)x   Exchange the contents of the pattern and hold spaces.

       (2)y/string1/string2/
              Transform.  Replace all occurrences  of  characters  in  string1
              with  the  corresponding  character  in string2.  The lengths of
              string1 and string2 must be equal.

       (2)! function
              Don't.  Apply the function (or group, if function is  `{')  only
              to lines not selected by the address(es).

       (0): label
              This command does nothing; it bears a label for `b' and `t' com-
              mands to branch to.

       (1)=   Place the current line number on the standard output as a line.

       (2){   Execute the following commands through a matching `}' only  when
              the pattern space is selected.

       (0)    An empty command is ignored.

SEE ALSO
       ed(1), grep(1), awk(1)



                                                                        SED(1)