1http://www.student.northpark.edu/pemente/sed/sed1line.txt
2-------------------------------------------------------------------------
3HANDY ONE-LINERS FOR SED (Unix stream editor)               Apr. 26, 2004
4compiled by Eric Pement - pemente[at]northpark[dot]edu        version 5.4
5Latest version of this file is usually at:
6   http://sed.sourceforge.net/sed1line.txt
7   http://www.student.northpark.edu/pemente/sed/sed1line.txt
8This file is also available in Portuguese at:
9   http://www.lrv.ufsc.br/wmaker/sed_ptBR.html
10
11FILE SPACING:
12
13 # double space a file
14 sed G
15
16 # double space a file which already has blank lines in it. Output file
17 # should contain no more than one blank line between lines of text.
18 sed '/^$/d;G'
19
20 # triple space a file
21 sed 'G;G'
22
23 # undo double-spacing (assumes even-numbered lines are always blank)
24 sed 'n;d'
25
26 # insert a blank line above every line which matches "regex"
27 sed '/regex/{x;p;x;}'
28
29 # insert a blank line below every line which matches "regex"
30 sed '/regex/G'
31
32 # insert a blank line above and below every line which matches "regex"
33 sed '/regex/{x;p;x;G;}'
34
35NUMBERING:
36
37 # number each line of a file (simple left alignment). Using a tab (see
38 # note on '\t' at end of file) instead of space will preserve margins.
39 sed = filename | sed 'N;s/\n/\t/'
40
41 # number each line of a file (number on left, right-aligned)
42 sed = filename | sed 'N; s/^/     /; s/ *\(.\{6,\}\)\n/\1  /'
43
44 # number each line of file, but only print numbers if line is not blank
45 sed '/./=' filename | sed '/./N; s/\n/ /'
46
47 # count lines (emulates "wc -l")
48 sed -n '$='
49
50TEXT CONVERSION AND SUBSTITUTION:
51
52 # IN UNIX ENVIRONMENT: convert DOS newlines (CR/LF) to Unix format
53 sed 's/.$//'               # assumes that all lines end with CR/LF
54 sed 's/^M$//'              # in bash/tcsh, press Ctrl-V then Ctrl-M
55 sed 's/\x0D$//'            # gsed 3.02.80, but top script is easier
56
57 # IN UNIX ENVIRONMENT: convert Unix newlines (LF) to DOS format
58 sed "s/$/`echo -e \\\r`/"            # command line under ksh
59 sed 's/$'"/`echo \\\r`/"             # command line under bash
60 sed "s/$/`echo \\\r`/"               # command line under zsh
61 sed 's/$/\r/'                        # gsed 3.02.80
62
63 # IN DOS ENVIRONMENT: convert Unix newlines (LF) to DOS format
64 sed "s/$//"                          # method 1
65 sed -n p                             # method 2
66
67 # IN DOS ENVIRONMENT: convert DOS newlines (CR/LF) to Unix format
68 # Can only be done with UnxUtils sed, version 4.0.7 or higher.
69 # Cannot be done with other DOS versions of sed. Use "tr" instead.
70 sed "s/\r//" infile >outfile         # UnxUtils sed v4.0.7 or higher
71 tr -d \r <infile >outfile            # GNU tr version 1.22 or higher
72
73 # delete leading whitespace (spaces, tabs) from front of each line
74 # aligns all text flush left
75 sed 's/^[ \t]*//'                    # see note on '\t' at end of file
76
77 # delete trailing whitespace (spaces, tabs) from end of each line
78 sed 's/[ \t]*$//'                    # see note on '\t' at end of file
79
80 # delete BOTH leading and trailing whitespace from each line
81 sed 's/^[ \t]*//;s/[ \t]*$//'
82
83 # insert 5 blank spaces at beginning of each line (make page offset)
84 sed 's/^/     /'
85
86 # align all text flush right on a 79-column width
87 sed -e :a -e 's/^.\{1,78\}$/ &/;ta'  # set at 78 plus 1 space
88
89 # center all text in the middle of 79-column width. In method 1,
90 # spaces at the beginning of the line are significant, and trailing
91 # spaces are appended at the end of the line. In method 2, spaces at
92 # the beginning of the line are discarded in centering the line, and
93 # no trailing spaces appear at the end of lines.
