I was so sure of myself, I thought I knew about permissions. Until someone asked me this.

Having these users:

```
User   Group
----   -----
juan   juan
pedro  pedro
maria  maria
jose   jose
miguel miguel
eric   eric
lola   lola
paola  paola       

```

This directory: `/opt/privado` with Owner = `juan:juan`

Permissions:

```
juan 111
pedro  110
maria and jose 101
miguel and eric 100
lola   000

```

There are no common permissions for creating a group `myGroup` and assigning, for example, 110 because I have different permissions for a different group of users. How can this be done on Unix? Really the issue is for Linux, but maybe it is the same solution.