[Typo3-dev] Cannot modify header information - headers already sent

[Wolfgang Klinger]

 Hi!

 On Thu, 10 Nov 2005, Pedro Barbosa wrote the following:
> I'm  getting started in typo3 and i wanted to include php script.
> Justo for fun(or not) i created a calculator in php and when i open the 
> website i get the following warning:
> *Warning*: Cannot modify header information - headers already sent by 
> (output started at ..../scripts/calculadora.inc:41) in 
> */var/www/html/sigtest/typo3_src-3.8.0/typo3/sysext/cms/tslib/class.tslib_fe.php* 
> on line *2612*

 You use "echo" for output. That's not how it works with TYPO3. You need
 to return the content, TYPO3 "collects" all the pieces and sends it to
 the client when finished (plus some "headers" beforehand like a Cookie
 or something).


 kind regards
 Wolfgang