Shell script to tail a file with unknown numbers

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09-13-2019

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Just for the fun of it - how far would this get you:

Code:

FL=$(wc -l < inputfile)
while read
  do    case $REPLY in
        [tT]*)  CMD="NR>$((FL - ${REPLY:1}))";;
        [pP]*)  CMD="/${REPLY:1}/";;
        [fF]*)  CMD=1;;
            *)  echo "usage: CMD Param; CMD ~ t)ail, p)attern search, f)ull"
                continue
        esac

        ((++CNT))
        awk "$CMD" inputfile > /tmp/log.$CNT
  done

Last edited by RudiC; 09-13-2019 at 08:37 AM..

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