Unix group problem

Hi everyone,

I encountered a strange problem when setting up user groups, I have three users in the default group, A, B, and C, I created a new group for A, while A, B, C are still in the default group. After that I changed all files under A directory to the new group. Since A is not in same group with B, C, now user B, C are not supposed to view A’s files, right?

But in my case, B, C can still view A’s files…Why is that?


Yes, files can be view by users not belonged to the new group…