> The VGA BIOS is not reentrant, so you'd have to disable interrupts while
> calling it, which would play havoc with the process granularity. Also, it's
> not much help on EGA or CGA systems.
Well, only one process should be calling the VGA BIOS at a time anyway
(probably accessing it through a device driver that allows only 1 process
to open the device at a time).
/dev/fb linked to /dev/vga, /dev/cga, /dev/ega, or /dev/hgc anyone? Too bad
ELKS doesn't support memory mapped files. If you've got the device opened
sucessfully, feel freee to play with video memory and video BIOS calls. If you
don't, don't make video BIOS calls or touch video memory. (The video BIOS
calls should probably be made with ioctls rather than directly. read() and
write() support would get big images to and from the screen quickly. People
who want to see how slow their computers can go can use lseek() for pixel
adressing.) And if ELKS (286) ever gets memory mapped files... memory
mapped frame buffers are nice.
Eric
