Commands by 5z474n (3)

  • Add temporary entry to authorized_keys

    If you frequently need to connect to your ubersecure mainframe from various uberunsafe machines, you have to face difficult decision: (a) type the password everytime during the session (lame), (b) add local public key to mainframes authorized_keys file (unsafe), (c) as above, but remove this key at the end of the session (pain in the a55). So let's say you save The Command to tempauth file in bin directory of your mainframe's account and make it executable. Then, while you're on one of these unsafe ones, do: cat $HOME/.ssh/id_rsa.pub|ssh 5z474n@mainframe.nl bin/tempauth 30 and password prompts stop the harassment for 30 minutes and you don't have to care to remove the unsafe key after that.


    1
    Keys=$HOME/.ssh/authorized_keys;Back=$Keys.tmp.bak;Time=${1:-15};cp $Keys $Back;cat /dev/stdin >>$Keys;echo mv $Back $Keys|at now+${Time}minutes;
    5z474n · 2009-07-15 23:45:02 8
  • Hear the mice moving

    Beeps on mouse's every move. Bear in mind that, at least on Ubuntu, /dev/input/mice can be read only by root.


    4
    while true; do beep -l66 -f`head -c2 /dev/input/mice|hexdump -d|awk 'NR==1{print $2%10000}'`; done
    5z474n · 2009-07-11 12:01:27 22
  • Beep siren

    Infinitely plays beeps with sinusoidally changing sound frequency. Ideal for alarm on an event.


    1
    tempo=33; slope=10; maxfreq=888; function sinus { echo "s($1/$slope)*$maxfreq"|bc -l|tr -d '-'; }; for((i=1;;i++)); do beep -l$tempo -f`sinus $i`; done
    5z474n · 2009-07-10 21:24:11 3

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