NAME¶

SYNOPSIS¶

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;

bool has_mouse(void);
int getmouse(MEVENT *event);
int ungetmouse(MEVENT *event);
mmask_t mousemask(mmask_t newmask, mmask_t *oldmask);
bool wenclose(const WINDOW *win, int y, int x);
bool mouse_trafo(int* pY, int* pX, bool to_screen);
bool wmouse_trafo(const WINDOW* win, int* pY, int* pX,
bool to_screen);
int mouseinterval(int erval);

DESCRIPTION¶

RETURN VALUE¶

mousemask returns the mask of reportable events.

mouseinterval returns the previous interval value, unless the terminal was not initialized. In that case, it returns the maximum interval value (166).

wenclose and wmouse_trafo are boolean functions returning TRUE or FALSE depending on their test result.

PORTABILITY¶

SVr4 curses had support for the mouse in a variant of xterm. It is mentioned in a few places, but with no supporting documentation:

• the “libcurses” manual page lists functions for this feature which are prototyped in curses.h:

  
  

  extern int mouse_set(long int);
  extern int mouse_on(long int);
  extern int mouse_off(long int);
  extern int request_mouse_pos(void);
  extern int map_button(unsigned long);
  extern void wmouse_position(WINDOW *, int *, int *);
  extern unsigned long getmouse(void), getbmap(void);
      

  
  
• the “terminfo” manual page lists capabilities for the feature

  
  

  buttons           btns    BT       Number of buttons on the mouse
  get_mouse         getm    Gm       Curses should get button events
  key_mouse         kmous   Km       0631, Mouse event has occurred
  mouse_info        minfo   Mi       Mouse status information
  req_mouse_pos     reqmp   RQ       Request mouse position report
      

  
  
• the interface made assumptions (as does ncurses) about the escape sequences sent to and received from the terminal.

For instance the SVr4 curses library used the get_mouse capability to tell the terminal which mouse button events it should send, passing the mouse-button bit-mask to the terminal. Also, it could ask the terminal where the mouse was using the req_mouse_pos capability.

Those features required a terminal which had been modified to work with curses. They were not part of the X Consortium's xterm.

When developing the xterm mouse support for ncurses in September 1995, Eric Raymond was uninterested in using the same interface due to its lack of documentation. Later, in 1998, Mark Hesseling provided support in PDCurses 2.3 using the SVr4 interface. PDCurses, however, does not use video terminals, making it unnecessary to be concerned about compatibility with the escape sequences.

The feature macro NCURSES_MOUSE_VERSION is provided so the preprocessor can be used to test whether these features are present. If the interface is changed, the value of NCURSES_MOUSE_VERSION will be incremented. These values for NCURSES_MOUSE_VERSION may be specified when configuring ncurses:

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

Under ncurses(3NCURSES), these calls are implemented using either xterm's built-in mouse-tracking API or platform-specific drivers including

If you are using an unsupported configuration, mouse events will not be visible to ncurses(3NCURSES) (and the mousemask function will always return 0).

If the terminfo entry contains a XM string, this is used in the xterm mouse driver to control the way the terminal is initialized for mouse operation. The default, if XM is not found, corresponds to private mode 1000 of xterm:

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

The ALL_MOUSE_EVENTS class does not include REPORT_MOUSE_POSITION. They are distinct. For example, in xterm, wheel/scrolling mice send position reports as a sequence of presses of buttons 4 or 5 without matching button-releases.

BUGS¶

Mouse events under xterm will not be detected correctly in a window with its keypad bit off, since they are interpreted as a variety of function key. Your terminfo description should have kmous set to "\E[M" (the beginning of the response from xterm for mouse clicks). Other values for kmous are permitted, but under the same assumption, i.e., it is the beginning of the response.

Because there are no standard terminal responses that would serve to identify terminals which support the xterm mouse protocol, ncurses assumes that if your $TERM environment variable contains "xterm", or kmous is defined in the terminal description, then the terminal may send mouse events.

SEE ALSO¶