| 1 | http://www.student.northpark.edu/pemente/sed/sed1line.txt
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| 2 | -------------------------------------------------------------------------
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| 3 | HANDY ONE-LINERS FOR SED (Unix stream editor) Apr. 26, 2004
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| 4 | compiled by Eric Pement - pemente[at]northpark[dot]edu version 5.4
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| 5 | Latest version of this file is usually at:
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| 6 | http://sed.sourceforge.net/sed1line.txt
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| 7 | http://www.student.northpark.edu/pemente/sed/sed1line.txt
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| 8 | This file is also available in Portuguese at:
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| 9 | http://www.lrv.ufsc.br/wmaker/sed_ptBR.html
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| 10 |
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| 11 | FILE SPACING:
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| 12 |
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| 13 | # double space a file
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| 14 | sed G
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| 15 |
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| 16 | # double space a file which already has blank lines in it. Output file
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| 17 | # should contain no more than one blank line between lines of text.
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| 18 | sed '/^$/d;G'
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| 19 |
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| 20 | # triple space a file
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| 21 | sed 'G;G'
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| 22 |
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| 23 | # undo double-spacing (assumes even-numbered lines are always blank)
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| 24 | sed 'n;d'
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| 25 |
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| 26 | # insert a blank line above every line which matches "regex"
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| 27 | sed '/regex/{x;p;x;}'
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| 28 |
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| 29 | # insert a blank line below every line which matches "regex"
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| 30 | sed '/regex/G'
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| 31 |
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| 32 | # insert a blank line above and below every line which matches "regex"
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| 33 | sed '/regex/{x;p;x;G;}'
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| 34 |
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| 35 | NUMBERING:
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| 36 |
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| 37 | # number each line of a file (simple left alignment). Using a tab (see
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| 38 | # note on '\t' at end of file) instead of space will preserve margins.
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| 39 | sed = filename | sed 'N;s/\n/\t/'
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| 40 |
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| 41 | # number each line of a file (number on left, right-aligned)
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| 42 | sed = filename | sed 'N; s/^/ /; s/ *\(.\{6,\}\)\n/\1 /'
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| 43 |
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| 44 | # number each line of file, but only print numbers if line is not blank
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| 45 | sed '/./=' filename | sed '/./N; s/\n/ /'
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| 46 |
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| 47 | # count lines (emulates "wc -l")
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| 48 | sed -n '$='
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| 49 |
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| 50 | TEXT CONVERSION AND SUBSTITUTION:
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| 51 |
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| 52 | # IN UNIX ENVIRONMENT: convert DOS newlines (CR/LF) to Unix format
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| 53 | sed 's/.$//' # assumes that all lines end with CR/LF
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| 54 | sed 's/^M$//' # in bash/tcsh, press Ctrl-V then Ctrl-M
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| 55 | sed 's/\x0D$//' # gsed 3.02.80, but top script is easier
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| 56 |
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| 57 | # IN UNIX ENVIRONMENT: convert Unix newlines (LF) to DOS format
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| 58 | sed "s/$/`echo -e \\\r`/" # command line under ksh
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| 59 | sed 's/$'"/`echo \\\r`/" # command line under bash
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| 60 | sed "s/$/`echo \\\r`/" # command line under zsh
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| 61 | sed 's/$/\r/' # gsed 3.02.80
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| 62 |
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| 63 | # IN DOS ENVIRONMENT: convert Unix newlines (LF) to DOS format
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| 64 | sed "s/$//" # method 1
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| 65 | sed -n p # method 2
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| 66 |
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| 67 | # IN DOS ENVIRONMENT: convert DOS newlines (CR/LF) to Unix format
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| 68 | # Can only be done with UnxUtils sed, version 4.0.7 or higher.
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| 69 | # Cannot be done with other DOS versions of sed. Use "tr" instead.