94 sed  -e :a -e 's/^.\{1,77\}$/ & /;ta'                     # method 1
95 sed  -e :a -e 's/^.\{1,77\}$/ &/;ta' -e 's/\( *\)\1/\1/'  # method 2
96
97 # substitute (find and replace) "foo" with "bar" on each line
98 sed 's/foo/bar/'             # replaces only 1st instance in a line
99 sed 's/foo/bar/4'            # replaces only 4th instance in a line
100 sed 's/foo/bar/g'            # replaces ALL instances in a line
101 sed 's/\(.*\)foo\(.*foo\)/\1bar\2/' # replace the next-to-last case
102 sed 's/\(.*\)foo/\1bar/'            # replace only the last case
103
104 # substitute "foo" with "bar" ONLY for lines which contain "baz"
105 sed '/baz/s/foo/bar/g'
106
107 # substitute "foo" with "bar" EXCEPT for lines which contain "baz"
108 sed '/baz/!s/foo/bar/g'
109
110 # change "scarlet" or "ruby" or "puce" to "red"
111 sed 's/scarlet/red/g;s/ruby/red/g;s/puce/red/g'   # most seds
112 gsed 's/scarlet\|ruby\|puce/red/g'                # GNU sed only
113
114 # reverse order of lines (emulates "tac")
115 # bug/feature in HHsed v1.5 causes blank lines to be deleted
116 sed '1!G;h;$!d'               # method 1
117 sed -n '1!G;h;$p'             # method 2
118
119 # reverse each character on the line (emulates "rev")
120 sed '/\n/!G;s/\(.\)\(.*\n\)/&\2\1/;//D;s/.//'
121
122 # join pairs of lines side-by-side (like "paste")
123 sed '$!N;s/\n/ /'
124
125 # if a line ends with a backslash, append the next line to it
126 sed -e :a -e '/\\$/N; s/\\\n//; ta'
127
128 # if a line begins with an equal sign, append it to the previous line
129 # and replace the "=" with a single space
130 sed -e :a -e '$!N;s/\n=/ /;ta' -e 'P;D'
131
132 # add commas to numeric strings, changing "1234567" to "1,234,567"
133 gsed ':a;s/\B[0-9]\{3\}\>/,&/;ta'                     # GNU sed
134 sed -e :a -e 's/\(.*[0-9]\)\([0-9]\{3\}\)/\1,\2/;ta'  # other seds
135
136 # add commas to numbers with decimal points and minus signs (GNU sed)
137 gsed ':a;s/\(^\|[^0-9.]\)\([0-9]\+\)\([0-9]\{3\}\)/\1\2,\3/g;ta'
138
139 # add a blank line every 5 lines (after lines 5, 10, 15, 20, etc.)
140 gsed '0~5G'                  # GNU sed only
141 sed 'n;n;n;n;G;'             # other seds
142
143SELECTIVE PRINTING OF CERTAIN LINES:
144
145 # print first 10 lines of file (emulates behavior of "head")
146 sed 10q
147
148 # print first line of file (emulates "head -1")
149 sed q
150
151 # print the last 10 lines of a file (emulates "tail")
152 sed -e :a -e '$q;N;11,$D;ba'
153
154 # print the last 2 lines of a file (emulates "tail -2")
155 sed '$!N;$!D'
156
157 # print the last line of a file (emulates "tail -1")
158 sed '$!d'                    # method 1
159 sed -n '$p'                  # method 2
160
161 # print only lines which match regular expression (emulates "grep")
162 sed -n '/regexp/p'           # method 1
163 sed '/regexp/!d'             # method 2
164
165 # print only lines which do NOT match regexp (emulates "grep -v")
166 sed -n '/regexp/!p'          # method 1, corresponds to above
