Access to a stream (Server)
The DataBlade® API provides a stream I/O interface, which enables you to use the same function calls to access different objects. Stream is a generic term for an object that can be written to or read from.
A stream has the following information associated with it:
- The stream data, to which the stream provides access
- The stream seek position, which identifies where
the next read or write operation starts in the stream
When you first open a stream, its seek position is at byte zero.
- The stream descriptor, which contains information about the stream
To provide access to a stream from within a C UDR, the DataBlade®
API has
the MI_STREAM data type structure for stream descriptors. An MI_STREAM structure
contains information about a stream on a particular object. The following
table summarizes the memory operations for a stream descriptor.
| Memory duration | Memory operation | Function name |
|---|---|---|
| Current® memory duration | Constructor | mi_stream_open_fio(), mi_stream_open_mi_lvarchar(),
mi_stream_open_str() Other, user-defined stream-open functions |
| Current® memory duration | Destructor | mi_stream_close() |