/etc/group changes don't take effect immediately

[Alphonse Ogulla <ogulla@uonbi.ac.ke>]

Hi all,
In an effort to run ppp as non root, I had to include my normal user id in the 
group 'dip' by directly editing /etc/group using vi. However, on saving and 
exiting /etc/group, I still could *not* access files owned by user root and 
available to users in group dip whilst using my normal uid. Just as I was 
about to give up, I decided to exit the shell and log in once again and to my 
amazement, I now could read files in /etc/ppp/peers directory whose 
permission is as follows:-

user@fep:/etc/ppp$ ls -ld peers
drwxr-s---	2 root	dip		4096 Oct	2 12:06 peers

How does one explain this? Is the file /etc/group cached somewhere and updated 
only so often? How can the changes be forced to take effect immediately 
without exiting and logging in again?

Regards,

Alphonse Ogulla
Nairobi, Kenya

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