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SSL_get_error(3)		    OpenSSL		      SSL_get_error(3)

       SSL_get_error - obtain result code for TLS/SSL I/O operation

	#include <openssl/ssl.h>

	int SSL_get_error(const SSL *ssl, int ret);

       SSL_get_error() returns a result code (suitable for the C "switch"
       statement) for a preceding call to SSL_connect(), SSL_accept(),
       SSL_do_handshake(), SSL_read(), SSL_peek(), or SSL_write() on ssl.  The
       value returned by that TLS/SSL I/O function must be passed to
       SSL_get_error() in parameter ret.

       In addition to ssl and ret, SSL_get_error() inspects the current
       thread's OpenSSL error queue.  Thus, SSL_get_error() must be used in
       the same thread that performed the TLS/SSL I/O operation, and no other
       OpenSSL function calls should appear in between.	 The current thread's
       error queue must be empty before the TLS/SSL I/O operation is
       attempted, or SSL_get_error() will not work reliably.

       The following return values can currently occur:

	   The TLS/SSL I/O operation completed.	 This result code is returned
	   if and only if ret > 0.

	   The TLS/SSL connection has been closed.  If the protocol version is
	   SSL 3.0 or higher, this result code is returned only if a closure
	   alert has occurred in the protocol, i.e. if the connection has been
	   closed cleanly.  Note that in this case SSL_ERROR_ZERO_RETURN does
	   not necessarily indicate that the underlying transport has been

	   The operation did not complete; the same TLS/SSL I/O function
	   should be called again later.  If, by then, the underlying BIO has
	   data available for reading (if the result code is
	   SSL_ERROR_WANT_READ) or allows writing data (SSL_ERROR_WANT_WRITE),
	   then some TLS/SSL protocol progress will take place, i.e. at least
	   part of an TLS/SSL record will be read or written.  Note that the
	   retry may again lead to a SSL_ERROR_WANT_READ or
	   SSL_ERROR_WANT_WRITE condition.  There is no fixed upper limit for
	   the number of iterations that may be necessary until progress
	   becomes visible at application protocol level.

	   For socket BIOs (e.g. when SSL_set_fd() was used), select() or
	   poll() on the underlying socket can be used to find out when the
	   TLS/SSL I/O function should be retried.

	   Caveat: Any TLS/SSL I/O function can lead to either of
	   SSL_read() or SSL_peek() may want to write data and SSL_write() may
	   want to read data.  This is mainly because TLS/SSL handshakes may
	   occur at any time during the protocol (initiated by either the
	   client or the server); SSL_read(), SSL_peek(), and SSL_write() will
	   handle any pending handshakes.

	   The operation did not complete; the same TLS/SSL I/O function
	   should be called again later. The underlying BIO was not connected
	   yet to the peer and the call would block in connect()/accept(). The
	   SSL function should be called again when the connection is
	   established. These messages can only appear with a BIO_s_connect()
	   or BIO_s_accept() BIO, respectively.	 In order to find out, when
	   the connection has been successfully established, on many platforms
	   select() or poll() for writing on the socket file descriptor can be

	   The operation did not complete because an application callback set
	   by SSL_CTX_set_client_cert_cb() has asked to be called again.  The
	   TLS/SSL I/O function should be called again later.  Details depend
	   on the application.

	   Some non-recoverable I/O error occurred.  The OpenSSL error queue
	   may contain more information on the error.  For socket I/O on Unix
	   systems, consult errno for details.

	   A failure in the SSL library occurred, usually a protocol error.
	   The OpenSSL error queue contains more information on the error.

       ssl(3), err(3)

       SSL_get_error() was added in SSLeay 0.8.

1.0.2k				  2017-01-26		      SSL_get_error(3)