Changing UNIX primary group

Re: Changing UNIX primary group

"Justin Johnson" <justinjohnson@ fastmail.fm> wrote in message news:<mailman.1 060697959.27558 [email protected] >...[color=blue]
> I have a unix id that has group1 for a primary group, and group2, group3,
> and group4 for supplementary groups. I'd like to change my primary group
> before running certain commands. So sometimes I might want group2 to be
> the primary group, and other times group3 or group4.
>
> I saw the posix module's setgid method, but it failed for me unless I was
> running as root. Also it only accepts the gid, but I'd rather pass in
> the group name, or somehow lookup the gid based on the name.
>
> Does anyone know a way to do all of this?
> Thanks much.
> -Justin[/color]

These are not python solution;

1) make a setgid script and put your commands there, or
2) use shell commands;

echo "command1; command2;" | newgrp group2

-Inyeol

Re: Changing UNIX primary group

Thanks. I was hoping for a python solution though. :-( Does anyone
know of a way to do this in python?

On 13 Aug 2003 08:52:40 -0700, "Inyeol Lee" <Inyeol_lee@yah oo.com> said:[color=blue]
> "Justin Johnson" <justinjohnson@ fastmail.fm> wrote in message
> news:<mailman.1 060697959.27558 [email protected] >...[color=green]
> > I have a unix id that has group1 for a primary group, and group2, group3,
> > and group4 for supplementary groups. I'd like to change my primary group
> > before running certain commands. So sometimes I might want group2 to be
> > the primary group, and other times group3 or group4.
> >
> > I saw the posix module's setgid method, but it failed for me unless I was
> > running as root. Also it only accepts the gid, but I'd rather pass in
> > the group name, or somehow lookup the gid based on the name.
> >
> > Does anyone know a way to do all of this?
> > Thanks much.
> > -Justin[/color]
>
> These are not python solution;
>
> 1) make a setgid script and put your commands there, or
> 2) use shell commands;
>
> echo "command1; command2;" | newgrp group2
>
> -Inyeol
> --
> http://mail.python.org/mailman/listinfo/python-list[/color]

Re: Changing UNIX primary group

Okay, I'll have to do some more research. Maybe I *will* have to run the
script setuid root. Shucks! Thanks for the grp.getgrnam help. Just
what I needed. :-)

On Wed, 13 Aug 2003 14:11:01 -0500, "Jeff Epler" <jepler@unpytho nic.net>
said:[color=blue]
> On Wed, Aug 13, 2003 at 12:10:02PM -0600, Justin Johnson wrote:[color=green]
> > Thanks. I was hoping for a python solution though. :-( Does anyone
> > know of a way to do this in python?[/color]
>
> Unix doesn't let you setgid() to groups in the supplemental group list
> without the same permission needed to change to any group.
>
> But depending what you need to do, you might be able to use set-group-id
> directories. For instance, if I am group g1 and have a group list [g1,
> g2, g3], then I can read files readable by any of those groups, and
> create files in directories writable by any of those groups. But if you
> make a directory d2 that is setgid g2 and d3 setgid g3, then when I
> create a file in d2 it will belong to group g2.
>
> Barring that, you could modify the setgid() call in the kernel, to permit
> the change if the requested group is in the auxiliary group list.
> It looks like something you could do in an afternoon if you have the
> source for your kernel (bsd, linux, etc) and can program C.
>
> "Justin Johnson" <justinjohnson@ fastmail.fm> wrote in message
> news:<mailman.1 060697959.27558 [email protected] >...[color=green]
> > Also [setgid] only accepts the gid, but I'd rather pass in
> > the group name, or somehow lookup the gid based on the name.[/color]
>
> See grp.getgrnam(). Example:[color=green][color=darkred]
> >>> grp.getgrnam("u tmp")[/color][/color]
> ('utmp', 'x', 22, [])
>
> Jeff[/color]