Commands by varenc (2)

  • Realtime lines per second in a log file, with history

    This is similar to standard `pv`, but it retains the rate history instead of only showing the current rate. This is useful for spotting changes. To do this, -f is used to force pv to output, and stderr is redirected to stdout so that `tr` can swap the carriage returns for new lines. (doesn't work correctly is in zsh for some reason. Tail's output isn't redirected to /dev/null like it is in bash. anyone know why? ???????) Show Sample Output


    1
    tail -f access.log | pv -l -i10 -r -f 2>&1 >/dev/null | tr /\\r \ \\n
    varenc · 2020-04-19 02:07:40 11
  • Random number with a normal distribution between 1 and X

    Print a random number between 1 and 50 with a normal distribution around the center. The numbers around the middle are the most likely to occur and the farther you get from that the less and less common they are. You can test this and observe the number distribution with this command: for i in `seq 100000`; do echo $[(${RANDOM}%40+${RANDOM}%40)/2+1]; done | sort -n | uniq -c Show Sample Output


    0
    echo $[(${RANDOM}%100+${RANDOM}%100)/2+1]
    varenc · 2019-05-16 00:58:25 0

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