167 sed '/regexp/d'              # method 2, simpler syntax
168
169 # print the line immediately before a regexp, but not the line
170 # containing the regexp
171 sed -n '/regexp/{g;1!p;};h'
172
173 # print the line immediately after a regexp, but not the line
174 # containing the regexp
175 sed -n '/regexp/{n;p;}'
176
177 # print 1 line of context before and after regexp, with line number
178 # indicating where the regexp occurred (similar to "grep -A1 -B1")
179 sed -n -e '/regexp/{=;x;1!p;g;$!N;p;D;}' -e h
180
181 # grep for AAA and BBB and CCC (in any order)
182 sed '/AAA/!d; /BBB/!d; /CCC/!d'
183
184 # grep for AAA and BBB and CCC (in that order)
185 sed '/AAA.*BBB.*CCC/!d'
186
187 # grep for AAA or BBB or CCC (emulates "egrep")
188 sed -e '/AAA/b' -e '/BBB/b' -e '/CCC/b' -e d    # most seds
189 gsed '/AAA\|BBB\|CCC/!d'                        # GNU sed only
190
191 # print paragraph if it contains AAA (blank lines separate paragraphs)
192 # HHsed v1.5 must insert a 'G;' after 'x;' in the next 3 scripts below
193 sed -e '/./{H;$!d;}' -e 'x;/AAA/!d;'
194
195 # print paragraph if it contains AAA and BBB and CCC (in any order)
196 sed -e '/./{H;$!d;}' -e 'x;/AAA/!d;/BBB/!d;/CCC/!d'
197
198 # print paragraph if it contains AAA or BBB or CCC
199 sed -e '/./{H;$!d;}' -e 'x;/AAA/b' -e '/BBB/b' -e '/CCC/b' -e d
200 gsed '/./{H;$!d;};x;/AAA\|BBB\|CCC/b;d'         # GNU sed only
201
202 # print only lines of 65 characters or longer
203 sed -n '/^.\{65\}/p'
204
205 # print only lines of less than 65 characters
206 sed -n '/^.\{65\}/!p'        # method 1, corresponds to above
207 sed '/^.\{65\}/d'            # method 2, simpler syntax
208
209 # print section of file from regular expression to end of file
210 sed -n '/regexp/,$p'
211
212 # print section of file based on line numbers (lines 8-12, inclusive)
213 sed -n '8,12p'               # method 1
214 sed '8,12!d'                 # method 2
215
216 # print line number 52
217 sed -n '52p'                 # method 1
218 sed '52!d'                   # method 2
219 sed '52q;d'                  # method 3, efficient on large files
220
221 # beginning at line 3, print every 7th line
222 gsed -n '3~7p'               # GNU sed only
223 sed -n '3,${p;n;n;n;n;n;n;}' # other seds
224
225 # print section of file between two regular expressions (inclusive)
226 sed -n '/Iowa/,/Montana/p'             # case sensitive
227
228SELECTIVE DELETION OF CERTAIN LINES:
229
230 # print all of file EXCEPT section between 2 regular expressions
231 sed '/Iowa/,/Montana/d'
232
233 # delete duplicate, consecutive lines from a file (emulates "uniq").
234 # First line in a set of duplicate lines is kept, rest are deleted.
235 sed '$!N; /^\(.*\)\n\1$/!P; D'
236
237 # delete duplicate, nonconsecutive lines from a file. Beware not to
238 # overflow the buffer size of the hold space, or else use GNU sed.
239 sed -n 'G; s/\n/&&/; /^\([ -~]*\n\).*\n\1/d; s/\n//; h; P'
240
241 # delete all lines except duplicate lines (emulates "uniq -d").
