svn commit: trunk/busybox/editors

vda at busybox.net vda at busybox.net
Tue Nov 13 17:13:33 UTC 2007


Author: vda
Date: 2007-11-13 09:13:31 -0800 (Tue, 13 Nov 2007)
New Revision: 20415

Log:
add sed mini-doc



Added:
   trunk/busybox/editors/sed1line.txt
   trunk/busybox/editors/sed_summary.htm


Changeset:
Added: trunk/busybox/editors/sed1line.txt
===================================================================
--- trunk/busybox/editors/sed1line.txt	                        (rev 0)
+++ trunk/busybox/editors/sed1line.txt	2007-11-13 17:13:31 UTC (rev 20415)
@@ -0,0 +1,425 @@
+http://www.student.northpark.edu/pemente/sed/sed1line.txt
+-------------------------------------------------------------------------
+HANDY ONE-LINERS FOR SED (Unix stream editor)               Apr. 26, 2004
+compiled by Eric Pement - pemente[at]northpark[dot]edu        version 5.4
+Latest version of this file is usually at:
+   http://sed.sourceforge.net/sed1line.txt
+   http://www.student.northpark.edu/pemente/sed/sed1line.txt
+This file is also available in Portuguese at:
+   http://www.lrv.ufsc.br/wmaker/sed_ptBR.html
+
+FILE SPACING:
+
+ # double space a file
+ sed G
+
+ # double space a file which already has blank lines in it. Output file
+ # should contain no more than one blank line between lines of text.
+ sed '/^$/d;G'
+
+ # triple space a file
+ sed 'G;G'
+
+ # undo double-spacing (assumes even-numbered lines are always blank)
+ sed 'n;d'
+
+ # insert a blank line above every line which matches "regex"
+ sed '/regex/{x;p;x;}'
+
+ # insert a blank line below every line which matches "regex"
+ sed '/regex/G'
+
+ # insert a blank line above and below every line which matches "regex"
+ sed '/regex/{x;p;x;G;}'
+
+NUMBERING:
+
+ # number each line of a file (simple left alignment). Using a tab (see
+ # note on '\t' at end of file) instead of space will preserve margins.
+ sed = filename | sed 'N;s/\n/\t/'
+
+ # number each line of a file (number on left, right-aligned)
+ sed = filename | sed 'N; s/^/     /; s/ *\(.\{6,\}\)\n/\1  /'
+
+ # number each line of file, but only print numbers if line is not blank
+ sed '/./=' filename | sed '/./N; s/\n/ /'
+
+ # count lines (emulates "wc -l")
+ sed -n '$='
+
+TEXT CONVERSION AND SUBSTITUTION:
+
+ # IN UNIX ENVIRONMENT: convert DOS newlines (CR/LF) to Unix format
+ sed 's/.$//'               # assumes that all lines end with CR/LF
+ sed 's/^M$//'              # in bash/tcsh, press Ctrl-V then Ctrl-M
+ sed 's/\x0D$//'            # gsed 3.02.80, but top script is easier
+
+ # IN UNIX ENVIRONMENT: convert Unix newlines (LF) to DOS format
+ sed "s/$/`echo -e \\\r`/"            # command line under ksh
+ sed 's/$'"/`echo \\\r`/"             # command line under bash
+ sed "s/$/`echo \\\r`/"               # command line under zsh
+ sed 's/$/\r/'                        # gsed 3.02.80
+
+ # IN DOS ENVIRONMENT: convert Unix newlines (LF) to DOS format
+ sed "s/$//"                          # method 1
+ sed -n p                             # method 2
+
+ # IN DOS ENVIRONMENT: convert DOS newlines (CR/LF) to Unix format
+ # Can only be done with UnxUtils sed, version 4.0.7 or higher.
+ # Cannot be done with other DOS versions of sed. Use "tr" instead.
