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+=pod
+
+=head1 NAME
+
+BIO_new_CMS - CMS streaming filter BIO
+
+=head1 SYNOPSIS
+
+ #include <openssl/cms.h>
+
+ BIO *BIO_new_CMS(BIO *out, CMS_ContentInfo *cms);
+
+=head1 DESCRIPTION
+
+BIO_new_CMS() returns a streaming filter BIO chain based on B<cms>. The output
+of the filter is written to B<out>. Any data written to the chain is
+automatically translated to a BER format CMS structure of the appropriate type.
+
+=head1 NOTES
+
+The chain returned by this function behaves like a standard filter BIO. It
+supports non blocking I/O. Content is processed and streamed on the fly and not
+all held in memory at once: so it is possible to encode very large structures.
+After all content has been written through the chain BIO_flush() must be called
+to finalise the structure.
+
+The B<CMS_STREAM> flag must be included in the corresponding B<flags>
+parameter of the B<cms> creation function.
+
+If an application wishes to write additional data to B<out> BIOs should be
+removed from the chain using BIO_pop() and freed with BIO_free() until B<out>
+is reached. If no additional data needs to be written BIO_free_all() can be
+called to free up the whole chain.
+
+Any content written through the filter is used verbatim: no canonical
+translation is performed.
+
+It is possible to chain multiple BIOs to, for example, create a triple wrapped
+signed, enveloped, signed structure. In this case it is the applications
+responsibility to set the inner content type of any outer CMS_ContentInfo
+structures.
+
+Large numbers of small writes through the chain should be avoided as this will
+produce an output consisting of lots of OCTET STRING structures. Prepending
+a BIO_f_buffer() buffering BIO will prevent this.
+
+=head1 BUGS
+
+There is currently no corresponding inverse BIO: i.e. one which can decode
+a CMS structure on the fly.
+
+=head1 RETURN VALUES
+
+BIO_new_CMS() returns a BIO chain when successful or NULL if an error
+occurred. The error can be obtained from ERR_get_error(3).
+
+=head1 SEE ALSO
+
+L<ERR_get_error(3)>, L<CMS_sign(3)>,
+L<CMS_encrypt(3)>
+
+=head1 HISTORY
+
+BIO_new_CMS() was added to OpenSSL 1.0.0
+
+=head1 COPYRIGHT
+
+Copyright 2008-2016 The OpenSSL Project Authors. All Rights Reserved.
+
+Licensed under the OpenSSL license (the "License").  You may not use
+this file except in compliance with the License.  You can obtain a copy
+in the file LICENSE in the source distribution or at
+L<https://www.openssl.org/source/license.html>.
+
+=cut