Commands using od (28)

  • Add Rudimentary Logging Levels According to STDOUT/STDERR

    This is a bit of a bash hack to catch STDERR and append a log level to it. So for example, if your script has pseudo loglevels like so: echo "INFO - finding files" [ -f ${files} ] || echo "WARN - no files found" Any subcommands that write to STDERR will screw that up Adding 2> >(fb=$(dd bs=1 count=1 2>/dev/null | od -t o1 -A n); [ "$fb" ] && err=$(printf "\\${fb# }"; cat) && echo "ERROR - $err") to the command does the following: 2> Redirect STDERR >( Spawn a subshell (STDERR is then redirected to the file descriptor for this subshell) fb=$(....) get the first byte of input [ "$fb" ] test if there's a first byte && err=$(printf....) save the output to the $err variable && echo "ERROR - $err" append your pseudo loglevel and the error message Heavily borrowed from https://unix.stackexchange.com/questions/33049/check-if-pipe-is-empty-and-run-a-command-on-the-data-if-it-isnt Show Sample Output


    0
    [command] 2> >(fb=$(dd bs=1 count=1 2>/dev/null | od -t o1 -A n); [ "$fb" ] && err=$(printf "\\${fb# }"; cat) && echo "ERROR - $err")
    tyzbit · 2017-10-16 22:22:42 22
  • Random unsigned integer

    Grab 4 bytes from www.random.org over ssl and format them as an integer


    -1
    curl -s "https://www.random.org/cgi-bin/randbyte?nbytes=4" | od -DAn
    PhillipNordwall · 2010-11-09 18:26:24 5
  • Generat a Random MAC address


    -1
    2>/dev/null dd if=/dev/urandom bs=1 count=6 | od -t x1 |sed '2d;s/^0\+ //;s/ /:/g'
    flyc0r · 2011-05-17 21:04:35 4
  •  < 1 2

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list files recursively by size

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