+ sed "s/\r//" infile >outfile         # UnxUtils sed v4.0.7 or higher
+ tr -d \r <infile >outfile            # GNU tr version 1.22 or higher
+
+ # delete leading whitespace (spaces, tabs) from front of each line
+ # aligns all text flush left
+ sed 's/^[ \t]*//'                    # see note on '\t' at end of file
+
+ # delete trailing whitespace (spaces, tabs) from end of each line
+ sed 's/[ \t]*$//'                    # see note on '\t' at end of file
+
+ # delete BOTH leading and trailing whitespace from each line
+ sed 's/^[ \t]*//;s/[ \t]*$//'
+
+ # insert 5 blank spaces at beginning of each line (make page offset)
+ sed 's/^/     /'
+
+ # align all text flush right on a 79-column width
+ sed -e :a -e 's/^.\{1,78\}$/ &/;ta'  # set at 78 plus 1 space
+
+ # center all text in the middle of 79-column width. In method 1,
+ # spaces at the beginning of the line are significant, and trailing
+ # spaces are appended at the end of the line. In method 2, spaces at
+ # the beginning of the line are discarded in centering the line, and
+ # no trailing spaces appear at the end of lines.
+ sed  -e :a -e 's/^.\{1,77\}$/ & /;ta'                     # method 1
+ sed  -e :a -e 's/^.\{1,77\}$/ &/;ta' -e 's/\( *\)\1/\1/'  # method 2
+
+ # substitute (find and replace) "foo" with "bar" on each line
+ sed 's/foo/bar/'             # replaces only 1st instance in a line
+ sed 's/foo/bar/4'            # replaces only 4th instance in a line
+ sed 's/foo/bar/g'            # replaces ALL instances in a line
+ sed 's/\(.*\)foo\(.*foo\)/\1bar\2/' # replace the next-to-last case
+ sed 's/\(.*\)foo/\1bar/'            # replace only the last case
+
+ # substitute "foo" with "bar" ONLY for lines which contain "baz"
+ sed '/baz/s/foo/bar/g'
+
+ # substitute "foo" with "bar" EXCEPT for lines which contain "baz"
+ sed '/baz/!s/foo/bar/g'
+
+ # change "scarlet" or "ruby" or "puce" to "red"
+ sed 's/scarlet/red/g;s/ruby/red/g;s/puce/red/g'   # most seds
+ gsed 's/scarlet\|ruby\|puce/red/g'                # GNU sed only
+
+ # reverse order of lines (emulates "tac")
+ # bug/feature in HHsed v1.5 causes blank lines to be deleted
+ sed '1!G;h;$!d'               # method 1
+ sed -n '1!G;h;$p'             # method 2
+
+ # reverse each character on the line (emulates "rev")
+ sed '/\n/!G;s/\(.\)\(.*\n\)/&\2\1/;//D;s/.//'
+
+ # join pairs of lines side-by-side (like "paste")
+ sed '$!N;s/\n/ /'
+
+ # if a line ends with a backslash, append the next line to it
+ sed -e :a -e '/\\$/N; s/\\\n//; ta'
+
+ # if a line begins with an equal sign, append it to the previous line
+ # and replace the "=" with a single space
+ sed -e :a -e '$!N;s/\n=/ /;ta' -e 'P;D'
+
+ # add commas to numeric strings, changing "1234567" to "1,234,567"
+ gsed ':a;s/\B[0-9]\{3\}\>/,&/;ta'                     # GNU sed
+ sed -e :a -e 's/\(.*[0-9]\)\([0-9]\{3\}\)/\1,\2/;ta'  # other seds
+
+ # add commas to numbers with decimal points and minus signs (GNU sed)
+ gsed ':a;s/\(^\|[^0-9.]\)\([0-9]\+\)\([0-9]\{3\}\)/\1\2,\3/g;ta'
+
+ # add a blank line every 5 lines (after lines 5, 10, 15, 20, etc.)
