Physik & Technik

The command ulimit -a shows all limits that are imposed on the current user.

Debian default is 1024 open files per user. This can be increased (only by the super user) by editing the following files:

Uncomment the line
session required pam_limits.so

in the file '/etc/pam.d/su'.

In /etc/security/limits.conf, add the following lines:

username soft nofile 2048
username hard nofile 2048

Change username and 2048 to appropriate values.

The changes will be accepted after a re-login (check ulimit).

If the commands like Ctrl+Q, Ctrl+S or similar do not work in rtorrent, it is possible that flow control is enabled in your terminal/screen-session and you have to disable it!

Press Ctrl+A f in your screen session to disable.
Check the wikipedia article about flow control:
http://en.wikipedia.org/wiki/Software_flow_control

Discussion can be found at:
http://libtorrent.rakshasa.no/ticket/1611

Rtorrent does not accept (self signed) server certificates, where the certificate hostname does not match the site hostname.
The following error will probably be shown:
[SSL peer certificate or SSH remote key was not OK]

rtorrent currently has no option to disable the host checking of certificates, so a small line of code has to be added to the curl_get.cc file (which can be found in /rtorrent/src/core folder)...

After the line
curl_easy_setopt(m_handle, CURLOPT_MAXREDIRS, (long)5);

add the following code
curl_easy_setopt(m_handle, CURLOPT_SSL_VERIFYHOST, (long)0);

Whenever you use boost xml_oarchive, be careful that the closing archive xml tag is written whenever the archive gets destructed!

Therefore, the following won't work:

    std::string dumpXML()
    {
        std::stringstream stringstr_1;
        boost::archive::xml_oarchive xml_output_arch(stringstr);

        AnyClass& custom_data = m_custom;
        xml_output_arch << BOOST_SERIALIZATION_NVP(custom_data);

        return stringstr_1.str();
    }

During testing of the Davical Calender Server i sometimes got a modification
failed error when trying to change Events that have been imported to Davical
via .ics files which originated from Google calender.

I analysed the access logs of the webserver which resulted from the Mozilla Lightning requests and found out that the PUT request
PUT /davical/caldav.php/someting/home/967096cd-c1a6-40e2-930c-04f328cfcc45/test@gmail.com.ics
contained a slash, that was originating from the UID in those specific events.

When using fail2ban with iptables, it is possible that errors occur when fail2ban tries to load the iptable chains...

Error messages are similar to the following:
iptables -I INPUT -p tcp -m multiport --dports smtp -j fail2ban-rulename returned 400

The error codes can have different values like 200, 100, 400.
It seems to be a timing error with iptables.

A fix can be added to the /usr/bin/fail2ban-client python application:

Add the line
time.sleep(0.1)

to the function
def __processCmd(self, cmd, showRet = True):
beautifier = Beautifier() for c in cmd:

Das Deutsche Institut für Wirtschaftsforschung (DIW) sieht derzeit keinen Fachkräftemangel in Deutschland. Dies berichtet das Nachrichtenmagazin "Der Spiegel" in seiner kommenden Ausgabe. Demnach werde das DIW am Dienstag eine Studie zur Entwicklung des Fachkräftebedarfs vorstellen. Der Studie zufolge ließen sich für ein generell knappes Fachkräfteangebot "keine Belege finden". Im Gegenteil bildeten etwa die kaum gestiegenen Löhne ein Indiz dagegen, dass so etwas wie ein Wettbewerb um Fachkräfte bei den Unternehmen eingesetzt habe.

By default, in an inline equation, the indices of a sum are placed besides the sum.
This can be changed by using the \limit command!
$\sum\limits_N$

Babel packet:
Supports multiple languages in a latex document.

\usepackage[ngerman,english]
Uses english as default language and the new german grammar as secondary language.

Use \selectlanguage{language} to switch between languages.

Commands can distinguish between languages using
\iflanguage{ngerman}{Zitiert auf}{cited on}

SumatraPDF supports forward and inverse search when using WinEdt6 or TexnicCenter Latex Editors...

Please note that all paths have to be changed to suit your needs!

Get a modified Sumatra Version here:
http://william.famille-blum.org/software/sumatra/index.html

It allows to specify the inverse search command!
This was the only way, to make inverse search working for me with WinEdt.

Following inverse search commands are used:

WinEdt:
"C:\Software\Office-Bildbearbeitung\Latex\WinEdt6\winedt.exe" "[Open(|%f|);SelPar(%l,8)]"

TexnicCenter

To test:
QuickSystemInfo
RootExpxlorer

I use the following apps:

Öffi from Andreas Schildbach - Very useful app for public transport in Austria, Germany
SlideIt: Keyboard i use - intelligent word recognition with sliding over keys
AK Notepad: For taking notes
Aldiko, FBReader: Ebook reader
APKtor: Software for alternate markets - repository: repo.blackdroid.net
AppBrain Market: Proposals for good apps
AroundMe: Proposals for bars, restaurants in the vicinity
Astrid: Personal Task manager
Astro: Android File, Process and Application manager