How do I enable a group of users to edit files in Ubuntu var/www?

I’m hoping someone will be able to direct or help me understand how I can enable multiple users to edit the same files/folders in Ubuntu EC2 server (11.10).

I currently use Transmit, the Terminal window, and WordPress to upload files to the WP folder. To use WP from it’s “Dashboard panel” I find I have to chown the WP directory to the www-data user and whenever I want to upload files through Transmit to the WP directory I have to chown to the ubuntu user to allow this to happen.

I’ve tried chgrp to the WP folder upon adding www-data and ubuntu to a common group, but it still doesn’t allow each user to edit/delete files without chown.

How can I allow a group of users in Ubuntu to be able to edit/delete files in the same directory?

Thanks for your help,
Ryan

If you set the set-Group-ID bit on a directory files created in that directory will inherit the same group as the directory.

If your umask is set to allow members of the group to edit files this should solve your problem.

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