[erlang-questions] ssl:shutdown(Socket, write) unexpected behavior?

[Jay Doane]

I'm working on an erlang network file copier that should be able to
use either tcp or ssl, depending on its configuration.

The basic idea is that it listens on a specified port, and writes
anything it receives to a file, then with the *same* connection,
responds to the sender with some statistics, and finally closes the
connection.  A demonstration version can be found here:
https://gist.github.com/jaydoane/65dc6b005788af3c49e2866ea7d03f09

For basic tcp, this can be achieved by the sender doing a
gen_tcp:shutdown(Socket, write) after sending the payload, which -- if
the receiving socket is configured with {exit_on_close, false} --
closes the connection in the sending direction, but leaves it open to
receive the response. For example, this test works:

1> netcopy:test(tcp).
Response #{bytecount => 393,checksum => 3827135813,path => "/tmp/netcp"}
ok

Unfortunately, trying to use ssl:shutdown/2 [1] in the same way seems to
close the connection for both writing and reading, and therefore the
attempt to use ssl:recv/3 fails:

2> netcopy:test(ssl).
Generating a 2048 bit RSA private key
................................................................+++
.................+++
writing new private key to '/tmp/netcopy/key.pem'
-----

=ERROR REPORT==== 8-Jun-2016::23:13:26 ===
Error in process <0.621.0> with exit value:
{{badmatch,{error,closed}},
 [{netcopy,listen,4,[{file,"netcopy.erl"},{line,38}]}]}
** exception error: no match of right hand side value {error,closed}
     in function  netcopy:sendfile/5 (netcopy.erl, line 88)
     in call from netcopy:test/1 (netcopy.erl, line 172)

After some research [2], I thought the problem might be related to using
a Mac, but I've gotten the same results on Ubuntu 14.04. I've also
seen this both with otp 18.3 and 19.0-rc2.

Is this possible to do using ssl?

Thanks,
Jay

[1] http://erlang.org/doc/man/ssl.html#shutdown-2
[2] https://docs.python.org/2/library/socket.html#socket.socket.shutdown
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