ACUCOBOL-GT allows you to add color, without reprogramming, to programs that were originally written for black-and-white terminals. You accomplish this by assigning color values to the runtime configuration variable COLOR-MAP. The COLOR-MAP keyword is followed by a single attribute:
High, Low, Reverse, Blink, Underline, Default, Exit, or by a hyphenated combination of attributes:
| High-Reverse
| Low-Reverse
|
| High-Blink
| Low-Blink
|
| High-Reverse-Blink
| Low-Reverse-Blink
|
| High-Underline
| Low-Underline
|
| High-Reverse-Underline
| Low-Reverse-Underline
|
| Reverse-Blink
| Reverse-Underline |
Black, Blue, Green, Cyan, Red, Magenta, Brown, White
The named color becomes the foreground color that is displayed whenever the corresponding attribute is used in a DISPLAY statement. For example, if you want fields that are displayed as low-intensity to appear green, use the following configuration file entry:
COLOR-MAP Low=Green
You can also assign a background color value. It follows the foreground color and is separated from it by a comma. For example, to assign white characters on a blue background for high-intensity fields, you would use the following:
COLOR-MAP High=White,Blue
COLOR-MAP High=Green Low=Red Reverse=Blue
The following points should be noted:
1. The named video attribute is still used by the ACCEPT or DISPLAY. For example, "Reverse=Blue" will result in a reverse-video blue field while "High=Brown" will use high-intensity brown (on some terminals, specifying High=Brown will cause yellow to be generated by any DISPLAY HIGH phrase).
2. If a particular ACCEPT or DISPLAY statement has a COLOR phrase, that phrase will be used instead of the COLOR-MAP attributes in the runtime configuration file. Note, however, that the COLOR-MAP will apply to fields that use the FCOLOR or BCOLOR options of the CONTROL phrase.
3. The attributes HIGH, LOW, and REVERSE are treated in a special manner. If a statement uses more than one of the three, then the attribute/color used will be in this order of preference:
1) REVERSE
2) HIGH
3) LOW
For example, a DISPLAY statement specifying both REVERSE and HIGH will use the color associated with REVERSE.
Also, any one of these settings is used for all applicable cases, except where specifically overridden by another setting. For example:
COLOR-MAP REVERSE=Red LOW-REVERSE=Blue
will use red for all statements that specify REVERSE except for statements that explicitly specify REVERSE,LOW.
In all other cases, the configuration file entry must exactly match the COBOL statement. For example, a configuration file attribute HIGH-REVERSE would not apply to a program statement that included HIGH,REVERSE,UNDERLINE.
Note that compiler options "-Vl" and "-Vh" cause LOW and HIGH respectively to be implied for program statements; create your COLOR-MAP as though LOW or HIGH were explicitly coded in the program.
4. The DEFAULT attribute works a little differently. It is used to assign the initial default colors for the screen. Its effect is the same as having a DISPLAY WINDOW COLOR statement as the first statement of your program.
5. The EXIT attribute determines which colors ACUCOBOL-GT will set when it terminates. These colors are also set when a call is made to the "SYSTEM" library routine. On some machines, such as MS-DOS, these colors are immediately changed by the operating system prompt and thus have no effect.
6. You can assign values to the color map from within a COBOL program through use of the SET ENVIRONMENT verb. You can turn off the color map with the following statement:
SET ENVIRONMENT "COLOR-MAP" TO "OFF"
7. Note that on a XENIX console, if you use the XENIX command "setcolor" to establish a high-intensity background color, you may get unexpected results from ACUCOBOL-GT. This is because the implementation of high-intensity background colors causes XENIX to treat the "blink" bit as a background intensity bit instead. In addition, because ACUCOBOL-GT can select only 8 background colors, all of the background colors used will be high-intensity, including black (which shows up as a light gray).
For these reasons, we recommend that you avoid using a high-intensity background color if you are using the XENIX console. As an alternative, you may create a shell script to run ACUCOBOL-GT. This script could set a low-intensity background color, run ACUCOBOL-GT, and then reset the desired high-intensity background color.