FBIO(4I) Ioctl Requests FBIO(4I)

NAME

fbio - frame buffer control operations

DESCRIPTION

The frame buffers provided with this release support the same general
interface that is defined by <sys/fbio.h>. Each responds to an
FBIOGTYPE ioctl(2) request which returns information in a fbtype
structure.

Each device has an FBTYPE which is used by higher-level software to
determine how to perform graphics functions. Each device is used by
opening it, doing an FBIOGTYPE ioctl(2) to see which frame buffer type
is present, and thereby selecting the appropriate device-management
routines.

FBIOGINFO returns information specific to the GS accelerator.

FBIOSVIDEO and FBIOGVIDEO are general-purpose ioctl(2) requests for
controlling possible video features of frame buffers. These ioctl(2)
requests either set or return the value of a flags integer. At this
point, only the FBVIDEO_ON option is available, controlled by
FBIOSVIDEO. FBIOGVIDEO returns the current video state.

The FBIOSATTR and FBIOGATTR ioctl(2) requests allow access to special
features of newer frame buffers. They use the fbsattr and fbgattr
structures.

Some color frame buffers support the FBIOPUTCMAP and FBIOGETCMAP
ioctl(2) requests, which provide access to the colormap. They use the
fbcmap structure.

Also, some framebuffers with multiple colormaps will either encode the
colormap identifier in the high-order bits of the "index" field in the
fbcmap structure, or use the FBIOPUTCMAPI and FBIOGETCMAPI ioctl(2)
requests.

FBIOVERTICAL is used to wait for the start of the next vertical retrace
period.

FBIOVRTOFFSET Returns the offset to a read-only "vertical retrace page"
for those framebuffers that support it. This vertical retrace page may
be mapped into user space with mmap(2). The first word of the vertical
retrace page (type unsigned int) is a counter that is incremented every
time there is a vertical retrace. The user process can use this
counter in a variety of ways.

FBIOMONINFO returns a mon_info structure which contains information
about the monitor attached to the framebuffer, if available.

FBIOSCURSOR, FBIOGCURSOR, FBIOSCURPOS and FBIOGCURPOS are used to
control the hardware cursor for those framebuffers that have this
feature. FBIOGCURMAX returns the maximum sized cursor supported by the
framebuffer. Attempts to create a cursor larger than this will fail.

Finally FBIOSDEVINFO and FBIOGDEVINFO are used to transfer variable-
length, device-specific information into and out of framebuffers.

SEE ALSO

ioctl(2), mmap(2)

BUGS

The FBIOSATTR and FBIOGATTR ioctl(2) requests are only supported by
frame buffers which emulate older frame buffer types. If a frame
buffer emulates another frame buffer, FBIOGTYPE returns the emulated
type. To get the real type, use FBIOGATTR.

The FBIOGCURPOS ioctl was incorrectly defined in previous operating
systems, and older code running in binary compatibility mode may get
incorrect results.

illumos March 13, 2022 illumos