Re: BUG #10347: Can't write password to psql or pg_dump

On Sun, May 18, 2014 at 12:23:24PM +0200, Andres Freund wrote:
> On 2014-05-16 20:34:09 +0000, derek_ealy(at)rapid7(dot)com wrote:
> > On Windows systems the psql or pg_dump process always hangs after sending
> > the password to stdin of the process.
> >
> > I've gotten around this problem by setting an environment variable before
> > exec'ing the process. I set OSTYPES=msys. This forces psql to use stdin when
> > reading the password.
>
> I think the important point - and why I asked for a bugreport after
> talking about it on irc - is that sprompt.c on windows uses
> CONIN$/CONOUT$ for io. Ignoring stdin/stdout except when the OSTYPE is
> set to msys. Given that CONIN$/OUT seem to refer to the shell that
> started a processtree from a shell that doesn't seem to be optimal.

That code is trying to mimic the non-Windows behavior, which is to interact
with /dev/tty when available. Unfortunately, CONIN$/CONOUT$ are ~always
nominally available, but they may not route to anything visible to the user.
The OSTYPE test is a crude attempt to anticipate that problem.
IsWindowVisible(GetConsoleWindow()) looked more reliable, but it still didn't
cover everything:
http://www.postgresql.org/message-id/flat/20121010110555(dot)GA21405(at)tornado(dot)leadboat(dot)com

--
Noah Misch
EnterpriseDB http://www.enterprisedb.com