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SSL_connect(3)
NAME
  SSL_connect - Initiate the TLS/SSL handshake with an TLS/SSL server

SYNOPSIS
  #include <openssl/ssl.h>

  int SSL_connect(
	  SSL *ssl );

DESCRIPTION
  The SSL_connect() function initiates the TLS/SSL handshake with a server.
  The communication channel must already have been set and assigned to the
  ssl by setting an underlying BIO.

NOTES
  The behavior of the SSL_connect() function depends on the underlying BIO.

  If the underlying BIO is blocking, the SSL_connect() function will only
  return once the handshake has been finished or an error occurred.

  If the underlying BIO is non-blocking, the SSL_connect() function will also
  return when the underlying BIO could not satisfy the needs of SSL_connect()
  to continue the handshake. In this case, a call to SSL_get_error() with the
  return value of SSL_connect() will yield SSL_ERROR_WANT_READ or
  SSL_ERROR_WANT_WRITE. The calling process then must repeat the call after
  taking appropriate action to satisfy the needs of SSL_connect().  The
  action depends on the underlying BIO. When using a non-blocking socket,
  nothing is to be done, but the select() function can be used to check for
  the required condition. When using a buffering BIO, like a BIO pair, data
  must be written into or retrieved out of the BIO before being able to
  continue.

RETURN VALUES
  The following return values can occur:

  1	  The TLS/SSL handshake was successfully completed.  A TLS/SSL
	  connection was established.

  0	  The TLS/SSL handshake was not successful but was shut down
	  controlled and by the specifications of the TLS/SSL protocol.	 Call
	  the SSL_get_error() function with the return value ret to find out
	  the reason.

  <0	  The TLS/SSL handshake was not successful, because a fatal error
	  occurred either at the protocol level or a connection failure
	  occurred. The shutdown was not clean. It can also occur if action
	  is needed to continue the operation for non-blocking BIOs. Call the
	  SSL_get_error() function with the return value ret to find out the
	  reason.

SEE ALSO
  Functions: SSL_get_error(3), SSL_accept(3), SSL_shutdown(3), ssl(3),
  bio(3), SSL_set_connect_state(3), SSL_do_handshake(3), SSL_CTX_new(3)

Index for Section 3

Alphabetical listing for S

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