convert file extension

[jr_yeo]

how to convert one file extension to another in a single command line in linux?
i want to convert *.html to *.php recursively and retain the original file.

[Twey]

Well, one way, perhaps not the most elegant:

find -iname '*.php' /top/directory -exec cp {} `dirname {}`/`basename {} .php`.html \;

I'm pretty sure something better is possible in zsh with regular expressions, but it's too early for the man pages to make sense.