Try OpenEdge Now
skip to main content
Programming Interfaces
Input/Output Processes : Alternate I/O Sources : Understanding input and output

Understanding input and output

When an ABL (Advanced Business Language) procedure gets input from the terminal, it uses an input stream. Similarly, when the procedure sends output to the terminal, it uses an output stream.
Every procedure automatically gets one input stream and one output stream. These are called the unnamed streams. By default, ABL assigns both of these unnamed streams to the terminal, as shown in the following figure.
Figure 23. The unnamed streams
This procedure contains no special syntax about where to get and send data so ABL automatically assigns the input stream and the output stream to the terminal.