This article describes how to write and execute a "Hello World" bash script on Linux (Fedora).  1. the prerequisitesa text editor of your choice (e.g. vi)the bash shell
make sure you have installe [ ... ]

Solution: make sure that session_start() is the first statement in your PHP script. Even a  white space or or any other characters before session_start() or even before <?PHP tag will result in an [ ... ]