Add a number of documentation files, mostly for SSL routines, but also
for a few BIO routines.
Submitted by Lutz Jaenicke <Lutz.Jaenicke@aet.TU-Cottbus.DE>

doc/ssl/SSL_write.pod

diff --git a/doc/ssl/SSL_write.pod b/doc/ssl/SSL_write.pod
new file mode 100644
index 0000000..9b433c0
--- /dev/null
+++ b/doc/ssl/SSL_write.pod
@@ -0,0 +1,66 @@
+=pod
+
+=head1 NAME
+
+SSL_read - Write bytes to a TLS connection.
+
+=head1 SYNOPSIS
+
+ #include <openssl/ssl.h>
+
+ int SSL_write(SSL *ssl, char *buf, int num);
+
+=head1 DESCRIPTION
+
+SSL_write() writes B<num> bytes from the buffer B<buf> into the specified
+B<ssl>. If necessary, SSL_write() will negotiate a TLS session, if
+not already explicitely performed by SSL_connect() or SSL_accept(). If the
+peer requests a re-negotiation, it will be performed transparently during
+the SSL_write() operation. The behaviour of SSL_write() depends on the
+underlying BIO. 
+
+If the underlying BIO is B<blocking>, SSL_write() will only return, once the
+write operation has been finished or an error occured.
+
+If the underlying BIO is B<non-blocking>, SSL_write() will also return,
+when the underlying BIO could not satisfy the needs of SSL_write()
+to continue the operation. In this case a call to SSL_get_error() with the
+return value of SSL_write() will yield SSL_ERROR_WANT_READ or
+SSL_ERROR_WANT_WRITE. As at any time a re-negotiation is possible, a
+call to SSL_write() can also cause write operations! The calling process
+then must repeat the call after taking appropriate action to satisfy the
+needs of SSL_write(). The action depends on the underlying BIO. When using a
+non-blocking socket, nothing is to be done, but select() 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.
+
+=head1 RETURN VALUES
+
+The following return values can occur:
+
+=over 4
+
+=item E<gt>0
+
+The write operation was successfull, the return value is the number of
+bytes actually written to the TLS connection.
+
+=item 0
+
+The write operation was not successfull. Call SSL_get_error() with the return
+value B<ret> to find out, whether an error occured.
+
+=item -1
+
+The read operation was not successfull, because either an error occured
+or action must be taken by the calling process. Call SSL_get_error() with the
+return value B<ret> to find out the reason.
+
+=back
+
+=head1 SEE ALSO
+
+L<SSL_get_error(3)|SSL_get_error(3)>, L<SSL_read(3)|SSL_read(3)>,
+L<ssl(3)|ssl(3)>, L<bio(3)|bio(3)>
+
+=cut