Hi all.

I created a group 'developers'. Then i created 2 users dev1, dev2. Now i created a file 'test.txt'. Using chgrp and chown, i changed owner to dev1 and group to developers. So far so good. Now i logged in as dev2 and tried to change the permissions of this file as follows

chmod 440 test.txt

But it said, operation not permitted.

1) is it because dev1 is the owner ?
2) how can i make dev2 to use chmod ?
3) dev2 has complete access to test.txt file, but still it wasnt able to use chmod. How shall i know which other commands dev2 will not be able to use ?

Note: by mistake i put the wrong title. Sorry for that :-(

You don't say what the original permission bits are on the file. It appears that dev2 only has read access to the file by means of group permissions. You would need to give write permission to group in order for dev2 to be able to change the file.

Actually only the owner of the file can chmod the file. Even if the group and other had write permissions, the only one that can chmod the file is still just the owner.