Permissions.
Language barriers are cool sometimes, like pissed, I really like that one
Your question:
I'd think that by adding these users to the same group, owning that directory and all subdirectories to this group, and allowing world perm's on it should give you the desired "permissions" you'd want.
So let's say you have Tom, John, Rob, and Carl. The folder you want to give everyone permissions to is /mnt/stuff
So we'd need to create a group:
vi /etc/group
And call it whatever you'd like, give it a special GID, I'd say something like 77777. Just something that isn't in use, and never will be by any normal user/process.
So now the last few lines in your /etc/group file might look like this:
users::100:tom,rob,carl,john
console:x:101:
newgroup:x:77777:tom,rob,carl,john
Ok, so now you need to own the directory and it's subfolders:
chown -R nobody:newgroup /mnt/stuff
This makes nobody the owner, and newgroup the group owner. Now we will chmod the directory and it's sub:
chmod 2777 -R /mnt/stuff
Now everyone in newgroup should be able to read/write/execute everything in the directory and it's subdir's. And from the post from niknah I am assuming the 2 before the 777 makes each new file have the same group ownership as the original folder.
Ok, so now I think that's it...
Cool