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Date: Thu, 22 Feb 2024 20:11:25 +0100
From: Corinna Vinschen <corinna-cygwin@cygwin.com>
To: cygwin@cygwin.com
Subject: Re: Switching groups with newgrp - how to get the new group with
 |GetTokenInformation()| ?
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On Feb 22 18:38, Roland Mainz via Cygwin wrote:
> Hi!
> 
> ----
> 
> If I switch the current user's group with /usr/bin/newgrp, how can a
> (native) Win32 process use
> |GetTokenInformation(GetCurrentThreadToken(), ...)| to find out which
> group is the new "current group" (e.g. which |TokenInformationClass|
> should I use) ?

  PSID sidbuf = (PSID) alloca (SECURITY_MAX_SID_SIZE);
  NTSTATUS status;
  ULONG size;

  status = NtQueryInformationToken (hProcToken, TokenPrimaryGroup,
                                    sidbuf, SECURITY_MAX_SID_SIZE,
				    &size);


Corinna