chgrp: operation not permitted even though I own the file!
 

I want to chgrp a file (from my default user group) to another group of which I'm a member. So:
Why can't I change it?
Interstingly, root can change the group, and then the regular user can change it back to the user's default group.

I'm using Red Hat 7.2 on a ext3 file system.

tried chown?

chup:
Yes; the error occurs if I try:
on a file that I both own and is in my default user group. Also if I just try to change the user.
(I'm assuming that I can't chown on a file I don't own... so I didn't test that!)

CHOWN SYNTAX = chown [options] user[:group] file...

CHGRP SYNTAX = chgrp [options] group file...

Chown does what chgrp can, plus its older so you know it will work better.
Note, that was right from the manual pages you should be reading =P

type ls -l so we can see the file

To change the group ownership of a file to another group you have to be a member of that group or root. That is why you are getting the Operation not permitted error.

tearinox: That's what I'm doing (with no [options]); I've been over the man pages several times other web pages several times. I'm pretty sure the syntax is right.

Here's an explicit example: (my username is "will" and I want to change to group "ezra")

darthtux:
I'm a member of the group. This is the last line of /etc/group:
In any case, I can change the group membership of testfile back to "will", after root has changed it to "ezra". So I think the system recognizes I'm in the target group.

I posted in the newbie forum because I figured it was something common but not obvious; I'm not an idiot (most of the time).

What about
chown will.ezra file

darthtux:
Nope, same "operation not permitted result".

Thanks for everyone's comments. I'm starting to think its something uniquely screwy with my RedHat 7.2 installation. (Although, otherwise, I haven't had problems with it.) I'll try it out on another system and report back later.
If anyone has any weird ideas, feel free to tell me!

I found the same results on my RedHat 9.0 system, too. Weird.

Apparently I needed to reboot (on both 7.2 and 9.0) to get the system to fully (?) recognize the new group settings. I added the group "ezra" with groupadd, and then manually edited /etc/group to put user "will" in group "ezra". Rebooting let me change the group permission, as sought above.

Perhaps I should have used "usermod -G ezra will" to do this.

Groups updating
 

Groups don't update until you log-in again. So even if you edit /etc/groups, you still have to logout and log in again (or just run another shell inside the current one. That should give the same effect :-)

This had me stumpped too and I have been using Linux for years, both server and desktop.

You do need to login again.

scraimer running 'bash' and then trying to chgrp again doesn't work either, unfortunately.

You can also use to change to the group without a restart/logout (actually changes your primary group to <group>).

What I was wondering: why do you have to be part of the group <target> in order to be able to change the current group ownership to <target>? Some kind of a security mechanism which I'm overlooking?