Re: incron fails after dealing with changes done by useradd or userdell

Hi Patryk,
this kind of problems was discussed many times here and almost always
these problems were classified as "correct but unexpected behavior" (not
a bug). Please use "strace" and send its output to the mailing list. I
think useradd may behave different ways and there is no chance to move
forward without more detailed information. Thanks.

Lukas

> On 03/07/2011 05:05 PM, Andrew Pollock wrote:
>> On Mon, Mar 07, 2011 at 02:46:49PM +0100, Patryk wrote:
>>> Hello,
>>>
>>> I gave incron 0.5.8 a try.
>>>
>>> # `incrontab -e`
>>> /etc/passwd IN_CLOSE_WRITE /send/me/an/email
>>>
>>> useradd would trigger this immediately, sending 2 notification emails. After that incron
>>> would just hang and ignore any changes to the passwd file. The same happens with
>>> /etc/group or userdel, however echo text> /some/other/file works all the time without
>>> crashing anything.
>>>
>> I don't think this is a bug with incron.
>>
>> I think you should strace useradd and see what it's doing. I think you may
>> find that it's creating a temporary file with the new user in it, and then
>> moving it over the top of the current passwd file. This isn't going to be
>> considered an IN_CLOSE_WRITE by incron, which is why you're not seeing your
>> job execute.
>>
>> Sure enough, strace (on my system) reveals that useradd manipulates an
>> /etc/passwd+ and an /etc/passwd-, and rename()s /etc/passwd+ to /etc/passwd.
>>
>> regards
>>
>> Andrew
> Hi Andrew,
>
> From your explanation I can conclude that it should never trigger, while it triggers once
> and then stops reacting completely.
> Are you sure this is not a bug?
>
> regards,
>
> Patryk
>
Received on Tue Jun 05 2012 - 22:14:21 CEST