Re: BUG #13594: pg_ctl.exe redirects stderr to Windows Events Log if stderr is redirected to pipe - Mailing list pgsql-bugs

On Mon, Aug 31, 2015 at 11:56 PM, Egon Kocjan wrote:
> On 31.8.2015 8:51, Michael Paquier wrote:
>> Egon, would the patch attached help in your case?
>>
>
> diff -ur postgresql-9.6devel.orig\src\bin\pg_ctl\pg_ctl.c
> postgresql-9.6devel\src\bin\pg_ctl\pg_ctl.c
> --- postgresql-9.6devel.orig\src\bin\pg_ctl\pg_ctl.c    Mon Aug 31 13:16:51
> 2015
> +++ postgresql-9.6devel\src\bin\pg_ctl\pg_ctl.c    Mon Aug 31 15:12:54 2015
> @@ -215,7 +215,7 @@
>       * On Win32, we print to stderr if running on a console, or write to
>       * eventlog if running as a service
>       */
> -    if (!pgwin32_is_service())    /* Running as a service */
> +    if (pgwin32_is_service())    /* Running as a service */
>      {
>          char        errbuf[2048];        /* Arbitrary size? */

This one is obviously a stupid mistake of my patch :)

> @@ -2131,6 +2131,9 @@
>      progname = get_progname(argv[0]);
>      set_pglocale_pgservice(argv[0], PG_TEXTDOMAIN("pg_ctl"));
>      start_time = time(NULL);
> +
> +    write_stderr("%s: test test\n",
> +                     progname);
>
>      /*
>       * save argv[0] so do_start() can look for the postmaster if necessary.
> we
>
>
> 1) It now works ok for development under regular account.

Thanks for the additional tests, that's still a win so this patch is a
good thing. Relying on isatty is definitely something that we should
treat as a bug here and backpatch. On master and REL9_5_STABLE, what I
sent previously, with the call of pgwin32_is_service fixed in pg_ctl.c
is fine. For back branches, we could simply copy pgwin32_is_service in
pg_ctl.c and rely on that. It seems like the safer approach. Thoughts
from other hackers on the matter?

> 2) However there is no output on stderr when pg_ctl is running as a
> subprocess of a service. So I would still have to patch pg_ctl if I want
> stderr. I haven't looked into elog.c yet, maybe stderr from there would be
> good to have as well? So far, pg_ctl output and pg_logs\* was enough for me
> to debug the installations. Technically, I could also monitor Windows event
> log and dump events on the fly into my report file. But it seems simpler to
> just patch PostgreSQL locally to force stderr and reuse all the logic from
> the Unix port...

I wished we had such a switch a couple of times and I have as well
some code paths that would benefit a redirection of those logs to
stderr instead of the event log. Still this sounds like a new feature
to me. Hence, what about for example adding a Windows-only option that
can be used to enforce where logs are redirected, let's say
--log-output with the following values:
- default, which is what we have now
- stderr, to enforce the output to stderr
- eventlog, to enforce redirection to the event logs.
Would you like to work on this patch?
Regards,
--
Michael