+ gsed '0~5G'                  # GNU sed only
+ sed 'n;n;n;n;G;'             # other seds
+
+SELECTIVE PRINTING OF CERTAIN LINES:
+
+ # print first 10 lines of file (emulates behavior of "head")
+ sed 10q
+
+ # print first line of file (emulates "head -1")
+ sed q
+
+ # print the last 10 lines of a file (emulates "tail")
+ sed -e :a -e '$q;N;11,$D;ba'
+
+ # print the last 2 lines of a file (emulates "tail -2")
+ sed '$!N;$!D'
+
+ # print the last line of a file (emulates "tail -1")
+ sed '$!d'                    # method 1
+ sed -n '$p'                  # method 2
+
+ # print only lines which match regular expression (emulates "grep")
+ sed -n '/regexp/p'           # method 1
+ sed '/regexp/!d'             # method 2
+
+ # print only lines which do NOT match regexp (emulates "grep -v")
+ sed -n '/regexp/!p'          # method 1, corresponds to above
+ sed '/regexp/d'              # method 2, simpler syntax
+
+ # print the line immediately before a regexp, but not the line
+ # containing the regexp
+ sed -n '/regexp/{g;1!p;};h'
+
+ # print the line immediately after a regexp, but not the line
+ # containing the regexp
+ sed -n '/regexp/{n;p;}'
+
+ # print 1 line of context before and after regexp, with line number
+ # indicating where the regexp occurred (similar to "grep -A1 -B1")
+ sed -n -e '/regexp/{=;x;1!p;g;$!N;p;D;}' -e h
+
+ # grep for AAA and BBB and CCC (in any order)
+ sed '/AAA/!d; /BBB/!d; /CCC/!d'
+
+ # grep for AAA and BBB and CCC (in that order)
+ sed '/AAA.*BBB.*CCC/!d'
+
+ # grep for AAA or BBB or CCC (emulates "egrep")
+ sed -e '/AAA/b' -e '/BBB/b' -e '/CCC/b' -e d    # most seds
+ gsed '/AAA\|BBB\|CCC/!d'                        # GNU sed only
+
+ # print paragraph if it contains AAA (blank lines separate paragraphs)
+ # HHsed v1.5 must insert a 'G;' after 'x;' in the next 3 scripts below
+ sed -e '/./{H;$!d;}' -e 'x;/AAA/!d;'
+
+ # print paragraph if it contains AAA and BBB and CCC (in any order)
+ sed -e '/./{H;$!d;}' -e 'x;/AAA/!d;/BBB/!d;/CCC/!d'
+
+ # print paragraph if it contains AAA or BBB or CCC
+ sed -e '/./{H;$!d;}' -e 'x;/AAA/b' -e '/BBB/b' -e '/CCC/b' -e d
+ gsed '/./{H;$!d;};x;/AAA\|BBB\|CCC/b;d'         # GNU sed only
+
+ # print only lines of 65 characters or longer
+ sed -n '/^.\{65\}/p'
+
+ # print only lines of less than 65 characters
+ sed -n '/^.\{65\}/!p'        # method 1, corresponds to above
+ sed '/^.\{65\}/d'            # method 2, simpler syntax
+
+ # print section of file from regular expression to end of file
+ sed -n '/regexp/,$p'
+
+ # print section of file based on line numbers (lines 8-12, inclusive)
+ sed -n '8,12p'               # method 1
+ sed '8,12!d'                 # method 2
+
+ # print line number 52
+ sed -n '52p'                 # method 1
+ sed '52!d'                   # method 2
+ sed '52q;d'                  # method 3, efficient on large files
+
+ # beginning at line 3, print every 7th line
+ gsed -n '3~7p'               # GNU sed only
+ sed -n '3,${p;n;n;n;n;n;n;}' # other seds
+
+ # print section of file between two regular expressions (inclusive)
+ sed -n '/Iowa/,/Montana/p'             # case sensitive
+
+SELECTIVE DELETION OF CERTAIN LINES:
+
+ # print all of file EXCEPT section between 2 regular expressions
+ sed '/Iowa/,/Montana/d'
+
+ # delete duplicate, consecutive lines from a file (emulates "uniq").
