Jeff King venit, vidit, dixit 07.09.2016 10:39: > On Wed, Sep 07, 2016 at 10:27:34AM +0200, Michael J Gruber wrote: > >> Now, I can't reproduce C on Linux[*], so there is more involved. It >> could be that my patch just exposes a problem in our start_command() >> etc.: run-command.c contains a lot of ifdefing, so possibly quite >> different code is run on different platforms. > > Maybe, though my blind guess is that it is simply that on Linux we can > open /dev/tty directly, and console-IO on Windows is a bit more > complicated. > > You might also check your GPG versions; between gpg1.x and gpg2, the > passphrase input handling has been completely revamped. That's a good point to note. gpg1 asks for the passphrase (without use-agent), gpg2 always delegates to gpg-agent (and starts it on demand). On Linux, gpg-agent says you should export GPG_TTY=$(tty) to make gpg-agent find the tty, and claims it's not necessary on Win. In fact, it's not necessary on Linux either unless you want to use pinentry-curses. Alas, be it gpg1.4.21 or gpg2.1.13, whatever pinentry, I do get the passphrase prompt, even with curses (if GPG_TTY is set, which was necessary before any patches already). I put up a request for more input from the reporters in the github issue. I guess that's the best way to reach them. >> It would be great if someone with a Windows environment could help our >> efforts in resolving issue C, by checking what is actually behind[**]: I >> can't believe that capturing stderr keeps gpg from reading stdin, but >> who knows. Maybe Jeff of pipe_command() fame? I'll put him on cc. > > I know nothing about Windows, but I'd be surprised if gpg is reading > from stdin, as opposed to /dev/tty. It's probably more to do with how > gpg finds the "tty" on Windows (presumably it looks at stderr for that). > > Anyway, I wrote pipe_command() in such a way as to be prepared for > exactly this kind of thing, so it would be trivial to extend it to an > extra descriptor. The trouble is that run_command() doesn't understand > anything except stdin/stdout/stderr. We can open an extra pipe() before > calling run_command(), and make sure it is not marked CLOEXEC. I don't > know if there are other portability concerns, though. My suggestion to try "--status-fd=3" was meant to test whether the above could help: If fd=3 helps, then our capturing stderr is not the problem. (If fd=3 does not help then we still don't know...) Michael