Sharing files with multiple users on single iMac

Question

THIS IS a REPOST from another location - more appropriate "thread"
After switching to Mac from a PC about a month ago (& not being technologically over-adept), I have finally succeeded in creating separate "User" accounts on my iMac (1 admin, 1 standard, 1 managed) to allow the 3 users in my household to create their own workspace. However, now I would like to allow them to access all files from some applications - iTunes, iPhoto, Address Book, etc. - and some of the files within Numbers, Pages, & Keynote (that were theirs to start with...but they were working on in "my" admin space before establishing separate Users.) As an additional challenge, I'd still like to have access to their files...for monitoring purposes...as we go forward. I've "searched" the Apple support files and found reference to some of this but (1) I can't seem to figure out how to move the files into the Public Folder (I did one, then logged in as another User & it wasn't there...) and (2) If they access files from the Public Folder, will they need to specifically save them back there when done? -- my other users will NEVER remember to put something back where they got it...

Answer 1

You can give each user read and write permissions to just that folder, or to everything in it. But that will not stick to any new files that are added to the folder hierarchy after that point. When new files are created they are read and write for the creator, and read only for all others. If you want to change that it must be done manually for each new file that you add.
There is a way to get around this, and make every file/folder added to a folder hierarchy automatically get full read and write permission for the users you specify. It requires setting up ACLs. Do it this way:
1. Make a new subfolder in /Users/Shared. Call it something like /Users/Shared/sharefolder. Move all the files you want to share into this folder.
2. Go to System Preferences and unlock the Accounts pref pane. Click the + button. Make a new group (select "group" from the drop down menu). Call it something like "sharegroup". Add the users you want to that group.
3. Log in to an admin account. Launch Terminal. Paste in all three of these lines at the same time and then press Return:
sudo chmod -R +a "sharegroup allow delete,chown,list,search,add_file,\
addsubdirectory,delete_child,file_inherit,directoryinherit" \
/Users/Shared/sharefolder
Enter your admin password when prompted and press return again. You are done. The users in the sharegroup can all now read and write everything in the sharefolder. They will also be able to read and write any file that is newly created or copied into the sharefolder from that point on.
NOTE: After setting this up, and you want to add more files to the sharefolder, be aware that files that already exist outside the sharefolder WON'T inherit the new permissions if they are simply moved in (i.e. drag with Finder). They must be copied in. Hold down the option key when dragging files into the sharefolder. That will ensure that a new copy will be made, and the permissions will inherit properly. You can then delete the old copy of the file from its previous location.
I hope this helps.