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| 70 | sed "s/\r//" infile >outfile # UnxUtils sed v4.0.7 or higher
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| 71 | tr -d \r <infile >outfile # GNU tr version 1.22 or higher
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| 72 |
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| 73 | # delete leading whitespace (spaces, tabs) from front of each line
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| 74 | # aligns all text flush left
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| 75 | sed 's/^[ \t]*//' # see note on '\t' at end of file
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| 76 |
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| 77 | # delete trailing whitespace (spaces, tabs) from end of each line
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| 78 | sed 's/[ \t]*$//' # see note on '\t' at end of file
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| 79 |
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| 80 | # delete BOTH leading and trailing whitespace from each line
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| 81 | sed 's/^[ \t]*//;s/[ \t]*$//'
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| 82 |
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| 83 | # insert 5 blank spaces at beginning of each line (make page offset)
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| 84 | sed 's/^/ /'
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| 85 |
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| 86 | # align all text flush right on a 79-column width
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| 87 | sed -e :a -e 's/^.\{1,78\}$/ &/;ta' # set at 78 plus 1 space
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| 88 |
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| 89 | # center all text in the middle of 79-column width. In method 1,
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| 90 | # spaces at the beginning of the line are significant, and trailing
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| 91 | # spaces are appended at the end of the line. In method 2, spaces at
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| 92 | # the beginning of the line are discarded in centering the line, and
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| 93 | # no trailing spaces appear at the end of lines.
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| 94 | sed -e :a -e 's/^.\{1,77\}$/ & /;ta' # method 1
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| 95 | sed -e :a -e 's/^.\{1,77\}$/ &/;ta' -e 's/\( *\)\1/\1/' # method 2
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| 96 |
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| 97 | # substitute (find and replace) "foo" with "bar" on each line
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| 98 | sed 's/foo/bar/' # replaces only 1st instance in a line
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| 99 | sed 's/foo/bar/4' # replaces only 4th instance in a line
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| 100 | sed 's/foo/bar/g' # replaces ALL instances in a line
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| 101 | sed 's/\(.*\)foo\(.*foo\)/\1bar\2/' # replace the next-to-last case
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| 102 | sed 's/\(.*\)foo/\1bar/' # replace only the last case
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| 103 |
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| 104 | # substitute "foo" with "bar" ONLY for lines which contain "baz"
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| 105 | sed '/baz/s/foo/bar/g'
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| 106 |
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| 107 | # substitute "foo" with "bar" EXCEPT for lines which contain "baz"
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| 108 | sed '/baz/!s/foo/bar/g'
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| 109 |
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| 110 | # change "scarlet" or "ruby" or "puce" to "red"
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| 111 | sed 's/scarlet/red/g;s/ruby/red/g;s/puce/red/g' # most seds
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| 112 | gsed 's/scarlet\|ruby\|puce/red/g' # GNU sed only
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| 113 |
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| 114 | # reverse order of lines (emulates "tac")
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| 115 | # bug/feature in HHsed v1.5 causes blank lines to be deleted
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| 116 | sed '1!G;h;$!d' # method 1
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| 117 | sed -n '1!G;h;$p' # method 2
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| 118 |
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| 119 | # reverse each character on the line (emulates "rev")
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| 120 | sed '/\n/!G;s/\(.\)\(.*\n\)/&\2\1/;//D;s/.//'
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| 121 |
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| 122 | # join pairs of lines side-by-side (like "paste")
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| 123 | sed '$!N;s/\n/ /'
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| 124 |
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| 125 | # if a line ends with a backslash, append the next line to it
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| 126 | sed -e :a -e '/\\$/N; s/\\\n//; ta'
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| 127 |
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| 128 | # if a line begins with an equal sign, append it to the previous line
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| 129 | # and replace the "=" with a single space
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| 130 | sed -e :a -e '$!N;s/\n=/ /;ta' -e 'P;D'
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| 131 |
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| 132 | # add commas to numeric strings, changing "1234567" to "1,234,567"
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| 133 | gsed ':a;s/\B[0-9]\{3\}\>/,&/;ta' # GNU sed
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| 134 | sed -e :a -e 's/\(.*[0-9]\)\([0-9]\{3\}\)/\1,\2/;ta' # other seds
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| 135 |
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| 136 | # add commas to numbers with decimal points and minus signs (GNU sed)
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| 137 | gsed ':a;s/\(^\|[^0-9.]\)\([0-9]\+\)\([0-9]\{3\}\)/\1\2,\3/g;ta'
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| 138 |
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| 139 | # add a blank line every 5 lines (after lines 5, 10, 15, 20, etc.)