242 sed '$!N; s/^\(.*\)\n\1$/\1/; t; D'
243
244 # delete the first 10 lines of a file
245 sed '1,10d'
246
247 # delete the last line of a file
248 sed '$d'
249
250 # delete the last 2 lines of a file
251 sed 'N;$!P;$!D;$d'
252
253 # delete the last 10 lines of a file
254 sed -e :a -e '$d;N;2,10ba' -e 'P;D'   # method 1
255 sed -n -e :a -e '1,10!{P;N;D;};N;ba'  # method 2
256
257 # delete every 8th line
258 gsed '0~8d'                           # GNU sed only
259 sed 'n;n;n;n;n;n;n;d;'                # other seds
260
261 # delete ALL blank lines from a file (same as "grep '.' ")
262 sed '/^$/d'                           # method 1
263 sed '/./!d'                           # method 2
264
265 # delete all CONSECUTIVE blank lines from file except the first; also
266 # deletes all blank lines from top and end of file (emulates "cat -s")
267 sed '/./,/^$/!d'          # method 1, allows 0 blanks at top, 1 at EOF
268 sed '/^$/N;/\n$/D'        # method 2, allows 1 blank at top, 0 at EOF
269
270 # delete all CONSECUTIVE blank lines from file except the first 2:
271 sed '/^$/N;/\n$/N;//D'
272
273 # delete all leading blank lines at top of file
274 sed '/./,$!d'
275
276 # delete all trailing blank lines at end of file
277 sed -e :a -e '/^\n*$/{$d;N;ba' -e '}'  # works on all seds
278 sed -e :a -e '/^\n*$/N;/\n$/ba'        # ditto, except for gsed 3.02*
279
280 # delete the last line of each paragraph
281 sed -n '/^$/{p;h;};/./{x;/./p;}'
282
283SPECIAL APPLICATIONS:
284
285 # remove nroff overstrikes (char, backspace) from man pages. The 'echo'
286 # command may need an -e switch if you use Unix System V or bash shell.
287 sed "s/.`echo \\\b`//g"    # double quotes required for Unix environment
288 sed 's/.^H//g'             # in bash/tcsh, press Ctrl-V and then Ctrl-H
289 sed 's/.\x08//g'           # hex expression for sed v1.5
290
291 # get Usenet/e-mail message header
292 sed '/^$/q'                # deletes everything after first blank line
293
294 # get Usenet/e-mail message body
295 sed '1,/^$/d'              # deletes everything up to first blank line
296
297 # get Subject header, but remove initial "Subject: " portion
298 sed '/^Subject: */!d; s///;q'
299
300 # get return address header
301 sed '/^Reply-To:/q; /^From:/h; /./d;g;q'
302
303 # parse out the address proper. Pulls out the e-mail address by itself
304 # from the 1-line return address header (see preceding script)
305 sed 's/ *(.*)//; s/>.*//; s/.*[:<] *//'
306
307 # add a leading angle bracket and space to each line (quote a message)
308 sed 's/^/> /'
309
310 # delete leading angle bracket & space from each line (unquote a message)
311 sed 's/^> //'
312
313 # remove most HTML tags (accommodates multiple-line tags)
314 sed -e :a -e 's/<[^>]*>//g;/</N;//ba'
315
316 # extract multi-part uuencoded binaries, removing extraneous header
317 # info, so that only the uuencoded portion remains. Files passed to
318 # sed must be passed in the proper order. Version 1 can be entered
319 # from the command line; version 2 can be made into an executable
320 # Unix shell script. (Modified from a script by Rahul Dhesi.)
321 sed '/^end/,/^begin/d' file1 file2 ... fileX | uudecode   # vers. 1
322 sed '/^end/,/^begin/d' "$@" | uudecode                    # vers. 2
323
324 # zip up each .TXT file individually, deleting the source file and
325 # setting the name of each .ZIP file to the basename of the .TXT file
326 # (under DOS: the "dir /b" switch returns bare filenames in all caps).
327 echo @echo off >zipup.bat
328 dir /b *.txt | sed "s/^\(.*\)\.TXT/pkzip -mo \1 \1.TXT/" >>zipup.bat
329
330TYPICAL USE: Sed takes one or more editing commands and applies all of
331them, in sequence, to each line of input. After all the commands have
332been applied to the first input line, that line is output and a second
333input line is taken for processing, and the cycle repeats. The
334preceding examples assume that input comes from the standard input
335device (i.e, the console, normally this will be piped input). One or
336more filenames can be appended to the command line if the input does
337not come from stdin. Output is sent to stdout (the screen). Thus:
338
339 cat filename | sed '10q'        # uses piped input
340 sed '10q' filename              # same effect, avoids a useless "cat"
341 sed '10q' filename > newfile    # redirects output to disk
342
343For additional syntax instructions, including the way to apply editing
344commands from a disk file instead of the command line, consult "sed &
345awk, 2nd Edition," by Dale Dougherty and Arnold Robbins (O'Reilly,
3461997; http://www.ora.com), "UNIX Text Processing," by Dale Dougherty
347and Tim O'Reilly (Hayden Books, 1987) or the tutorials by Mike Arst
348distributed in U-SEDIT2.ZIP (many sites). To fully exploit the power
349of sed, one must understand "regular expressions." For this, see
350"Mastering Regular Expressions" by Jeffrey Friedl (O'Reilly, 1997).
