[TYPO3-dev] BE module _DISPATCH - BACK_PATH doesn't work with symlinked core

[Jan Bednarik]

Hi all,

I have changed CoolUri's BE modules to be _DISPATCH and I use this code 
to include necessary classes:

require_once $BACK_PATH . t3lib_extMgm::extRelPath('cooluri') . 
'cooluri/manager/linkmanager.Main.php';

However, it's been reported to me that this doesn't work when typo3 
directory is symlinked to typo3_src/typo3. The path is translated to

../typo3conf/ext/cooluri/...

but since mod.php is inside typo3_src/typo3, it doesn't work.

So what is the correct approach? For required I could use 
dirname(__FILE__), but this won't work when I e.g. include CSS:

$this->pageRenderer->addCssFile($BACK_PATH . 
t3lib_extMgm::extRelPath('cooluri') . 'mod1/style.css');

Please help.

BTW, are there any resources on how to write BE modules?

Thanks

Jan