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| 140 | gsed '0~5G' # GNU sed only
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| 141 | sed 'n;n;n;n;G;' # other seds
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| 142 |
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| 143 | SELECTIVE PRINTING OF CERTAIN LINES:
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| 144 |
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| 145 | # print first 10 lines of file (emulates behavior of "head")
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| 146 | sed 10q
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| 147 |
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| 148 | # print first line of file (emulates "head -1")
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| 149 | sed q
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| 150 |
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| 151 | # print the last 10 lines of a file (emulates "tail")
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| 152 | sed -e :a -e '$q;N;11,$D;ba'
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| 153 |
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| 154 | # print the last 2 lines of a file (emulates "tail -2")
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| 155 | sed '$!N;$!D'
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| 156 |
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| 157 | # print the last line of a file (emulates "tail -1")
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| 158 | sed '$!d' # method 1
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| 159 | sed -n '$p' # method 2
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| 160 |
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| 161 | # print only lines which match regular expression (emulates "grep")
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| 162 | sed -n '/regexp/p' # method 1
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| 163 | sed '/regexp/!d' # method 2
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| 164 |
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| 165 | # print only lines which do NOT match regexp (emulates "grep -v")
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| 166 | sed -n '/regexp/!p' # method 1, corresponds to above
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| 167 | sed '/regexp/d' # method 2, simpler syntax
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| 168 |
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| 169 | # print the line immediately before a regexp, but not the line
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| 170 | # containing the regexp
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| 171 | sed -n '/regexp/{g;1!p;};h'
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| 172 |
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| 173 | # print the line immediately after a regexp, but not the line
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| 174 | # containing the regexp
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| 175 | sed -n '/regexp/{n;p;}'
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| 176 |
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| 177 | # print 1 line of context before and after regexp, with line number
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| 178 | # indicating where the regexp occurred (similar to "grep -A1 -B1")
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| 179 | sed -n -e '/regexp/{=;x;1!p;g;$!N;p;D;}' -e h
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| 180 |
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| 181 | # grep for AAA and BBB and CCC (in any order)
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| 182 | sed '/AAA/!d; /BBB/!d; /CCC/!d'
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| 183 |
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| 184 | # grep for AAA and BBB and CCC (in that order)
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| 185 | sed '/AAA.*BBB.*CCC/!d'
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| 186 |
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| 187 | # grep for AAA or BBB or CCC (emulates "egrep")
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| 188 | sed -e '/AAA/b' -e '/BBB/b' -e '/CCC/b' -e d # most seds
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| 189 | gsed '/AAA\|BBB\|CCC/!d' # GNU sed only
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| 190 |
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| 191 | # print paragraph if it contains AAA (blank lines separate paragraphs)
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| 192 | # HHsed v1.5 must insert a 'G;' after 'x;' in the next 3 scripts below
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| 193 | sed -e '/./{H;$!d;}' -e 'x;/AAA/!d;'
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| 194 |
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| 195 | # print paragraph if it contains AAA and BBB and CCC (in any order)
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| 196 | sed -e '/./{H;$!d;}' -e 'x;/AAA/!d;/BBB/!d;/CCC/!d'
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| 197 |
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| 198 | # print paragraph if it contains AAA or BBB or CCC
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| 199 | sed -e '/./{H;$!d;}' -e 'x;/AAA/b' -e '/BBB/b' -e '/CCC/b' -e d
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| 200 | gsed '/./{H;$!d;};x;/AAA\|BBB\|CCC/b;d' # GNU sed only
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| 201 |
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| 202 | # print only lines of 65 characters or longer
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| 203 | sed -n '/^.\{65\}/p'
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| 204 |
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| 205 | # print only lines of less than 65 characters
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| 206 | sed -n '/^.\{65\}/!p' # method 1, corresponds to above
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| 207 | sed '/^.\{65\}/d' # method 2, simpler syntax
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| 208 |
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| 209 | # print section of file from regular expression to end of file
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| 210 | sed -n '/regexp/,$p'
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| 211 |
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| 212 | # print section of file based on line numbers (lines 8-12, inclusive)
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| 213 | sed -n '8,12p' # method 1
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| 214 | sed '8,12!d' # method 2
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| 215 |
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| 216 | # print line number 52
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| 217 | sed -n '52p' # method 1
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| 218 | sed '52!d' # method 2
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| 219 | sed '52q;d' # method 3, efficient on large files
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| 220 |
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| 221 | # beginning at line 3, print every 7th line
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| 222 | gsed -n '3~7p' # GNU sed only
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| 223 | sed -n '3,${p;n;n;n;n;n;n;}' # other seds
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| 224 |
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| 225 | # print section of file between two regular expressions (inclusive)
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| 226 | sed -n '/Iowa/,/Montana/p' # case sensitive
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| 227 |
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| 228 | SELECTIVE DELETION OF CERTAIN LINES:
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| 229 |
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| 230 | # print all of file EXCEPT section between 2 regular expressions
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| 231 | sed '/Iowa/,/Montana/d'
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| 232 |
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| 233 | # delete duplicate, consecutive lines from a file (emulates "uniq").
