Re: NSLog suddenly mirroring to /var/log/user.log, /var/log/warnings, and /var/log/syslog

[Lobron, David]

Thanks, Richard and Ivan.  Yes, it looks like I was logging so heavily to my 
regular partition that stderr was pointing to a filesystem that was 
periodically unwritable.  I've fixed it by reducing log frequency.

Thanks again,

David

> On Aug 4, 2016, at 10:38 AM, Richard Frith-Macdonald 
> <richard.frith-macdonald@brainstorm.co.uk> wrote:
> 
> 
>> On 4 Aug 2016, at 15:31, Richard Frith-Macdonald 
>> <richard.frith-macdonald@brainstorm.co.uk> wrote:
>> 
>> 
>>> On 4 Aug 2016, at 15:16, Lobron, David <dlobron@akamai.com> wrote:
>>> 
>>> Hi All,
>>> 
>>> I have an application that sends NSLog output to a custom location.  A few 
>>> days ago, the log lines suddenly started mirroring to /var/log/user.log, 
>>> /var/log/warnings, and /var/log/syslog.  I did not make any changes to my 
>>> program or the GNUStep runtime.  From a read of the NSLog docs, it seems 
>>> like this should not be able to happen.  Has anyone seen this before?  
>> 
>> 
>> I would be surprised if it's being mirrored (identical copies), but it seems 
>> quite likely that you are seeing output from syslog.
>> 
>> NSLog() will produce log output via syslog if *either* the GSLogSyslog user 
>> default is set *or* if the attempt to write to stderr fails.
>> 
>> So I would guess someone changed your user default or, something closed 
>> stderr, or stderr is pointing to something that's unwritable (eg a full 
>> filesystem).
> 
> PS. I guess the documentation is a little obscure ... the NSLog() 
> documentation points you to NSLogv(), which points you to 
> _NSLog_printf_handler, which describes the exact algorithm used for logging 
> ... or you can read the source :-)