+ # First line in a set of duplicate lines is kept, rest are deleted.
+ sed '$!N; /^\(.*\)\n\1$/!P; D'
+
+ # delete duplicate, nonconsecutive lines from a file. Beware not to
+ # overflow the buffer size of the hold space, or else use GNU sed.
+ sed -n 'G; s/\n/&&/; /^\([ -~]*\n\).*\n\1/d; s/\n//; h; P'
+
+ # delete all lines except duplicate lines (emulates "uniq -d").
+ sed '$!N; s/^\(.*\)\n\1$/\1/; t; D'
+
+ # delete the first 10 lines of a file
+ sed '1,10d'
+
+ # delete the last line of a file
+ sed '$d'
+
+ # delete the last 2 lines of a file
+ sed 'N;$!P;$!D;$d'
+
+ # delete the last 10 lines of a file
+ sed -e :a -e '$d;N;2,10ba' -e 'P;D'   # method 1
+ sed -n -e :a -e '1,10!{P;N;D;};N;ba'  # method 2
+
+ # delete every 8th line
+ gsed '0~8d'                           # GNU sed only
+ sed 'n;n;n;n;n;n;n;d;'                # other seds
+
+ # delete ALL blank lines from a file (same as "grep '.' ")
+ sed '/^$/d'                           # method 1
+ sed '/./!d'                           # method 2
+
+ # delete all CONSECUTIVE blank lines from file except the first; also
+ # deletes all blank lines from top and end of file (emulates "cat -s")
+ sed '/./,/^$/!d'          # method 1, allows 0 blanks at top, 1 at EOF
+ sed '/^$/N;/\n$/D'        # method 2, allows 1 blank at top, 0 at EOF
+
+ # delete all CONSECUTIVE blank lines from file except the first 2:
+ sed '/^$/N;/\n$/N;//D'
+
+ # delete all leading blank lines at top of file
+ sed '/./,$!d'
+
+ # delete all trailing blank lines at end of file
+ sed -e :a -e '/^\n*$/{$d;N;ba' -e '}'  # works on all seds
+ sed -e :a -e '/^\n*$/N;/\n$/ba'        # ditto, except for gsed 3.02*
+
+ # delete the last line of each paragraph
+ sed -n '/^$/{p;h;};/./{x;/./p;}'
+
+SPECIAL APPLICATIONS:
+
+ # remove nroff overstrikes (char, backspace) from man pages. The 'echo'
+ # command may need an -e switch if you use Unix System V or bash shell.
+ sed "s/.`echo \\\b`//g"    # double quotes required for Unix environment
+ sed 's/.^H//g'             # in bash/tcsh, press Ctrl-V and then Ctrl-H
+ sed 's/.\x08//g'           # hex expression for sed v1.5
+
+ # get Usenet/e-mail message header
+ sed '/^$/q'                # deletes everything after first blank line
+
+ # get Usenet/e-mail message body
+ sed '1,/^$/d'              # deletes everything up to first blank line
+
+ # get Subject header, but remove initial "Subject: " portion
+ sed '/^Subject: */!d; s///;q'
+
+ # get return address header
+ sed '/^Reply-To:/q; /^From:/h; /./d;g;q'
+
+ # parse out the address proper. Pulls out the e-mail address by itself
+ # from the 1-line return address header (see preceding script)
+ sed 's/ *(.*)//; s/>.*//; s/.*[:<] *//'
+
+ # add a leading angle bracket and space to each line (quote a message)
+ sed 's/^/> /'
+
+ # delete leading angle bracket & space from each line (unquote a message)
+ sed 's/^> //'
+
+ # remove most HTML tags (accommodates multiple-line tags)
+ sed -e :a -e 's/<[^>]*>//g;/</N;//ba'
+
+ # extract multi-part uuencoded binaries, removing extraneous header
+ # info, so that only the uuencoded portion remains. Files passed to
+ # sed must be passed in the proper order. Version 1 can be entered
+ # from the command line; version 2 can be made into an executable
+ # Unix shell script. (Modified from a script by Rahul Dhesi.)