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| 234 | # First line in a set of duplicate lines is kept, rest are deleted.
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| 235 | sed '$!N; /^\(.*\)\n\1$/!P; D'
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| 236 |
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| 237 | # delete duplicate, nonconsecutive lines from a file. Beware not to
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| 238 | # overflow the buffer size of the hold space, or else use GNU sed.
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| 239 | sed -n 'G; s/\n/&&/; /^\([ -~]*\n\).*\n\1/d; s/\n//; h; P'
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| 240 |
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| 241 | # delete all lines except duplicate lines (emulates "uniq -d").
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| 242 | sed '$!N; s/^\(.*\)\n\1$/\1/; t; D'
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| 243 |
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| 244 | # delete the first 10 lines of a file
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| 245 | sed '1,10d'
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| 246 |
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| 247 | # delete the last line of a file
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| 248 | sed '$d'
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| 249 |
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| 250 | # delete the last 2 lines of a file
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| 251 | sed 'N;$!P;$!D;$d'
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| 252 |
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| 253 | # delete the last 10 lines of a file
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| 254 | sed -e :a -e '$d;N;2,10ba' -e 'P;D' # method 1
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| 255 | sed -n -e :a -e '1,10!{P;N;D;};N;ba' # method 2
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| 256 |
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| 257 | # delete every 8th line
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| 258 | gsed '0~8d' # GNU sed only
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| 259 | sed 'n;n;n;n;n;n;n;d;' # other seds
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| 260 |
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| 261 | # delete ALL blank lines from a file (same as "grep '.' ")
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| 262 | sed '/^$/d' # method 1
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| 263 | sed '/./!d' # method 2
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| 264 |
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| 265 | # delete all CONSECUTIVE blank lines from file except the first; also
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| 266 | # deletes all blank lines from top and end of file (emulates "cat -s")
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| 267 | sed '/./,/^$/!d' # method 1, allows 0 blanks at top, 1 at EOF
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| 268 | sed '/^$/N;/\n$/D' # method 2, allows 1 blank at top, 0 at EOF
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| 269 |
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| 270 | # delete all CONSECUTIVE blank lines from file except the first 2:
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| 271 | sed '/^$/N;/\n$/N;//D'
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| 272 |
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| 273 | # delete all leading blank lines at top of file
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| 274 | sed '/./,$!d'
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| 275 |
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| 276 | # delete all trailing blank lines at end of file
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| 277 | sed -e :a -e '/^\n*$/{$d;N;ba' -e '}' # works on all seds
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| 278 | sed -e :a -e '/^\n*$/N;/\n$/ba' # ditto, except for gsed 3.02*
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| 279 |
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| 280 | # delete the last line of each paragraph
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| 281 | sed -n '/^$/{p;h;};/./{x;/./p;}'
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| 282 |
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| 283 | SPECIAL APPLICATIONS:
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| 284 |
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| 285 | # remove nroff overstrikes (char, backspace) from man pages. The 'echo'
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| 286 | # command may need an -e switch if you use Unix System V or bash shell.
