What is the easiest way to insert copyright notice in lots of PHP files.
It's not possible to do it manually.
It's better to have a separate
However, if you really want to do this, you can use a script:
Assuming you use Linux or an UNIX environment
You should have some kind of templating mechanism in place (at the very least, a header.php and footer.php that you include in every page).
If you do, then it should be trivial to include a 'copyright message' in a part of the page that gets included everywhere already (typically, the footer); how exactly you do this depends on the template system.
If you don't have a template mechanism, I suggest you start adding one right away.
In case you still need to automate the file editing part, consider using sed; it's an excellent tool for the job (although the learning curve is a bit steep if you aren't used to regular expressions).