[ORIGINAL CREATION] tact and skill of sed

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sed '/cryincold/ p' text                   // Print lines match "cryincold"
sed '/cryincold/! p' text                  // Print lines do NOT match "cryincold", pay attention to theexclamatory mark !

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An & which is a special character in sed & awk is replaced by the matched substring. /& put literal &.

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sed 110q filename    // print filename the first 110 lines
sed -n '10, 20p' filename      // print lines between 10 and 20

 

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sed /^[[:space:]]*$/d  file_name  // Erase all space line.

 

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sed -n 's/.*/[/(.*/)/].*//1/p' filename                   // get all section names between [ and ]