Commands by kostis (3)

  • Converts all pngs in a folder to webp using all available cores

    As an alternative to the above command, this one ditches the unnecessary and complicated for loop in favor of a way faster multi-core approach for a task that's more CPU than I/O intensive, making it a perfect suite for GNU parallel


    4
    parallel cwebp -q 80 {} -o {.}.webp ::: *.png
    kostis · 2018-12-07 23:37:24 1
  • quick integer CPU benchmark

    You could have that little benchmark run on all cores in parallel, as a multi-core benchmark or stress test First find the number of cores, then have parallel iterate over that in, well, parallel Show Sample Output


    -1
    time cat /proc/cpuinfo |grep proc|wc -l|xargs seq|parallel -N 0 echo "2^2^20" '|' bc
    kostis · 2018-12-06 05:36:55 0
  • small CPU benchmark with PI, bc and time.

    Broken in two parts, first get the number of cores with cat /proc/cpuinfo |grep proc|wc -l and create a integer sequence with that number (xargs seq), then have GNU parallel loop that many times over the given command. Cheers! Show Sample Output


    -2
    time cat /proc/cpuinfo |grep proc|wc -l|xargs seq|parallel -N 0 echo "scale=4000\; a\(1\)\*4" '|' bc -l
    kostis · 2018-12-06 05:15:24 2

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cycle through a 256 colour palette
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Replace all backward slashes with forward slashes
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Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Kill most recently created process.
Kills the most recently created firefox process.

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Returns true (0) if the string is into $var, or false (1) if not.

sort ugly text
Often, when sorting you want the sort to ignore extraneous characters. The b, d, and f tell sort to ignore leading blanks, use 'dictionary order' (ignore punctuation), and ignore (fold) case. Add a "u" if you only want one copy of duplicate lines. This is a great command to use within vim to sort lines of text, using !}sort -bdf

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

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