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| 287 | sed "s/.`echo \\\b`//g" # double quotes required for Unix environment
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| 288 | sed 's/.^H//g' # in bash/tcsh, press Ctrl-V and then Ctrl-H
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| 289 | sed 's/.\x08//g' # hex expression for sed v1.5
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| 290 |
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| 291 | # get Usenet/e-mail message header
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| 292 | sed '/^$/q' # deletes everything after first blank line
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| 293 |
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| 294 | # get Usenet/e-mail message body
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| 295 | sed '1,/^$/d' # deletes everything up to first blank line
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| 296 |
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| 297 | # get Subject header, but remove initial "Subject: " portion
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| 298 | sed '/^Subject: */!d; s///;q'
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| 299 |
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| 300 | # get return address header
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| 301 | sed '/^Reply-To:/q; /^From:/h; /./d;g;q'
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| 302 |
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| 303 | # parse out the address proper. Pulls out the e-mail address by itself
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| 304 | # from the 1-line return address header (see preceding script)
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| 305 | sed 's/ *(.*)//; s/>.*//; s/.*[:<] *//'
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| 306 |
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| 307 | # add a leading angle bracket and space to each line (quote a message)
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| 308 | sed 's/^/> /'
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| 309 |
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| 310 | # delete leading angle bracket & space from each line (unquote a message)
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| 311 | sed 's/^> //'
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| 312 |
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| 313 | # remove most HTML tags (accommodates multiple-line tags)
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| 314 | sed -e :a -e 's/<[^>]*>//g;/</N;//ba'
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| 315 |
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| 316 | # extract multi-part uuencoded binaries, removing extraneous header
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| 317 | # info, so that only the uuencoded portion remains. Files passed to
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| 318 | # sed must be passed in the proper order. Version 1 can be entered
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| 319 | # from the command line; version 2 can be made into an executable
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| 320 | # Unix shell script. (Modified from a script by Rahul Dhesi.)
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| 321 | sed '/^end/,/^begin/d' file1 file2 ... fileX | uudecode # vers. 1
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| 322 | sed '/^end/,/^begin/d' "$@" | uudecode # vers. 2
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| 323 |
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| 324 | # zip up each .TXT file individually, deleting the source file and
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| 325 | # setting the name of each .ZIP file to the basename of the .TXT file
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| 326 | # (under DOS: the "dir /b" switch returns bare filenames in all caps).
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| 327 | echo @echo off >zipup.bat
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| 328 | dir /b *.txt | sed "s/^\(.*\)\.TXT/pkzip -mo \1 \1.TXT/" >>zipup.bat
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| 329 |
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| 330 | TYPICAL USE: Sed takes one or more editing commands and applies all of
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| 331 | them, in sequence, to each line of input. After all the commands have
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| 332 | been applied to the first input line, that line is output and a second
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| 333 | input line is taken for processing, and the cycle repeats. The
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| 334 | preceding examples assume that input comes from the standard input
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| 335 | device (i.e, the console, normally this will be piped input). One or
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| 336 | more filenames can be appended to the command line if the input does
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| 337 | not come from stdin. Output is sent to stdout (the screen). Thus:
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| 338 |
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| 339 | cat filename | sed '10q' # uses piped input
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| 340 | sed '10q' filename # same effect, avoids a useless "cat"
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| 341 | sed '10q' filename > newfile # redirects output to disk
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| 342 |
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| 343 | For additional syntax instructions, including the way to apply editing
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| 344 | commands from a disk file instead of the command line, consult "sed &
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| 345 | awk, 2nd Edition," by Dale Dougherty and Arnold Robbins (O'Reilly,
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| 346 | 1997; http://www.ora.com), "UNIX Text Processing," by Dale Dougherty
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| 347 | and Tim O'Reilly (Hayden Books, 1987) or the tutorials by Mike Arst
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| 348 | distributed in U-SEDIT2.ZIP (many sites). To fully exploit the power
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| 349 | of sed, one must understand "regular expressions." For this, see
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| 350 | "Mastering Regular Expressions" by Jeffrey Friedl (O'Reilly, 1997).
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| 351 | The manual ("man") pages on Unix systems may be helpful (try "man
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| 352 | sed", "man regexp", or the subsection on regular expressions in "man
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| 353 | ed"), but man pages are notoriously difficult. They are not written to
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| 354 | teach sed use or regexps to first-time users, but as a reference text
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| 355 | for those already acquainted with these tools.
