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Date: Wed, 28 May 2008 16:02:16 +0300
From: Markku Savela <msa@moth.iki.fi>
Message-Id: <200805281302.m4SD2GGw012289@burp.tkv.asdf.org>
To: linux-kernel@vger.kernel.org
Subject: in_group_p test for another process?
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If I have a PID and some GID at hand, how do I find whether the OHTER
process identified by PID has the GID in its supplementary set of
groups?

I can find the "in_group_p" test, but that does it only for current process.

Do I have to write my own function that uses the "tasklist_lock",
finds task by "find_task_by_pid", and then calls
"groups_search(task->group_info, gid)"?

Can I do this in a module, or do I have to patch the "kernel/sys.c"
myself for a privately modified version of the kernel?