AP(4)

NAME
xf86 - XFree86 Framebuffer aperture driver

DESCRIPTION
This module was written to help work around the security feature of the OS that prevents read/write access to /dev/mem.

XFree86 can take advantage of having direct access to video memory (especially with VLB and PCI cards) and even requires it for the P9000 server.

This driver works like the standard /dev/mem driver. It just allows mapping of the VGA framebuffer even if kernel security level is > 0. The driver only implements the open(2), close(2), mmap(2) calls. In order not to defeat kernel security, only one open() at a time is allowed and only a process with effective user id of 0 can perform it. So while you're running XFree86, no other process will be allowed to open /dev/xf86

FILES
/dev/xf86

SEE ALSO
mem(4), kmem(4)

HISTORY
This work is heavily inspired from the Solaris x86 aperture driver by Doug Anson (danson@lgc.com) and David Holland (davidh@use.com).