BuddyPress.org

Where do you want to write the code – is it in a file in your child theme?

If the files are in the same directory, e.g. in your child theme folder, use something like:

locate_template( array( ‘myfile.php’ ), true )

It sounds though as though you are wanting to modify code in bp-default. You shouldn’t be modifying bp-default! All your changes should be in your child theme.