curs_mouse()

NAME

getmouse(), ungetmouse(), mousemask() - mouse interface through curses

SYNOPSIS

#include <curses.h>

typedef unsigned long mmask_t;
typedef struct { short id; /* ID to distinguish multiple devices */ int x, y, z; /* event coordinates */ mmask_t bstate; /* button state bits */ } MEVENT;
int getmouse(MEVENT *event); int ungetmouse(MEVENT *event); mmask_t mousemask(mmask_t newmask, mmask_t *oldmask); bool wenclose(WINDOW *win, int y, int x) int mouseinterval(int erval)

DESCRIPTION

These functions provide an interface to mouse events from ncurses Mouse events are represented by KEY_MOUSE pseudo-key values in the wgetch(3) input stream.

To make mouse events visible, use the mousemask(3) function. This will set the mouse events to be reported. By default, no mouse events are reported. The function will return a mask to indicate which of the specified mouse events can be reported; on complete failure it returns 0. If oldmask is non-NULL, this function fills the indicated location with the previous value of the given window's mouse event mask.

As a side effect, setting a zero mousemask may turn off the mouse pointer; setting a nonzero mask may turn it on. Whether this happens is device-dependent.

Here are the mouse event type masks:

Name Description
BUTTON1_PRESSED mouse button 1 down
BUTTON1_RELEASED mouse button 1 up
BUTTON1_CLICKED mouse button 1 clicked
BUTTON1_DOUBLE_CLICKED mouse button 1 double clicked
BUTTON1_TRIPLE_CLICKED mouse button 1 triple clicked
BUTTON2_PRESSED mouse button 2 down
BUTTON2_RELEASED mouse button 2 up
BUTTON2_CLICKED mouse button 2 clicked
BUTTON2_DOUBLE_CLICKED mouse button 2 double clicked
BUTTON2_TRIPLE_CLICKED mouse button 2 triple clicked
BUTTON3_PRESSED mouse button 3 down
BUTTON3_RELEASED mouse button 3 up
BUTTON3_CLICKED mouse button 3 clicked
BUTTON3_DOUBLE_CLICKED mouse button 3 double clicked
BUTTON3_TRIPLE_CLICKED mouse button 3 triple clicked
BUTTON4_PRESSED mouse button 4 down
BUTTON4_RELEASED mouse button 4 up
BUTTON4_CLICKED mouse button 4 clicked
BUTTON4_DOUBLE_CLICKED mouse button 4 double clicked
BUTTON4_TRIPLE_CLICKED mouse button 4 triple clicked
BUTTON_SHIFT shift was down during button state change
BUTTON_CTRL control was down during button state change
BUTTON_ALT alt was down during button state change
ALL_MOUSE_EVENTS report all button state changes
REPORT_MOUSE_POSITION report mouse movement

Once a class of mouse events have been made visible in a window, calling the wgetch(3) function on that window may return KEY_MOUSE as an indicator that a mouse event has been queued. To read the event data and pop the event off the queue, call getmouse(3). This function will return OK if a mouse event is actually visible in the given window, ERR otherwise. When getmouse(3) returns OK, the data deposited as y and x in the event structure coordinates will be screen-relative character-cell coordinates. The returned state mask will have exactly one bit set to indicate the event type.

The ungetmouse(3) function behaves analogously to ungetch(3). It pushes a KEY_MOUSE event onto the input queue, and associates with that event the given state data and screen-relative character-cell coordinates.

The wenclose() function tests whether a given pair of screen-relative character-cell coordinates is enclosed by a given window, returning TRUE if it is and FALSE otherwise. It is useful for determining what subset of the screen windows enclose the location of a mouse event.

The mouseinterval() function sets the maximum time (in thousands of a second) that can elapse between press and release events in order for them to be recognized as a click. This function returns the previous interval value. The default is one fifth of a second.

Note that mouse events will be ignored when input is in cooked mode, and will cause an error beep when cooked mode is being simulated in a window by a function such as getstr(3) that expects a linefeed for input-loop termination.

RETURN VALUE

All routines return the integer ERR upon failure or OK upon successful completion.

PORTABILITY

These calls were designed for ncurses and are not found in SVr4 curses, 4.4BSD curses, or any other previous version of curses.

The feature macro NCURSES_MOUSE_VERSION is provided so the preprocessor can be used to test whether these features are present (its value is 1). NOTE: THIS INTERFACE IS EXPERIMENTAL AND IS SUBJECT TO CHANGE WITHOUT NOTICE! If the interface is changed, the value of NCURSES_MOUSE_VERSION will be incremented.

These functions are not provided under the Interix subsystem. NCURSES_MOUSE_VERSION is set to 0. This reference page is provided for information value only.

The order of the MEVENT structure members is not guaranteed. Additional fields may be added to the structure in the future.

Under ncurses these calls are implemented using either xterm(1)'s built-in mouse-tracking API or Alessandro Rubini's gpm server. If you are using something other than xterm(1) there is no gpm daemon running on your machine, mouse events will not be visible to ncurses (and the wmousemask(3) function will always return 0).

The z member in the event structure is not presently used. It is intended for use with touchscreens (which may be pressure-sensitive) or with 3D-mice/trackballs/power gloves.

BUGS

Mouse events under xterm(1) will not in fact be ignored during cooked mode, if they have been enabled by wmousemask(). Instead, the xterm mouse report sequence will appear in the string read.

Mouse events under xterm will not be detected correctly in a window with its keypad bit off.

SEE ALSO

curses(3)