code: 9ferno

ref: b502a62da2ec6058923db94f87ecc2d29db2fa77
dir: /man/3/pointer/

.TH POINTER 3
.SH NAME
pointer \- mouse and stylus interface
.SH SYNOPSIS
.B "bind -a #m /dev"
.PP
.B /dev/cursor
.br
.B /dev/pointer
.SH DESCRIPTION
The
.I pointer
device is the interface to input from a mouse, stylus, or some other device
for pointing at positions on a display.
On some platforms, the pointer is associated with a cursor
on the display, that is displayed at the current pointer position.
There often are buttons associated with the pointer, whether on
the pointing device or elsewhere.
For instance, some of the buttons on a PDA might be associated
with the stylus not a keypad, to allow modification of stylus actions
when there are are no buttons on the stylus itself.
In the hosted environment of
.IR emu (1),
the pointer is associated with the host system's own pointing device.
.PP
Reading the
.B pointer
file returns the current pointer position and the state of any buttons associated with the pointer.
The read blocks until the state has changed since the last read.
Each read returns a 49 byte record:
.IP
.BI m "x y buttons msec"
.PP
Each record has the letter
.B m
immedlately followed by four 11-character decimal numbers, each number ended by a blank.
.I X
and
.I y
give the coordinates of the pointer in display coordinates;
the value
.I buttons
has bit
.RI "(1<<" b )
set when button
.I b
is down; and
.I msec
is a time stamp in milliseconds.
.PP
Writing a record of the above form to
.B pointer
moves the displayed cursor to the given
.I x
and
.I y
position;
.I buttons
and
.I msec
are ignored.
.PP
Writing an
.IR image (6)
file to the
.B cursor
file sets the image of the cursor on the display.
Reading
.B cursor
returns the current cursor image, again in
.IR image (6)
format.
.SH SOURCE
.B /emu/port/devpointer.c
.br
.B /os/port/devpointer.c
.SH SEE ALSO
.IR wm (1),
.IR draw-intro (2),
.IR image (6)