+ sed '/^end/,/^begin/d' file1 file2 ... fileX | uudecode   # vers. 1
+ sed '/^end/,/^begin/d' "$@" | uudecode                    # vers. 2
+
+ # zip up each .TXT file individually, deleting the source file and
+ # setting the name of each .ZIP file to the basename of the .TXT file
+ # (under DOS: the "dir /b" switch returns bare filenames in all caps).
+ echo @echo off >zipup.bat
+ dir /b *.txt | sed "s/^\(.*\)\.TXT/pkzip -mo \1 \1.TXT/" >>zipup.bat
+
+TYPICAL USE: Sed takes one or more editing commands and applies all of
+them, in sequence, to each line of input. After all the commands have
+been applied to the first input line, that line is output and a second
+input line is taken for processing, and the cycle repeats. The
+preceding examples assume that input comes from the standard input
+device (i.e, the console, normally this will be piped input). One or
+more filenames can be appended to the command line if the input does
+not come from stdin. Output is sent to stdout (the screen). Thus:
+
+ cat filename | sed '10q'        # uses piped input
+ sed '10q' filename              # same effect, avoids a useless "cat"
+ sed '10q' filename > newfile    # redirects output to disk
+
+For additional syntax instructions, including the way to apply editing
+commands from a disk file instead of the command line, consult "sed &
+awk, 2nd Edition," by Dale Dougherty and Arnold Robbins (O'Reilly,
+1997; http://www.ora.com), "UNIX Text Processing," by Dale Dougherty
+and Tim O'Reilly (Hayden Books, 1987) or the tutorials by Mike Arst
+distributed in U-SEDIT2.ZIP (many sites). To fully exploit the power
+of sed, one must understand "regular expressions." For this, see
+"Mastering Regular Expressions" by Jeffrey Friedl (O'Reilly, 1997).
+The manual ("man") pages on Unix systems may be helpful (try "man
+sed", "man regexp", or the subsection on regular expressions in "man
+ed"), but man pages are notoriously difficult. They are not written to
+teach sed use or regexps to first-time users, but as a reference text
+for those already acquainted with these tools.
+
+QUOTING SYNTAX: The preceding examples use single quotes ('...')
+instead of double quotes ("...") to enclose editing commands, since
+sed is typically used on a Unix platform. Single quotes prevent the
+Unix shell from intrepreting the dollar sign ($) and backquotes
+(`...`), which are expanded by the shell if they are enclosed in
+double quotes. Users of the "csh" shell and derivatives will also need
+to quote the exclamation mark (!) with the backslash (i.e., \!) to
+properly run the examples listed above, even within single quotes.
+Versions of sed written for DOS invariably require double quotes
+("...") instead of single quotes to enclose editing commands.
+
+USE OF '\t' IN SED SCRIPTS: For clarity in documentation, we have used
+the expression '\t' to indicate a tab character (0x09) in the scripts.
+However, most versions of sed do not recognize the '\t' abbreviation,
+so when typing these scripts from the command line, you should press
+the TAB key instead. '\t' is supported as a regular expression
+metacharacter in awk, perl, and HHsed, sedmod, and GNU sed v3.02.80.
+
+VERSIONS OF SED: Versions of sed do differ, and some slight syntax
+variation is to be expected. In particular, most do not support the
+use of labels (:name) or branch instructions (b,t) within editing
+commands, except at the end of those commands. We have used the syntax
+which will be portable to most users of sed, even though the popular
+GNU versions of sed allow a more succinct syntax. When the reader sees
+a fairly long command such as this:
+
+   sed -e '/AAA/b' -e '/BBB/b' -e '/CCC/b' -e d
+
+it is heartening to know that GNU sed will let you reduce it to:
+
+   sed '/AAA/b;/BBB/b;/CCC/b;d'      # or even
+   sed '/AAA\|BBB\|CCC/b;d'
+
+In addition, remember that while many versions of sed accept a command
+like "/one/ s/RE1/RE2/", some do NOT allow "/one/! s/RE1/RE2/", which
+contains space before the 's'. Omit the space when typing the command.
