7.0.0.18
Windows Native SSL: Secure Communication
The 
net/win32-ssl module
offers a fraction of the functionality of 
openssl and
works only on Windows, but it has the advantage that it works before
OpenSSL libraries are installed.
 | 
 | 
|   hostname : string? | 
|   port-no : (integer-in 1 65535) | 
|    | client-protocol |   | : |   | | (or/c 'secure 'auto |  |       'sslv2-or-v3 'sslv2 'sslv3 'tls 'tls11 'tls12) |  
  |  |   |   |   | = |   | 'auto |  
  | 
Like 
ssl-connect, but without support for client contexts.
If hostname verification is enabled via 'secure, the peer
server’s certificate is checked against hostname.
修改于package base的6.3.0.12版本:Added the #:hostname argument.
A boolean value that reports whether the Windows native SSL library was
successfully loaded. Calling 
win32-ssl-connect, etc
. when this
value is 
#f will raise an exception.