The newgrp command

[Richard E Miles]

On Thu, 25 Aug 2005 08:24:05 +0700
Vidol Loeung <fedora.kh at undp.org> wrote:

> Thanks Richard. When I as a user used newgrp to switch myself to a new
> group, I of course gave the password of that group, which was assigned by
> the gpasswd comamnd as you mentioned. I also agree that, this command is
> rarely used and I think, it only makes sense when a user would like
> files/directories (s)he creates to belong to a particular group. Having the
> user as a member in each group is fine.
> 
> My question was out of curiosity as I was trying to experiment the newgrp
> command and found that it did not seem to work the way it should as its
> manual and documentations stated that the command is used to switch a user
> to a new group and requires the group password.
> 
> Let me give a scenario here:
> - I logged in as user 'joe'.
> - Then, I typed this command ('joe' is not a member of group 'users'):
>   $ newgrp users
>   Password:
>   newgrp: Permission denied
> 
> I've wondering what the group passwd command is used for and found that the
> newgrp command is the one that needs the group passwd. Now, when I tried it
> as above it did not work.
> 
> Would someone kindly clarify a bit more on the use of the newgrp command?
> 
> Regards,
> Vidol
> 
> ----- Original Message ----- 
> From: <rengland at europa.com>
> To: "For users of Fedora Core releases" <fedora-list at redhat.com>
> Sent: Wednesday, August 24, 2005 3:07 AM
> Subject: Re: The newgrp command
> 
> 
> > > Thank you Ben and Richard for yoru replies.
> > >
> > > Well, Ben you are right, root can switch to any group without having to
> > > give
> > > a password. I also discovered the same as what Richard said. However, in
> > > case an ordinary user is not a member of a particular group and she/he
> > > tries
> > > to use the newgrp command to switch to that group with correct password,
> > > it
> > > always gave the error message: Permission denied.
> > >
> > > Read a lot of docs on it but still could not help.
> > >
> > > Regards,
> > > Vidol
> > >
> > >
> > > ----- Original Message -----
> > > From: "Richard England" <rengland at europa.com>
> > > To: "For users of Fedora Core releases" <fedora-list at redhat.com>
> > > Sent: Tuesday, August 23, 2005 1:06 PM
> > > Subject: Re: The newgrp command
> > >
> > >
> > >>
> > >> Ben Stringer wrote:
> > >>
> > >> >On Tue, 2005-08-23 at 12:17 +0700, Vidol Loeung wrote:
> > >> >
> > >> >
> > >> >>Dear All:
> > >> >>
> > >> >>The newgrp command seems simple to use. However, I could not use it
> or
> > >> I
> > > did
> > >> >>not know how to use it.
> > >> >>
> > >> >>Could someone please explain me what teh problem is? I was logged in
> > >> as
> > > an
> > >> >>ordinary user and type the command:
> > >> >>$ newgrp users
> > >> >>It asked me for the group password and I entered it but it said:
> > > "Permission
> > >> >>denied".
> > >> >>
> > >> >>
> > >> >
> > >> >Hi Vidol,
> > >> >
> > >> >You will need to be the root user to run this command.
> > >> >
> > >> >Try this:
> > >> >
> > >> >$ su -
> > >> ># newgrp users
> > >> >
> > >> >Cheers, Ben
> > >> >
> > >> >
> > >> >
> > >> >>Regards,
> > >> >>Vidol
> > >> >>
> > >> >>
> > >> >>
> > >> I don't believe that is strictly true.  If the userid is included in
> > >> several groups, all the user has to do is type in "newgrp
> <newgrpname>".
> > >> However, if the user is NOT member of the group, then they are prompted
> > >> for the group password.
> > >>
> > >> Use the command "id" to find out what your primary group currently is,
> > >> and the command "groups" to find out what groups your userid is
> > >> currently a member of.
> > >>
> > >> --R
> > >>
> > >> --
> > >> fedora-list mailing list
> > >> fedora-list at redhat.com
> > >> To unsubscribe: http://www.redhat.com/mailman/listinfo/fedora-list
> > >
> > > --
> > > fedora-list mailing list
> > > fedora-list at redhat.com
> > > To unsubscribe: http://www.redhat.com/mailman/listinfo/fedora-list
> > >
> > >
> >
> >
> > I'm no expert on this but what password were you entering for the group?
> > Do you know what, if any password was assigned to the group?  It may or
> > may not be the same as you login passwd.
> >
> > You can modify the group password using gpasswd  (see the man page).  I
> > did not investigate to find out how the original (creation time) password
> > is set.
> >
> > I've only used a small number of groups  (3-4) on my personal machine and
> > I've added my userid to each so I've never had to use newgrp there.  At
> > work I don't have permissions to modify anything at this level so I've not
> > worked with it.
> >

see man newgrp.


-- 
Richard Miles
Federal Way WA. USA
registered linux user 46097