+
+OPTIMIZING FOR SPEED: If execution speed needs to be increased (due to
+large input files or slow processors or hard disks), substitution will
+be executed more quickly if the "find" expression is specified before
+giving the "s/.../.../" instruction. Thus:
+
+   sed 's/foo/bar/g' filename         # standard replace command
+   sed '/foo/ s/foo/bar/g' filename   # executes more quickly
+   sed '/foo/ s//bar/g' filename      # shorthand sed syntax
+
+On line selection or deletion in which you only need to output lines
+from the first part of the file, a "quit" command (q) in the script
+will drastically reduce processing time for large files. Thus:
+
+   sed -n '45,50p' filename           # print line nos. 45-50 of a file
+   sed -n '51q;45,50p' filename       # same, but executes much faster
+
+If you have any additional scripts to contribute or if you find errors
+in this document, please send e-mail to the compiler. Indicate the
+version of sed you used, the operating system it was compiled for, and
+the nature of the problem. Various scripts in this file were written
+or contributed by:
+
+ Al Aab <af137 at freenet.toronto.on.ca>   # "seders" list moderator
+ Edgar Allen <era at sky.net>              # various
+ Yiorgos Adamopoulos <adamo at softlab.ece.ntua.gr>
+ Dale Dougherty <dale at songline.com>     # author of "sed & awk"
+ Carlos Duarte <cdua at algos.inesc.pt>    # author of "do it with sed"
+ Eric Pement <pemente at northpark.edu>    # author of this document
+ Ken Pizzini <ken at halcyon.com>          # author of GNU sed v3.02
+ S.G. Ravenhall <stew.ravenhall at totalise.co.uk> # great de-html script
+ Greg Ubben <gsu at romulus.ncsc.mil>      # many contributions & much help
+-------------------------------------------------------------------------

Added: trunk/busybox/editors/sed_summary.htm
===================================================================
--- trunk/busybox/editors/sed_summary.htm	                        (rev 0)
+++ trunk/busybox/editors/sed_summary.htm	2007-11-13 17:13:31 UTC (rev 20415)
@@ -0,0 +1,220 @@
+<html>
+
+<head><title>Command Summary for sed (sed & awk, Second Edition)</title>
+</head>
+
+<body>
+
+<h2>Command Summary for sed</h2>
+
+<dl>
+
+<dt><b>: </b> <b> :</b><em>label</em></dt>
+<dd>Label a line in the script for the transfer of control by
+<b>b</b> or <b>t</b>.
+<em>label</em> may contain up to seven characters.
+(The POSIX standard says that an implementation can allow longer
+labels if it wishes to. GNU sed allows labels to be of any length.)
