Commands by ktoso (3)

  • Yeah I know it's been up here a million times, but this service is a really clean and nice one. Nothing but your IP address on it. Actually I was to write something like this, and noticed this on appspot... ;) Show Sample Output


    25
    curl ip.appspot.com
    ktoso · 2009-10-31 21:11:10 8
  • After executing this, click on a window you want to track X Window events in. Explaination: "xev will track events in the window with the following -id, which we get by greping window information obtained by xwininfo" Show Sample Output


    2
    xev -id `xwininfo | grep 'Window id' | awk '{print $4}'`
    ktoso · 2009-09-19 22:47:16 4
  • Can be used to discover what programms create internet traffic. Skip the part after awk to get more details. Has anyone an idea why the uniq doesn't work propperly here (see sample output)? Show Sample Output


    -1
    netstat -lantp | grep -i establ | awk -F/ '{print $2}' | uniq | sort
    ktoso · 2009-09-19 13:54:36 5

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Pick a random line from a file

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concatenate compressed and uncompressed logs
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Create a mirror of a local folder, on a remote server
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Limit memory usage per script/program
When I'm testing some scripts or programs, they end up using more memory than anticipated. In that case, computer nearly halts due to swap space usage, and sometimes I have to press Magic SysRq+REISUB to reboot. So, I was looking for a way to limit memory usage per script and found out that ulimit can limit memory. If you run it this way: $ $ ulimit -v 1000000 . $ $ scriptname Then the new memory limit will be valid for that shell. I think changing the limit within a subshell is much more flexible and it won't interfere with your current shell ulimit settings. note: -v 1000000 corresponds to approximately 1GB of RAM

Perl One Liner to Generate a Random IP Address
A bash version.


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