At any time, you can inquire about the current video configuration by passing the _getvideoconfig function a structure of type _videoconfig. The structure contains 11 members, all of which are short integers. They are listed in Table 9.2.
Table 9.2 Members of a _videoconfig Structure
| Member | Description |
| numxpixels | Number of pixels on the x axis |
| numypixels | Number of pixels on the y axis |
| numtextcols | Number of text columns available |
| numtextrows | Number of text rows available |
| numcolors | Number of color indexes |
| bitsperpixel | Number of bits per pixel |
| numvideopages | Number of video pages available |
| mode* | Current video mode |
| adapter* | Active display adapter |
| monitor* | Active display monitor |
| memory | Adapter video memory in kilobytes |
* Possible values for the mode, adapter, and monitor items are listed in the GRAPH.H file.
The _getvideoconfig function initializes these values. Most of the values are self-explanatory. For example, if numxpixels holds 640, the current video mode contains 640 horizontal pixels, numbered 0–639.
The READVC.C example program below illustrates how to initialize and examine a _videoconfig structure:
/* READVC.C — Reads the _videoconfig structure */
#include <graph.h>
#include <stdio.h>
main()
{
struct _videoconfig vc;
_getvideoconfig( &vc );
printf( “Text Rows = %i.\n”, vc.numtextrows );
}
First, the program declares a structure vc of type _videoconfig. Next, it calls _getvideoconfig to initialize the structure. Finally, it prints a member of the structure.