351The manual ("man") pages on Unix systems may be helpful (try "man
352sed", "man regexp", or the subsection on regular expressions in "man
353ed"), but man pages are notoriously difficult. They are not written to
354teach sed use or regexps to first-time users, but as a reference text
355for those already acquainted with these tools.
356
357QUOTING SYNTAX: The preceding examples use single quotes ('...')
358instead of double quotes ("...") to enclose editing commands, since
359sed is typically used on a Unix platform. Single quotes prevent the
360Unix shell from intrepreting the dollar sign ($) and backquotes
361(`...`), which are expanded by the shell if they are enclosed in
362double quotes. Users of the "csh" shell and derivatives will also need
363to quote the exclamation mark (!) with the backslash (i.e., \!) to
364properly run the examples listed above, even within single quotes.
365Versions of sed written for DOS invariably require double quotes
366("...") instead of single quotes to enclose editing commands.
367
368USE OF '\t' IN SED SCRIPTS: For clarity in documentation, we have used
369the expression '\t' to indicate a tab character (0x09) in the scripts.
370However, most versions of sed do not recognize the '\t' abbreviation,
371so when typing these scripts from the command line, you should press
372the TAB key instead. '\t' is supported as a regular expression
373metacharacter in awk, perl, and HHsed, sedmod, and GNU sed v3.02.80.
374
375VERSIONS OF SED: Versions of sed do differ, and some slight syntax
376variation is to be expected. In particular, most do not support the
377use of labels (:name) or branch instructions (b,t) within editing
378commands, except at the end of those commands. We have used the syntax
379which will be portable to most users of sed, even though the popular
380GNU versions of sed allow a more succinct syntax. When the reader sees
381a fairly long command such as this:
382
383   sed -e '/AAA/b' -e '/BBB/b' -e '/CCC/b' -e d
384
385it is heartening to know that GNU sed will let you reduce it to:
386
387   sed '/AAA/b;/BBB/b;/CCC/b;d'      # or even
388   sed '/AAA\|BBB\|CCC/b;d'
389
390In addition, remember that while many versions of sed accept a command
391like "/one/ s/RE1/RE2/", some do NOT allow "/one/! s/RE1/RE2/", which
392contains space before the 's'. Omit the space when typing the command.
393
394OPTIMIZING FOR SPEED: If execution speed needs to be increased (due to
395large input files or slow processors or hard disks), substitution will
396be executed more quickly if the "find" expression is specified before
397giving the "s/.../.../" instruction. Thus:
398
399   sed 's/foo/bar/g' filename         # standard replace command
400   sed '/foo/ s/foo/bar/g' filename   # executes more quickly
401   sed '/foo/ s//bar/g' filename      # shorthand sed syntax
402
403On line selection or deletion in which you only need to output lines
404from the first part of the file, a "quit" command (q) in the script
405will drastically reduce processing time for large files. Thus:
406
407   sed -n '45,50p' filename           # print line nos. 45-50 of a file
408   sed -n '51q;45,50p' filename       # same, but executes much faster
409
410If you have any additional scripts to contribute or if you find errors
411in this document, please send e-mail to the compiler. Indicate the
412version of sed you used, the operating system it was compiled for, and
413the nature of the problem. Various scripts in this file were written
414or contributed by:
415
416 Al Aab <af137@freenet.toronto.on.ca>   # "seders" list moderator
417 Edgar Allen <era@sky.net>              # various
418 Yiorgos Adamopoulos <adamo@softlab.ece.ntua.gr>
419 Dale Dougherty <dale@songline.com>     # author of "sed & awk"
420 Carlos Duarte <cdua@algos.inesc.pt>    # author of "do it with sed"
421 Eric Pement <pemente@northpark.edu>    # author of this document
422 Ken Pizzini <ken@halcyon.com>          # author of GNU sed v3.02
423 S.G. Ravenhall <stew.ravenhall@totalise.co.uk> # great de-html script
424 Greg Ubben <gsu@romulus.ncsc.mil>      # many contributions & much help
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