Introducing typed buffers
Today the most common message exchange formats are JSON and XML, and the most widely used protocol (HTTP) has a special header called content-type to describe the payload type. Tuxedo was created at a time when XML and JSON were not invented yet. At this point, for a C program to carry data, along with metadata describing its format, was an innovative idea. And that is what a typed buffer is: data with a format (type) description.
There are XATMI standard types called STRING and X_OCTET (CARRAY) for zero-terminated C strings and binary data. There are non-standard FML and FML32 types implemented by Tuxedo. We will learn more about them later in this chapter.
However, several typed buffers are not supported by the Python library. I do not suggest using these types in new applications, but if you do use them in existing applications you will have to either update the Python libraries or implement a conversion to the supported types. These types are as...