chmod g+s ineffective

Norton Allen
Mon Jul 11 16:49:01 GMT 2022

On 7/10/2022 10:33 PM, Eliot Moss wrote:
> On 7/10/2022 10:17 PM, Chris Wagner wrote:
>>>> On 6/29/2022 9:18 AM, Norton Allen wrote:
>>>>>>> On one machine I have, chmod g+s fails to set the sticky bit. 
>>>>>>> The >>> command
>>>>>>> does not return any error, but ls -l continues to show the bit 
>>>>>>> not set.
>>>>>>>      $ mkdir foo
>>>>>>>      $ chgrp flight foo
>>>>>>>      $ chmod g+ws foo
>>>>>>>      $ ls -ld foo
>>>>>>>      drwxrwxr-x+ 1 nort flight 0 Jun 29 06:50 foo
>> Hi.  The permission bits are implemented as normal Window's DACLs 
>> (Discretionary Access List).  +s is implemented magically with the 
>> NULL SID.  You can view it from Explorer or with icacls.  Try 
>> checking the return code (echo $?) from chmod. Also try changing 
>> perms from Explorer.  You might not be able to set the NULL SID for 
>> some reason.
> I'd like to add that, for good reason, the Cygwin DACLs do not conform
> to the order of entries that some Windows tools prefer.  Don't let any
> Windows program/tool reorder the DACLs!  It will break the Cygwin
> functionality, and the Cygwin order does not break Windows functionality.
Right. My experience (Windows 10) is that I cannot change perms from 
Explorer if I don't let them reorder the perms (which I do not).

I have been separated from the machine that exhibits the problem, so I 
have not been able to try the solutions suggested, but expect to have it 
back in a week or so.

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