[ERRO keybase standard.go:225] 0ac GETPIN response didn't start with D; got "ERR 83918950 Inappropriate ioctl for device <Pinentry>" when decrypting

Whenever I try to decrypt from my pasteboard, I get:

```
2016-02-18T07:45:35.344280 ▶ [DEBU keybase pinentry.go:172] 09f - pinentryInstance::Init() ->
2016-02-18T07:45:35.344741 ▶ [DEBU keybase pinentry_osx.go:59] 0a0 | Error setting pinentry cache-id OPTION: Response to OPTION was ERR 83886254 Unknown option
2016-02-18T07:45:35.344774 ▶ [DEBU keybase pinentry_osx.go:60] 0a1 | Not using secret store as a result.
2016-02-18T07:45:35.344856 ▶ [DEBU keybase pinentry.go:96] 0a2 - Pinentry::Get() -> GETPIN response didn't start with D; got "ERR 83918950 Inappropriate ioctl for device "
2016-02-18T07:45:35.347009 ▶ [DEBU keybase log.go:30] 0a3 - PromptAndUnlock -> ERROR: GETPIN response didn't start with D; got "ERR 83918950 Inappropriate ioctl for device "
2016-02-18T07:45:35.347230 ▶ [DEBU keybase log.go:30] 0a4 - GetSecretKeyAndSKBWithPrompt() -> ERROR: GETPIN response didn't start with D; got "ERR 83918950 Inappropriate ioctl for device "
2016-02-18T07:45:35.347441 ▶ [DEBU keybase log.go:30] 0a5 - GetSecretKeyWithPrompt() -> ERROR: GETPIN response didn't start with D; got "ERR 83918950 Inappropriate ioctl for device "
2016-02-18T07:45:35.347612 ▶ [DEBU keybase log.go:30] 0a6 - SaltpackDecrypt::Run -> ERROR: GETPIN response didn't start with D; got "ERR 83918950 Inappropriate ioctl for device "
2016-02-18T07:45:35.347803 ▶ [DEBU keybase log.go:30] 0a7 - RunEngine(SaltpackDecrypt) -> ERROR: GETPIN response didn't start with D; got "ERR 83918950 Inappropriate ioctl for device "
2016-02-18T07:45:35.452256 ▶ [DEBU keybase globals.go:252] 0a8 Calling shutdown first time through
2016-02-18T07:45:35.452433 ▶ [DEBU keybase login_state.go:944] 0a9 + Account "LoginState - Shutdown"
2016-02-18T07:45:35.452546 ▶ [DEBU keybase login_state.go:946] 0aa - Account "LoginState - Shutdown"
2016-02-18T07:45:35.452609 ▶ [DEBU keybase globals.go:295] 0ab exiting shutdown code=0; err=
2016-02-18T07:45:35.452669 ▶ [ERRO keybase standard.go:225] 0ac GETPIN response didn't start with D; got "ERR 83918950 Inappropriate ioctl for device "
```

Full log attached:
[Inappropriate_ioctl.txt](https://github.com/keybase/keybase-issues/files/136471/Inappropriate_ioctl.txt)

Start by reproducing decryption from the pasteboard, then trace pinentry_osx.go:59-60 and pinentry.go:96 to see why the GETPIN response is an ioctl error instead of a D response. Compare the observed behavior with the attached log and confirm that pasteboard decryption can complete successfully without this error.

Written by the indexing model from the issue text.