how does tee command implemented?
 

I am trying to understand how the tee command implemented. I need to use tee command in high speed logging application. where stdout and stderr has to be redirected to a file. here i am concerned about the performance. Is tee redirect the data character by character or by buffer?

There are several places you can find the source for any Linux command (tee, cat, ls, etc etc). For example:

http://www.thegeekstuff.com/2010/02/...linux-command/

http://www.gnu.org/software/coreutils/faq/