+</p></dd>
+
+
+<dt><b>=</b> [<em>address</em>]<b>=</b></dt>
+<dd>Write to standard output the line number of addressed line.</p></dd>
+
+
+<dt><b>a</b> [<em>address</em>]<b>a\</b></dt>
+<dd><em>text</em></p>
+
+<p>Append <em>text</em>
+following each line matched by <em>address</em>.  If
+<em>text</em> goes over more than one line, newlines
+must be "hidden" by preceding them with a backslash.  The
+<em>text</em> will be terminated by the first
+newline that is not hidden in this way.  The
+<em>text</em> is not available in the pattern space
+and subsequent commands cannot be applied to it.  The results of this
+command are sent to standard output when the list of editing commands
+is finished, regardless of what happens to the current line in the
+pattern space.</p></dd>
+
+
+<dt><b>b</b> [<em>address1</em>[,<em>address2</em>]]<b>b</b>[<em>label</em>]</dt>
+<dd>Transfer control unconditionally (branch) to
+<b>:</b><em>label</em> elsewhere in
+script.  That is, the command following the
+<em>label</em> is the next command applied to the
+current line.  If no <em>label</em> is specified,
+control falls through to the end of the script, so no more commands
+are applied to the current line.</p></dd>
+
+
+<dt><b>c</b> [<em>address1</em>[,<em>address2</em>]]<b>c\</b></dt>
+<dd><em>text</em></p>
+
+<p>Replace (change) the lines selected by the address with
+<em>text</em>.  When a range of lines is specified,
+all lines as a group are replaced by a single copy of
+<em>text</em>.  The newline following each line of
+<em>text</em> must be escaped by a backslash, except
+the last line.  The contents of the pattern space are, in effect,
+deleted and no subsequent editing commands can be applied to it (or to
+<em>text</em>).</p></dd>
+
+
+<dt><b>d</b> [<em>address1</em>[,<em>address2</em>]]<b>d</b></dt>
+<dd>Delete line(s) from pattern space.  Thus, the line is not passed to standard
+output. A new line of input is read and editing resumes with first
+command in script.</p></dd>
+
+
+<dt><b>D</b> [<em>address1</em>[,<em>address2</em>]]<b>D</b></dt>
+<dd>Delete first part (up to embedded newline) of multiline pattern space created
+by <b>N</b> command and resume editing with first command in
+script.  If this command empties the pattern space, then a new line
+of input is read, as if the <b>d</b> command had been executed.</p></dd>
+
+
+<dt><b>g</b> [<em>address1</em>[,<em>address2</em>]]<b>g</b></dt>
+<dd>Copy (get) contents of hold space (see <b>h</b> or
+<b>H</b> command) into the pattern space, wiping out
+previous contents.</p></dd>
+
+
+<dt><b>G</b> [<em>address1</em>[,<em>address2</em>]]<b>G</b></dt>
+<dd>Append newline followed by contents of hold space (see
+<b>h</b> or <b>H</b> command) to contents of
+the pattern space.  If hold space is empty, a newline is still
+appended to the pattern space.</p></dd>
+
+
+<dt><b>h</b> [<em>address1</em>[,<em>address2</em>]]<b>h</b></dt>
+<dd>Copy pattern space into hold space, a special temporary buffer.
+Previous contents of hold space are wiped out.</p></dd>
+
+
+<dt><b>H</b> [<em>address1</em>[,<em>address2</em>]]<b>H</b></dt>
+<dd>Append newline and contents of pattern space to contents of the hold
+space.  Even if hold space is empty, this command still appends the
+newline first.</p></dd>
+
+
+<dt><b>i</b> [<em>address1</em>]<b>i\</b></dt>
+<dd><em>text</em></p>
+
+<p>Insert <em>text</em> before each line matched by
+<em>address</em>. (See <b>a</b> for
+details on <em>text</em>.)</p></dd>
+
+
+<dt><b>l</b> [<em>address1</em>[,<em>address2</em>]]<b>l</b></dt>
+<dd>List the contents of the pattern space, showing nonprinting characters
+as ASCII codes.  Long lines are wrapped.</p></dd>
+
+
+<dt><b>n</b> [<em>address1</em>[,<em>address2</em>]]<b>n</b></dt>
+<dd>Read next line of input into pattern space.  Current line is sent to
+standard output.  New line becomes current line and increments line
+counter.  Control passes to command following <b>n</b>
+instead of resuming at the top of the script.</p></dd>
+
+
+<dt><b>N</b> [<em>address1</em>[,<em>address2</em>]]<b>N</b></dt>
+<dd>Append next input line to contents of pattern space; the new line is
+separated from the previous contents of the pattern space by a newline.  
