The Terminal Manager's keyboard interface has been discussed above. The display interface can also be configured. Its task is to implement, for a particular terminal, those program instructions that specify display attributes. You can accomplish most desired display options by defining, in the terminal database file, the actions that terminal function codes will take. Some other display options can be specified by assigning values to special keywords in the ACUCOBOL-GT runtime configuration file.
The following list describes, in a very simplified way, the overall process from COBOL statement to screen display:
Function Code Generation
1. The COBOL program sends screen output. A sample COBOL statement could be:
DISPLAY data item HIGH
2. The runtime configuration file may specify attributes for the DISPLAY keyword. For example, a configuration file entry for the COBOL statement in 1 above would be:
COLOR-MAP High=Blue
3. The Terminal Manager then maps any COBOL attributes to terminal function codes. For example:
High = HI
Blue = C2
Function Code Interpretation
4. The terminal database file maps the function codes to hardware signals:
HI=\E[0;1m
C2=\E[34m
5. The Terminal Manager then sends the hardware signals to the screen:
\E[0;1m
\E[34m
Final Result
6. The display function is executed, and the data item characters are displayed in blue at high intensity.
This section and section 4.5 describe the runtime configuration file options. Section 4.6 describes the terminal database file function codes and values.