Provided by: ncurses-doc_6.3-2ubuntu0.1_all bug

NAME

       has_mouse, getmouse, ungetmouse, mousemask, wenclose, mouse_trafo, wmouse_trafo, mouseinterval - 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;

       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

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

   mousemask
       To make mouse events visible, use the mousemask 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 spec‐
       ified mouse events can be reported; on complete failure it returns 0.  If oldmask is non-NULL, this func‐
       tion 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.

   Mouse events
       Here are the mouse event type masks which may be defined:

       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
       ─────────────────────────────────────────────────────────────────────
       BUTTON5_PRESSED          mouse button 5 down
       BUTTON5_RELEASED         mouse button 5 up
       BUTTON5_CLICKED          mouse button 5 clicked
       BUTTON5_DOUBLE_CLICKED   mouse button 5 double clicked
       BUTTON5_TRIPLE_CLICKED   mouse button 5 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
       ─────────────────────────────────────────────────────────────────────

   getmouse
       Once a class of mouse events has been made visible in a window, calling the wgetch function on that  win‐
       dow  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.  This function will return OK if a mouse  event  is  actually
       visible  in  the given window, ERR otherwise.  When getmouse 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 corresponding data in the queue is
       marked invalid.  A subsequent call to getmouse will retrieve the next older item from the queue.

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

   wenclose
       The wenclose function tests whether a given pair of screen-relative  character-cell  coordinates  is  en‐
       closed 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.

   wmouse_trafo
       The  wmouse_trafo function transforms a given pair of coordinates from stdscr-relative coordinates to co‐
       ordinates relative to the given window or vice versa.  The resulting stdscr-relative coordinates are  not
       always identical to window-relative coordinates due to the mechanism to reserve lines on top or bottom of
       the screen for other purposes (see the ripoffline and slk_init(3X) calls, for example).

       •   If  the parameter to_screen is TRUE, the pointers pY, pX must reference the coordinates of a location
           inside the window win.  They are converted to window-relative coordinates and  returned  through  the
           pointers.  If the conversion was successful, the function returns TRUE.

       •   If one of the parameters was NULL or the location is not inside the window, FALSE is returned.

       •   If to_screen is FALSE, the pointers pY, pX must reference window-relative coordinates.  They are con‐
           verted  to stdscr-relative coordinates if the window win encloses this point.  In this case the func‐
           tion returns TRUE.

       •   If one of the parameters is NULL or the point is not inside the window, FALSE is returned.  The  ref‐
           erenced coordinates are only replaced by the converted coordinates if the transformation was success‐
           ful.

   mouse_trafo
       The mouse_trafo function performs the same translation as wmouse_trafo, using stdscr for win.

   mouseinterval
       The mouseinterval function sets the maximum time (in thousands of a second) that can elapse between press
       and  release  events for them to be recognized as a click.  Use mouseinterval(0) to disable click resolu‐
       tion.  This function returns the previous interval value.  Use mouseinterval(-1) to obtain  the  interval
       without altering it.  The default is one sixth of a second.

   has_mouse
       The has_mouse function returns TRUE if the mouse driver has been successfully initialized.

       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 that expects a linefeed  for  in‐
       put-loop termination.

RETURN VALUE

       getmouse and ungetmouse return the integer ERR upon failure or OK upon successful completion:

          getmouse
               returns an error.

          •   If no mouse driver was initialized, or if the mask parameter is zero,

          •   It also returns an error if no more events remain in the queue.

          ungetmouse
               returns an error if the FIFO is full.

       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

       These calls were designed for ncurses(3NCURSES), and are not found in SVr4 curses, 4.4BSD curses, or  any
       other previous version of curses.

       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  sup‐
       port  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 increment‐
       ed.  These values for NCURSES_MOUSE_VERSION may be specified when configuring ncurses:

          1  has definitions for reserved events.  The mask uses 28 bits.

          2  adds definitions for button 5, removes the definitions for reserved events.  The mask uses 29 bits.

       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

          •   Alessandro Rubini's gpm server

          •   FreeBSD sysmouse

          •   OS/2 EMX

       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:

          \E[?1000%?%p1%{1}%=%th%el%;

       The mouse driver also recognizes a newer xterm private mode 1006, e.g.,

          \E[?1006;1000%?%p1%{1}%=%th%el%;

       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 in fact be ignored during cooked mode, if they  have  been  enabled  by
       mousemask.  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, 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 kmous is defined in the terminal  description,  or  if  the
       terminal  description's  primary  name  or aliases contain the string “xterm”, then the terminal may send
       mouse events.  The kmous capability is checked first, allowing the use of  newer  xterm  mouse  protocols
       such as xterm's private mode 1006.

SEE ALSO

       ncurses(3NCURSES), kernel(3NCURSES), slk(3NCURSES), curses_variables(3NCURSES).

                                                                                                 mouse(3NCURSES)