+(This command is designed to allow pattern matches across two
+lines.  Using \n to match the embedded newline, you can match
+patterns across multiple lines.)</p></dd>
+
+
+<dt><b>p</b> [<em>address1</em>[,<em>address2</em>]]<b>p</b></dt>
+<dd>Print the addressed line(s).  Note that this can result in duplicate
+output unless default output is suppressed by using "#n" or
+the <span class="option">-n</span>
+
+command-line option.  Typically used before commands that change flow
+control (<b>d</b>, <b>n</b>,
+<b>b</b>) and might prevent the current line from being
+output.</p></dd>
+
+
+<dt><b>P</b> [<em>address1</em>[,<em>address2</em>]]<b>P</b></dt>
+<dd>Print first part (up to embedded newline) of multiline pattern space
+created by <b>N</b> command.  Same as <b>p</b>
+if <b>N</b> has not been applied to a line.</p></dd>
+
+
+<dt><b>q</b> [<em>address</em>]<b>q</b></dt>
+<dd>Quit when <em>address</em> is encountered.  The
+addressed line is first written to output (if default output is not
+suppressed), along with any text appended to it by previous
+<b>a</b> or <b>r</b> commands.</p></dd>
+
+
+<dt><b>r</b> [<em>address</em>]<b>r</b> <em>file</em></dt>
+<dd>Read contents of <em>file</em> and append after the
+contents of the pattern space.  Exactly one space must be put between
+<b>r</b> and the filename.</p></dd>
+
+
+<dt><b>s</b> [<em>address1</em>[,<em>address2</em>]]<b>s</b>/<em>pattern</em>/<em>replacement</em>/[<em>flags</em>]</dt>
+<dd>Substitute <em>replacement</em> for
+<em>pattern</em> on each addressed line.  If pattern
+addresses are used, the pattern <b>//</b> represents the
+last pattern address specified.  The following flags can be specified:</p>
+
+	<dl>
+
+	<dt><b>n</b></dt>
+	<dd>Replace <em>n</em>th instance of
+	/<em>pattern</em>/ on each addressed line.
+	<em>n</em> is any number in the range 1 to 512, and
+	the default is 1.</p></dd>
+
+	<dt><b>g</b></dt>
+	<dd>Replace all instances of /<em>pattern</em>/ on each
+	addressed line, not just the first instance.</p></dd>
+
+	<dt><b>p</b></dt>
+	<dd>Print the line if a successful substitution is done.  If several
+	successful substitutions are done, multiple copies of the line will be
+	printed.</p></dd>
+
+	<dt><b>w</b> <em>file</em></dt>
+	<dd>Write the line to <em>file</em> if a replacement
+	was done.  A maximum of 10 different <em>files</em> can be opened.</p></dd>
+
+	</dl>
+
+</dd>
+
+
+<dt><b>t</b> [<em>address1</em>[,<em>address2</em>]]<b>t </b>[<em>label</em>]</dt>
+<dd>Test if successful substitutions have been made on addressed lines,
+and if so, branch to line marked by :<em>label</em>.
+(See <b>b</b> and <b>:</b>.)  If label is not
+specified, control falls through to bottom of script.</p></dd>
+
+
+<dt><b>w</b> [<em>address1</em>[,<em>address2</em>]]<b>w</b> <em>file</em></dt>
+<dd>Append contents of pattern space to <em>file</em>.
+This action occurs when the command is encountered rather than when
+the pattern space is output.  Exactly one space must separate the
+<b>w</b> and the filename.  A maximum of 10 different
+files can be opened in a script.  This command will create the file if
+it does not exist; if the file exists, its contents will be
+overwritten each time the script is executed.  Multiple write commands
+that direct output to the same file append to the end of the file.</p></dd>
+
+
+<dt><b>x</b> [<em>address1</em>[,<em>address2</em>]]<b>x</b></dt>
+<dd>Exchange contents of the pattern space with the contents of the hold
+space.</p></dd>
+
+
+<dt><b>y</b> [<em>address1</em>[,<em>address2</em>]]<b>y</b>/<em>abc</em>/<em>xyz</em>/</dt>
+<dd>Transform each character by position in string
+<em>abc</em> to its equivalent in string
+<em>xyz</em>.</p></dd>
+
+
+</dl>




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