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+In the datalad test suite, a test involving one of our special remotes
+hangs after 7245a9ed5 (Improve shutdown process for external special
+remotes and external backends, 2020-11-02).  The hang depends on the
+remote program creating an SSH socket but not cleaning it up on
+failure.  That's being addressed on our end
+(<https://github.com/datalad/datalad/pull/5151>).
+
+While that's clearly bad handling on the part of datalad's special
+remote, I'm opening this bug report in case the above stall indicates
+that 7245a9ed5 brings an increased susceptibility to hanging that's
+worth worrying about.  Based on 7245a9ed5's commit message, it sounds
+like that resolved some hanging on Windows (and generally sounds like
+a good change), so it probably makes sense keep that at the expense of
+hanging that is restricted to buggy special remotes.  But I don't have
+a good enough understanding of the issue to know if it's limited to
+misbehaving special remotes, or if perhaps there's a way to avoid both
+hangs.
+
+In case it's helpful, here's a demo that tweaks the example special
+remote to trigger a hang:
+
+[[!format sh """
+set -eu
+
+ga_srcdir="$(realpath "${1?requires git-annex source directory as first argument}")"
+host="${2?requires ssh host as second argument}"
+cd "$(mktemp -d "${TMPDIR:-/tmp}"/gx-testremote-XXXXXXX)"
+top="$PWD"
+
+mkdir bin
+git -C "$ga_srcdir" cat-file -p cfae74ae25a791a8dbf8b476fe17d5c6feacd8b0 \
+    >bin/git-annex-remote-foo
+
+# Open a socket in setupcreds().
+cmd="ssh -fN -o ControlMaster=auto -o ControlPersist=15m -o ControlPath=$top/socket $host"
+sed -i "s|setupcreds () {|&\\n\\t$cmd|" bin/git-annex-remote-foo
+
+chmod +x bin/git-annex-remote-foo
+export PATH="$top/bin:$PATH"
+
+git annex version
+git init a
+(
+    cd a
+    git annex init main
+    # This will trigger an INITREMOTE-FAILURE failure because
+    # MYPASSWORD and MYLOGIN are not set.  This hangs after 7245a9ed5.
+    git annex initremote d --debug \
+        type=external externaltype=foo directory="$top/d" encryption=none
+)
+"""]]
+
+```
+$ sh /tmp/gx-failed-dir-hang.sh ~/src/haskell/git-annex smaug
+git-annex version: 8.20201103
+build flags: Assistant Pairing Inotify MagicMime Feeds Testsuite S3 WebDAV
+dependency versions: aws-0.20 bloomfilter-2.0.1.0 cryptonite-0.25 DAV-1.3.4 feed-1.2.0.1 ghc-8.6.5 http-client-0.6.4 persistent-sqlite-2.10.5.2 uuid-1.3.13
+[... 40 lines ...]
+[2020-11-12 11:40:01.886013862] /tmp/gx-testremote-3MudMuQ/bin/git-annex-remote-foo[1] --> SETCONFIG directory /tmp/gx-testremote-3MudMuQ/d
+[2020-11-12 11:40:02.451619481] /tmp/gx-testremote-3MudMuQ/bin/git-annex-remote-foo[1] --> INITREMOTE-FAILURE You need to set MYPASSWORD and MYLOGIN environment variables when running initremote.
+```
+
+[[!meta author=kyle]]
+[[!tag projects/datalad]]