shell - how to grep the last occurrence of the line pattern -


i have file contents,

x x b x c

i want grep last occurrence,

x c

when try

sed -n  "/x/,/b/p" file

it lists lines. beginning x c

i'm not sure if got question right, here answers:

  • print last occurence of x:

    grep x file | tail -1

  • print input lines beginning first matching line:

    awk "/x/ { flag = 1 }; flag" txt

  • print lines beginning last matching line (prints lines if no match found):

    tac file | awk "!flag; /x/ { flag = 1 }; " | tac

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