has_mouse, getmouse, ungetmouse, mousemask, wenclose, mouse_trafo,
   wmouse_trafo, mouseinterval - mouse interface through curses


   #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);


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

   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
   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.

   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

   Once a class of mouse events has been made visible in a window, calling
   the wgetch 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.  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.

   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 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 wmouse_trafo function transforms a given pair of  coordinates  from
   stdscr-relative coordinates to coordinates 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 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  converted  to  stdscr-relative
       coordinates if the window win encloses this point.   In  this  case
       the function returns TRUE.

   *   If  one  of  the  parameters is NULL or the point is not inside the
       window, FALSE is returned.  The  referenced  coordinates  are  only
       replaced  by  the  converted  coordinates if the transformation was

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

   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
   resolution.  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.

   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 input-
   loop termination.


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

           returns an error.

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

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

           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.


   These  calls  were designed for ncurses(3NCURSES), 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.  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:

      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

      *   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:


   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.


   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  your $TERM environment variable contains "xterm", or
   kmous is defined in the terminal description,  then  the  terminal  may
   send mouse events.


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



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