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Bookmarks on Finite Element Analisys

http://www.engineersedge.com/engineering/Engineering_Downloads/Finite_Element_Software_Public_Domain/
http://geuz.org/gmsh/
http://www.range-software.com/
http://www.caelinux.com/

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uSleep on windows (win32)

I am facing a terrible issue regarding timing on windows.

Googling arround, I've found those infos:
Using QueryPerformanceCounter and QueryPerformanceFrequency APIs in Dev-C++
(http://yeohhs.blogspot.com/2005/08/using-queryperformancecounter-and_13.html)
QueryPerformanceCounter() vs. GetTickCount()
http://www.delphifaq.com/faq/delphi_windows_API/f345.shtml
How to time a block of code
http://www.cryer.co.uk/brian/delphi/howto_time_code.htm
And Results of some quick research on timing in Win32 http://www.geisswerks.com/ryan/FAQS/timing.html
With that I'm trying to write something like a uSleep function for windows:


#include<windows.h>

voiduSleep(int waitTime){
__int64 time1 = 0, time2 = 0, sysFreq = 0;

QueryPerformanceCounter((LARGE_INTEGER *)&time1);
QueryPerformanceFrequency((LARGE_INTEGER *)&freq);
do{
QueryPerformanceCounter((LARGE_INTEGER *)&time2);

// }while((((time2-time1)*1.0)/sysFreq)<waitTime);
}while( (time2-time1) <waitTime);
}

There is also already a nanosleep…

More trickery with gnuplot dumb terminal

In my post "Plotting memory usage on console" the chart doesn't pan the data.
Now, using a named pipe, the effect got a little bit nicer.
First, we have to run the memUsage.sh script to get a file filled with memory usage info:
./memUsage.sh > memUsage.dat &
Then we have to create a named pipe:
mkfifo pipe
Now we have to run another process to tail only the last 64 lines from the memUsage.dat
while [ 1 ]; do tail -64 memUsage.dat> pipe; done &
And now we just have to plot the data from the pipe:
watch -n 1 'gnuplot -e "set terminal dumb;p \"pipe\" with lines"'
And that is it!

Checking auth.log for ssh brute force attacks

As I am letting my personal computer always on, as a homelinux server, I decided to check if someone is trying to breaking in with SSH brute force attacks.

First I did a grep for fail at the /var/log/auth.log. (grep -i /var/log/auth.log)

And I got lots of lines with the string "fail". With [grep -i /var/log/auth.log | wc -l] I figured out that were 1164 fail entries at auth.log

With an [grep -i fail auth.log | cut -d " " -f 6 | sort | uniq] I checked that were two kind of failed attempts:
Failed
pam_unix(sshd:auth):

So I wrote the following line to check with which users they were attempting to log:
grep Failed auth.log | cut -d " " -f 11 | sort | uniq | while read line ; do echo -n $line" "; grep $line auth.log | wc -l; done | sort -n -k 2

Here, the field position (the number 11 at the above command lines [-f 11]) may change in some systems. At my desktop at work, the username came at the position 9.

Here are the "top ten":
root 2922
user 2884