Automatically make shared files writable for others

The following procedure will create a shared folder, that will automatically grant users of a group read and write permissions to all files/folders copied to it.

Step 1: Go to System Preferences -> Accounts. Unlock the padlock and press the + button. Then, select "Group" from the drop down menu. Give the new group the name sharegroup. Add the users you want to the group.

Step 2: Create a folder in /Users/Shared to be used for sharing your files. If you already have a folder with files in it you want to use, move it to /Users/Shared.

Step 3: Log in to an administrator account and open Terminal. Paste in the following two lines at the same time:

sudo chmod -R +a "sharegroup allow delete,chown,list,search,add_file,\
addsubdirectory,delete_child,file_inherit,directoryinherit" \

Then press return. Then drag the folder to be shared into the Terminal window, and press return again. Enter the admin password when prompted and press return again.

When you are done, it is all set up. Any items that are *created in* or *copied to* that folder will automatically be read+write for all of the users in the group.

Please note that if you have any pre-existing files elsewhere on the same volume, they won't inherit the ACL settings if they are simply moved to the sharefolder. They must be copied or *newly created* there. *Holding down the option key* when dragging files there from another location should ensure that they are copied.

This is the 1st version of this tip. It was submitted on February 10, 2011 by Király.