Fix multiple threading bugs including #699 and #697

Author: lightvector

README.md

@@ -645,6 +645,12 @@ cli.set_ca_cert_path("./ca-bundle.crt");
 cli.enable_server_certificate_verification(true);
 ```
 
+Note: When using SSL, it seems impossible to avoid SIGPIPE in all cases, since on some operating systems, SIGPIPE
+can only be suppressed on a per-message basis, but there is no way to make the OpenSSL library do so for its
+internal communications. If your program needs to avoid being terminated on SIGPIPE, the only fully general way might
+be to set up a signal handler for SIGPIPE to handle or ignore it yourself.
+
+
 Compression
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