Write a header to a stream using a serializer.

template<
    class SyncWriteStream,
    bool isRequest,
    class Body,
    class Fields>
std::size_t
write_header(
    SyncWriteStream& stream,
    serializer< isRequest, Body, Fields >& sr);
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template<
    class SyncWriteStream,
    bool isRequest,
    class Body,
    class Fields>
std::size_t
write_header(
    SyncWriteStream& stream,
    serializer< isRequest, Body, Fields >& sr,
    error_code& ec);
  » more...