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 pipe-
       line).  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 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.

       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: <bug-gnu-utils@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  tex-
       info 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 }).

       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      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.

       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 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 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 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.  first can be zero; in this case, sed operates as
	      if it were equal to step.  (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.  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 
 sequence in a regular expression
       matches the newline character, and similarly for a, 	, 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 possible.

COPYRIGHT

       Copyright (C) 2009 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 PARTICU-
       LAR PURPOSE, to the extent permitted by law.

       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: <bug-gnu-utils@gnu.org>.  Be sure to include the word ``sed'' somewhere in the ``Subject:'' field.

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
       command

	      info sed

       should give you access to the complete manual.

sed 4.2.1							   December 2010							    SED(1)