vga_getgraphmem(3) returns the address of the VGA memory


#include <vga.h>

unsigned char *graph_mem; /* This declaration is already in vga.h */

unsigned char *vga_getgraphmem(void);


returns a pointer to the 64K VGA frame buffer window. vga_setpage(3), vga_setreadpage(3) and vga_setwritepage(3) allow to select which page of the VGA memory shows up at this position. vga_setlinearaddressing(3) maps all VGA memory at a consecutive memory area (if the hardware supports it). In this mode, vga_getgraphmem() will return the location of this area too. You can also access the global variable graph_mem, which will also contain this address.

Most demos, esp. vgatest(6) show the simple direct use of this function to access screen memory.


This manual page was edited by Michael Weller <[email protected]>. The exact source of the referenced function as well as of the original documentation is unknown.

It is very likely that both are at least to some extent are due to Harm Hanemaayer <[email protected]>.

Occasionally this might be wrong. I hereby asked to be excused by the original author and will happily accept any additions or corrections to this first version of the svgalib manual.