451.html

著名的linux英雄站点的文档打包

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 # Cannot be done with DOS versions of sed. Use "tr" instead.
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 tr -d 
 &lt;infile &gt;outfile            # GNU tr version 1.22 or higher
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 # delete leading whitespace (spaces, tabs) from front of each line
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 # aligns all text flush left
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 sed 's/^[ 	]*//'                    # see note on '	' at end of file
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 # delete trailing whitespace (spaces, tabs) from end of each line
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 sed 's/[ 	]*$//'                    # see note on '	' at end of file
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 # delete BOTH leading and trailing whitespace from each line
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 sed 's/^[ 	]*//;s/[ 	]*$//'
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 # insert 5 blank spaces at beginning of each line (make page offset)
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 sed 's/^/     /'
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 # align all text flush right on a 79-column width
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 sed -e :a -e 's/^.{1,78}$/ &/;ta'  # set at 78 plus 1 space
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 # center all text in the middle of 79-column width. In method 1,
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 # spaces at the beginning of the line are significant, and trailing
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 # spaces are appended at the end of the line. In method 2, spaces at
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 # the beginning of the line are discarded in centering the line, and
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 # no trailing spaces appear at the end of lines.
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 sed  -e :a -e 's/^.{1,77}$/ & /;ta'                     # method 1
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 sed  -e :a -e 's/^.{1,77}$/ &/;ta' -e 's/( *)1/1/'  # method 2
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 # substitute (find and replace) "foo" with "bar" on each line
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 sed 's/foo/bar/'             # replaces only 1st instance in a line
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 sed 's/foo/bar/4'            # replaces only 4th instance in a line
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 sed 's/foo/bar/g'            # replaces ALL instances in a line
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 sed 's/(.*)foo(.*foo)/1bar2/' # replace the next-to-last case
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 sed 's/(.*)foo/1bar/'            # replace only the last case
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 # substitute "foo" with "bar" ONLY for lines which contain "baz"
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 sed '/baz/s/foo/bar/g'
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 # substitute "foo" with "bar" EXCEPT for lines which contain "baz"
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 sed '/baz/!s/foo/bar/g'
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 # change "scarlet" or "ruby" or "puce" to "red"
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 sed 's/scarlet/red/g;s/ruby/red/g;s/puce/red/g'   # most seds
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 gsed 's/scarlet|ruby|puce/red/g'                # GNU sed only
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 # reverse order of lines (emulates "tac")
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 # bug/feature in HHsed v1.5 causes blank lines to be deleted
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 sed '1!G;h;$!d'               # method 1
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 sed -n '1!G;h;$p'             # method 2
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 # reverse each character on the line (emulates "rev")
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 sed '/
/!G;s/(.)(.*
)/&21/;//D;s/.//'
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 # join pairs of lines side-by-side (like "paste")
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 sed '$!N;s/
/ /'
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 # if a line ends with a backslash, append the next line to it
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 sed -e :a -e '/$/N; s/
//; ta'
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 # if a line begins with an equal sign, append it to the previous line
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 # and replace the "=" with a single space
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 sed -e :a -e '$!N;s/
=/ /;ta' -e 'P;D'
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 # add commas to numeric strings, changing "1234567" to "1,234,567"
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 gsed ':a;s/B[0-9]{3}&gt;/,&/;ta'                     # GNU sed
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 sed -e :a -e 's/(.*[0-9])([0-9]{3})/1,2/;ta'  # other seds
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 # add commas to numbers with decimal points and minus signs (GNU sed)
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 gsed ':a;s/(^|[^0-9.])([0-9]+)([0-9]{3})/12,3/g;ta'
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 # add a blank line every 5 lines (after lines 5, 10, 15, 20, etc.)
