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 3
  • 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 7
  • 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 5
  • 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 8
  • Watch Network Service Activity in Real-time


    100
    lsof -i
    hank · 2009-04-25 14:24:04 15
  • 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 7
  • 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 4

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sync two folders except hidden files

Display a block of text: multi-line grep with perl
-n reads input, line by line, in a loop sending to $_ Equivalent to while () { mycode } -e execute the following quoted string (i.e. do the following on the same line as the perl command) the elipses .. operator behaves like a range, remembering the state from line to line.

interactive rss-based colorful commandline-fu reader perl oneliner (v0.1)
required packages: curl, xml2, html2text command is truncated, see 'sample output'

How to copy CD/DVD into hard disk (.iso)
A dear friend of mine asked me how do I copy a DVD to your hard drive? If you want to make a copy of the ISO image that was burned to a CD or DVD, insert that medium into your CD/DVD drive and (assuming /dev/cdrom is associated with your computer?s CD drive) type the following command

Mount important virtual system directories under chroot'ed directory
The command is useful when, e.g., booting an existing system with a rescue or installation CD where you need to chroot into the hard-disk and be able to do stuff which accesses kernel info (e.g. when installing Ubuntu desktop with LVM2 you need to mount and chroot the hard disk from a shell window in order to install packages and run initramfs inside chroot). The command assumes that /mnt/xxx is where the chroot'ed environment's root file system on the hard disk is mounted.

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

Scan your LAN for unauthorized IPs
populate the auth.hosts file with a list of IP addresses that are authorized to be in use and when you run this command it will return the addresses that are pingable and not in the authorized list. Can be combined with the "Command line Twitter" command to tweet unauthorized access.

Restart openssh-server on your Synology NAS from commandline.
The correct way to restart openssh-server on your synology nas.

convert .bin / .cue into .iso image
bchunk [-v] [-p] [-r] [-w] [-s]

Simple multi-user encrypted chat server for 5 users
Client ~$ ncat --ssl localhost 9876 Change localhost to the correct ip address.

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