curs_mouse 3x 2023-10-14 ncurses 6.4 Library calls

curs_mouse(3x)                   Library calls                  curs_mouse(3x)




NAME

       has_mouse,  getmouse,  ungetmouse,  mousemask,  wenclose,  mouse_trafo,
       wmouse_trafo, mouseinterval - get mouse events in 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(3x).
       Mouse  events  are  represented  by  KEY_MOUSE pseudo-key values in the
       wgetch(3x) input stream.


mousemask

       To make mouse events visible, use the mousemask  function.   This  sets
       the  mouse  events  to  be  reported.   By default, no mouse events are
       reported.

       o   The function returns an updated copy of newmask to  indicate  which
           of the specified mouse events can be reported.

           If the screen has not been initialized, or if the terminal does not
           support mouse-events, this function returns 0.

       o   If oldmask is non-NULL, this function fills the indicated  location
           with the previous value of the current screen'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 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.


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 coordinates.


wenclose

       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.


wmouse_trafo

       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(3x) calls, for example).

       o   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.

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

       o   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.

       o   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
           successful.


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
       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.


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 input-
       loop termination.


RETURN VALUE

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

          getmouse
               returns an error.

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

          o   It returns an error if a mouse event was detected which did  not
              match the current mousemask.

          o   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,  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(1).  It is
       mentioned in a few places, but with no supporting documentation:

       o   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);

       o   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

       o   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:

          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, these calls are implemented using either xterm's  built-
       in mouse-tracking API or platform-specific drivers including

          o   Alessandro Rubini's gpm server

          o   FreeBSD sysmouse

          o   OS/2 EMX

       If you are using an unsupported configuration, mouse events will not be
       visible to ncurses (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 from xterm are not ignored in cooked  mode  if  they  have
       been  enabled  by  mousemask.  Instead, the xterm mouse report sequence
       appears in the string read.

       Mouse event reports from xterm are not detected correctly in  a  window
       with  keypad application mode disabled, since they are interpreted as a
       variety of function key.  Set the the  terminal's  terminfo  capability
       kmous  to  "\E[M"  (the  beginning of the response from xterm for mouse
       clicks).   Other  values  of  kmous  are  permitted  under   the   same
       assumption, that is, the report begins with that sequence.

       Because there are no standard response sequences that serve to identify
       terminals supporting the xterm mouse protocol, ncurses assumes that  if
       kmous is defined in the terminal description, or if the terminal type's
       primary name or aliases contain the string "xterm", then  the  terminal
       may send mouse events.  The kmous capability is checked first, allowing
       use of newer xterm mouse protocols such as its private mode 1006.


SEE ALSO

       curses(3x),     curs_inopts(3x),     curs_kernel(3x),     curs_slk(3x),
       curs_variables(3x)



ncurses 6.4                       2023-10-14                    curs_mouse(3x)