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 gsed '0~5G'                  # GNU sed only
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 sed 'n;n;n;n;G;'             # other seds
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SELECTIVE PRINTING OF CERTAIN LINES:
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 # print first 10 lines of file (emulates behavior of "head")
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 sed 10q
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 # print first line of file (emulates "head -1")
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 sed q
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 # print the last 10 lines of a file (emulates "tail")
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 sed -e :a -e '$q;N;11,$D;ba'
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 # print the last 2 lines of a file (emulates "tail -2")
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 sed '$!N;$!D'
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 # print the last line of a file (emulates "tail -1")
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 sed '$!d'                    # method 1
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 sed -n '$p'                  # method 2
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 # print only lines which match regular expression (emulates "grep")
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 sed -n '/regexp/p'           # method 1
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 sed '/regexp/!d'             # method 2
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 # print only lines which do NOT match regexp (emulates "grep -v")
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 sed -n '/regexp/!p'          # method 1, corresponds to above
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 sed '/regexp/d'              # method 2, simpler syntax
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 # print the line immediately before a regexp, but not the line
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 # containing the regexp
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 sed -n '/regexp/{g;1!p;};h'
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 # print the line immediately after a regexp, but not the line
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 # containing the regexp
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 sed -n '/regexp/{n;p;}'
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 # print 1 line of context before and after regexp, with line number
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 # indicating where the regexp occurred (similar to "grep -A1 -B1")
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 sed -n -e '/regexp/{=;x;1!p;g;$!N;p;D;}' -e h
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 # grep for AAA and BBB and CCC (in any order)
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 sed '/AAA/!d; /BBB/!d; /CCC/!d'
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 # grep for AAA and BBB and CCC (in that order)
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 sed '/AAA.*BBB.*CCC/!d'
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 # grep for AAA or BBB or CCC (emulates "egrep")
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 sed -e '/AAA/b' -e '/BBB/b' -e '/CCC/b' -e d    # most seds
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 gsed '/AAA|BBB|CCC/!d'                        # GNU sed only
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 # print paragraph if it contains AAA (blank lines separate paragraphs)
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 # HHsed v1.5 must insert a 'G;' after 'x;' in the next 3 scripts below
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 sed -e '/./{H;$!d;}' -e 'x;/AAA/!d;'
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 # print paragraph if it contains AAA and BBB and CCC (in any order)
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 sed -e '/./{H;$!d;}' -e 'x;/AAA/!d;/BBB/!d;/CCC/!d'
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 # print paragraph if it contains AAA or BBB or CCC
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 sed -e '/./{H;$!d;}' -e 'x;/AAA/b' -e '/BBB/b' -e '/CCC/b' -e d
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 gsed '/./{H;$!d;};x;/AAA|BBB|CCC/b;d'         # GNU sed only
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 # print only lines of 65 characters or longer
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 sed -n '/^.{65}/p'
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 # print only lines of less than 65 characters
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 sed -n '/^.{65}/!p'        # method 1, corresponds to above
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 sed '/^.{65}/d'            # method 2, simpler syntax
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 # print section of file from regular expression to end of file
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 sed -n '/regexp/,$p'
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 # print section of file based on line numbers (lines 8-12, inclusive)
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 sed -n '8,12p'               # method 1
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 sed '8,12!d'                 # method 2
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 # print line number 52
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 sed -n '52p'                 # method 1
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 sed '52!d'                   # method 2
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 sed '52q;d'                  # method 3, efficient on large files
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 # beginning at line 3, print every 7th line
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 gsed -n '3~7p'               # GNU sed only
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 sed -n '3,${p;n;n;n;n;n;n;}' # other seds
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 # print section of file between two regular expressions (inclusive)
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 sed -n '/Iowa/,/Montana/p'             # case sensitive
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SELECTIVE DELETION OF CERTAIN LINES:
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 # print all of file EXCEPT section between 2 regular expressions
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 sed '/Iowa/,/Montana/d'
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 # delete duplicate, consecutive lines from a file (emulates "uniq").
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 # First line in a set of duplicate lines is kept, rest are deleted.
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 sed '$!N; /^(.*)
1$/!P; D'
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 # delete duplicate, nonconsecutive lines from a file. Beware not to
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 # overflow the buffer size of the hold space, or else use GNU sed.
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 sed -n 'G; s/
/&&/; /^([ -~]*
).*
1/d; s/
//; h; P'
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 # delete the first 10 lines of a file
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 sed '1,10d'
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 # delete the last line of a file
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 sed '$d'
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 # delete the last 2 lines of a file
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 sed 'N;$!P;$!D;$d'
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 # delete the last 10 lines of a file
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 sed -e :a -e '$d;N;2,10ba' -e 'P;D'   # method 1
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 sed -n -e :a -e '1,10!{P;N;D;};N;ba'  # method 2
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 # delete every 8th line
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 gsed '0~8d'                           # GNU sed only
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 sed 'n;n;n;n;n;n;n;d;'                # other seds
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 # delete ALL blank lines from a file (same as "grep '.' ")
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 sed '/^$/d'                           # method 1
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 sed '/./!d'                           # method 2
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