Commands by hank (7)

  • Fetch all GPG keys that are currently missing in your keyring

    The original command doesn't work for me - does something weird with sed (-r) and xargs (-i) with underscores all over... This one works in OSX Lion. I haven't tested it anywhere else, but if you have bash, gpg and perl, it should work. Show Sample Output


    0
    for i in `gpg --list-sigs | perl -ne 'if(/User ID not found/){s/^.+([a-fA-F0-9]{8}).*/\1/; print}' | sort | uniq`; do gpg --keyserver-options no-auto-key-retrieve --recv-keys $i; done
    hank · 2013-03-10 09:15:15 6
  • The 1 millionth fibonacci number

    It's hard to beat C. This is just slightly faster than the bc version on my machine. real 0m26.856s user 0m25.030s sys 0m0.024s Requirements: libgmp headers, gcc. Show Sample Output


    -5
    gcc -x c -o /tmp/out - -lgmp <<< '#include <stdlib.h> ... SEE SAMPLE OUTPUT FOR FULL COMMAND
    hank · 2009-09-10 02:10:46 8
  • Connect to all running screen instances

    There was another line that was dependent on having un-named screen sessions. This just wouldn't do. This one works no matter what the name is. A possible improvement would be removing the perl dependence, but that doesn't effect me.


    2
    for i in `screen -ls | perl -ne'if(/^\s+\d+\.([^\s]+)/){print $1, " "}'`; do gnome-terminal -e "screen -x $i"; done
    hank · 2009-04-25 22:39:24 7
  • Get a summary of network devices in the system

    Basically an improvement on an earlier ethtool command line. Show Sample Output


    0
    for i in /sys/class/net/*; do e=`basename $i`; echo "# $e"; sudo ethtool $e | grep -E "Link|Speed" ; done
    hank · 2009-04-25 14:32:08 10
  • Watch Network Service Activity in Real-time


    102
    lsof -i
    hank · 2009-04-25 14:24:04 26
  • Set Time Zone in Ubuntu

    Reconfigures time zone in Ubuntu, which I cannot figure out how to do through the GUI. Worked like a charm to set my time zone to CEST from EDT.


    3
    sudo dpkg-reconfigure tzdata
    hank · 2009-04-20 02:08:23 9
  • Fix Ubuntu's Broken Sound Server

    Ever since the switch to pulseaudio, Ubuntu users including myself have found themselves with no sound intermittently. To fix this, just use this command and restarts firefox or mplayer or whatever.


    14
    sudo killall -9 pulseaudio; pulseaudio >/dev/null 2>&1 &
    hank · 2009-04-11 20:18:35 8

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openssl Generate Self Signed SSL Certifcate
generating self signed ssl certificate to use in dovecot postfix nginx Self signed certificates can be used for private encryptions between server and client and must be manually accepted on browser/ client

Replace "space" char with "dot" char in current directory file names

split a file by a specific number of lines
Splits the file "my_file" every 500 lines. Will create files called xx01 xx02 and so on. You can change the prefix by using the -f option. Comes in handy for splitting logfiles for example. I am using it for feeding a logfile parser with smaller files instead of one big file (due to performance reasons)

list files recursively by size

Recursive find and replace file extension / suffix (mass rename files)
Find recursively all files in ~/Notes with the extension '.md' and pipe that via xargs to rename command, which will replace every '.md' to '.txt' in this example (existing files will not be overwritten).

Get playlist for Livestream on YouTube

list files recursively by size

delete duplicate lines from a file and keep the order of the other lines
i wanted to delete all duplicate lines from .bash_history and keep the order of the other lines. the command cat's the file and adds line numbers, then sorts by the second column. afterwards uniq omits repeated lines, but skips the first field (the line number). then it sorts by the line numbers and at the end cuts the numbers off.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

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"

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