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| 356 |
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| 357 | QUOTING SYNTAX: The preceding examples use single quotes ('...')
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| 358 | instead of double quotes ("...") to enclose editing commands, since
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| 359 | sed is typically used on a Unix platform. Single quotes prevent the
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| 360 | Unix shell from intrepreting the dollar sign ($) and backquotes
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| 361 | (`...`), which are expanded by the shell if they are enclosed in
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| 362 | double quotes. Users of the "csh" shell and derivatives will also need
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| 363 | to quote the exclamation mark (!) with the backslash (i.e., \!) to
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| 364 | properly run the examples listed above, even within single quotes.
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| 365 | Versions of sed written for DOS invariably require double quotes
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| 366 | ("...") instead of single quotes to enclose editing commands.
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| 367 |
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| 368 | USE OF '\t' IN SED SCRIPTS: For clarity in documentation, we have used
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| 369 | the expression '\t' to indicate a tab character (0x09) in the scripts.
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| 370 | However, most versions of sed do not recognize the '\t' abbreviation,
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| 371 | so when typing these scripts from the command line, you should press
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| 372 | the TAB key instead. '\t' is supported as a regular expression
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| 373 | metacharacter in awk, perl, and HHsed, sedmod, and GNU sed v3.02.80.
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| 374 |
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| 375 | VERSIONS OF SED: Versions of sed do differ, and some slight syntax
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| 376 | variation is to be expected. In particular, most do not support the
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| 377 | use of labels (:name) or branch instructions (b,t) within editing
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| 378 | commands, except at the end of those commands. We have used the syntax
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| 379 | which will be portable to most users of sed, even though the popular
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| 380 | GNU versions of sed allow a more succinct syntax. When the reader sees
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| 381 | a fairly long command such as this:
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| 382 |
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| 383 | sed -e '/AAA/b' -e '/BBB/b' -e '/CCC/b' -e d
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| 384 |
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| 385 | it is heartening to know that GNU sed will let you reduce it to:
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| 386 |
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| 387 | sed '/AAA/b;/BBB/b;/CCC/b;d' # or even
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| 388 | sed '/AAA\|BBB\|CCC/b;d'
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| 389 |
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| 390 | In addition, remember that while many versions of sed accept a command
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| 391 | like "/one/ s/RE1/RE2/", some do NOT allow "/one/! s/RE1/RE2/", which
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| 392 | contains space before the 's'. Omit the space when typing the command.
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| 393 |
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| 394 | OPTIMIZING FOR SPEED: If execution speed needs to be increased (due to
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| 395 | large input files or slow processors or hard disks), substitution will
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| 396 | be executed more quickly if the "find" expression is specified before
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| 397 | giving the "s/.../.../" instruction. Thus:
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| 398 |
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| 399 | sed 's/foo/bar/g' filename # standard replace command
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| 400 | sed '/foo/ s/foo/bar/g' filename # executes more quickly
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| 401 | sed '/foo/ s//bar/g' filename # shorthand sed syntax
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| 402 |
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| 403 | On line selection or deletion in which you only need to output lines
|
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| 404 | from the first part of the file, a "quit" command (q) in the script
|
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| 405 | will drastically reduce processing time for large files. Thus:
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| 406 |
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| 407 | sed -n '45,50p' filename # print line nos. 45-50 of a file
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| 408 | sed -n '51q;45,50p' filename # same, but executes much faster
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| 409 |
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| 410 | If you have any additional scripts to contribute or if you find errors
|
|---|
| 411 | in this document, please send e-mail to the compiler. Indicate the
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| 412 | version of sed you used, the operating system it was compiled for, and
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| 413 | the nature of the problem. Various scripts in this file were written
|
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| 414 | or contributed by:
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| 415 |
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| 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"
|
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| 421 | Eric Pement <pemente@northpark.edu> # author of this document
|
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| 422 | Ken Pizzini <ken@halcyon.com> # author of GNU sed v3.02
|
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| 423 | S.G. Ravenhall <stew.ravenhall@totalise.co.uk> # great de-html script
|
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| 424 | Greg Ubben <gsu@romulus.ncsc.mil> # many contributions & much help
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| 425 | -------------------------------------------------------------------------
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