MOUSE(3)
NAME
mouse, cursor − kernel mouse interface
SYNOPSIS
bind -a #m /dev
/dev/mouse
/dev/mousein
/dev/mousectl
/dev/cursor
DESCRIPTION
The mouse device provides an interface to the mouse. There is also a cursor associated with the screen; it is always displayed at the current mouse position.
Reading the mouse file returns the mouse status: its position and button state. The read blocks until the state has changed since the last read. The read returns 49 bytes: the letter m followed by four decimal strings, each 11 characters wide followed by a blank: x and y, coordinates of the mouse position in the screen image; buttons, a bitmask with the 1, 2, and 4 bits set when the mouse’s left, middle, and right buttons, respectively, are down; and msec, a time stamp, in units of milliseconds.
Writing the mouse file, in the same format, causes the mouse cursor to move to the position specified by the x and y coordinates of the message. The buttons and msec fields are ignored and may be omitted.
Writes to the mousein file are processed as if they were generated by the mouse hardware itself, as extra mouse events to be processed and passed back via the mouse file. The mousein file, which is exclusive-use, is intended for controlling devices, such as USB mice, that are managed by user-level software. Each event should consist of the letter m followed by x, y, and buttons as space-separated decimal numbers.
Writing to the mousectl file configures and controls the mouse. The messages are:
serial n sets serial port n to be the mouse port.
ps2 sets the PS2 port to be the mouse port.
intellimouse uses the wheel on a Microsoft Intellimouse as the middle button.
ps2intellimouse
is equivalent to a write of ps2 followed by a write of intellimouse.
accelerated turns on mouse acceleration.
linear turns off mouse acceleration
res n sets mouse resolution to a setting between 0 and 3 inclusive.
swap swaps the left and right buttons on the mouse.
buttonmap xyz numbers the left, middle, and right mouse buttons x, y, and z, respectively. If xyz is omitted, the default map, 123, is used. Thus in the default state writing buttonmap 321 swaps left and right buttons and writing buttonmap 123 or just buttonmap restores their usual meaning. Note that buttonmap messages are idempotent, unlike swap.
reset clears the mouse to its default state.
Not all mice interpret all messages; with some devices, some of the messages may be no-ops.
Cursors are described in graphics(2). When read or written from or to the cursor file, they are represented in a 72-byte binary format. The first and second four bytes are little endian 32-bit numbers specifying the x and y coordinates of the cursor offset; the next 32 bytes are the clr bitmask, and the last 32 bytes the set bitmask.
Reading from the cursor file returns the current cursor information. Writing to the cursor file sets the current cursor information. A write of fewer than 72 bytes sets the cursor to the default, an arrow.
The mouse and cursor files are multiplexed by rio(1) to give the illusion of a private mouse to each of its clients. The semantics are otherwise the same except that notification of a window resize is passed to the application using a mouse message beginning with r rather than m; see rio(4) for details.
SOURCE
/sys/src/9/port/devmouse.c
SEE ALSO
BUGS
The cursor format is big endian while the rest of the graphics interface is little endian.
The mousein file is disabled.
Plan 9 — July 29, 2000