curs_mouse(3x) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | PORTABILITY | BUGS | SEE ALSO | COLOPHON

curs_mouse(3X)                                            curs_mouse(3X)

NAME         top

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

SYNOPSIS         top

       #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         top

       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.

       •   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.

       •   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).

       •   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 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         top

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

          •   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         top

       These calls were designed for ncurses(3X), 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:

       •   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:

          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(3X), 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(3X) (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         top

       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         top

       curses(3X), curs_inopts(3X), curs_kernel(3X), curs_slk(3X),
       curs_variables(3X).

COLOPHON         top

       This page is part of the ncurses (new curses) project.
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                                                          curs_mouse(3X)