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 NAME     
 |  |  |  | initmouse, readmouse, closemouse, moveto, cursorswitch, getrect,
    drawgetrect, menuhit, setcursor – mouse control 
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 SYNOPSIS     
 |  |  |  | #include <u.h> #include <libc.h>
 #include <draw.h>
 #include <thread.h>
 #include <mouse.h>
 #include <cursor.h>
 Mousectl     *initmouse(char *file, Image *i)
 int          readmouse(Mousectl *mc)
 int          atomouse();
 void         closemouse(Mousectl *mc)
 void         moveto(Mousectl *mc, Point pt)
 void         setcursor(Mousectl *mc, Cursor *c)
 Rectangle    getrect(int but, Mousectl *mc)
 void         drawgetrect(Rectangle r, int up)
 int          menuhit(int but, Mousectl *mc, Menu *menu, Screen *scr)
 
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 DESCRIPTION     
 |  |  |  | These functions access and control a mouse in a multi-threaded
    environment. They use the message-passing Channel interface in
    the threads library (see thread(3)); programs that wish a more
    event-driven, single-threaded approach should use event(3). 
    
    
    The state of the mouse is recorded in a structure, Mouse, defined
    in <mouse.h>: 
 The Point xy records the position of the cursor, buttons the state
    of the buttons (three bits representing, from bit 0 up, the buttons
    from left to right, 0 if the button is released, 1 if it is pressed),
    and msec, a millisecond time stamp. 
    
    
    The routine initmouse returns a structure through which one may
    access the mouse:|  |  |  | typedef struct Mouse Mouse; struct Mouse
 {
 
 };|  |  |  | int       buttons;    /* bit array: LMR=124 */ Point      xy;
 ulong      msec;
 
 | 
 
 | 
 
 The arguments to initmouse are a file naming the device file connected
    to the mouse and an Image (see draw(3)) on which the mouse will
    be visible. Typically the file is nil, which requests the default
    /dev/mouse; and the image is the window in which the program is
    running, held in the variable screen after a call to initdraw.
    
    
    
    Once the Mousectl is set up, mouse motion will be reported by
    messages of type Mouse sent on the Channel Mousectl.c. Typically,
    a message will be sent every time a read of /dev/mouse succeeds,
    which is every time the state of the mouse changes. 
    
    
    When the window is resized, a message is sent on Mousectl.resizec.
    The actual value sent may be discarded; the receipt of the message
    tells the program that it should call getwindow (see graphics(3))
    to reconnect to the window. 
    
    
    Readmouse updates the Mouse structure held in the Mousectl, blocking
    if the state has not changed since the last readmouse or message
    sent on the channel. It calls flushimage (see graphics(3)) before
    blocking, so any buffered graphics requests are displayed. 
    
    
    Closemouse closes the file descriptors associated with the mouse,
    kills the slave processes, and frees the Mousectl structure. 
    
    
    Moveto moves the mouse cursor on the display to the position specified
    by pt. 
    
    
    Setcursor sets the image of the cursor to that specified by c.
    If c is nil, the cursor is set to the default. The format of the
    cursor data is spelled out in <cursor.h> and described in graphics(3).
    
    
    
    Getrect returns the dimensions of a rectangle swept by the user,
    using the mouse, in the manner rio(1) or sam(1) uses to create
    a new window. The but argument specifies which button the user
    must press to sweep the window; any other button press cancels
    the action. The returned rectangle is all zeros if the user cancels.
    
    
    
    Getrect uses successive calls to drawgetrect to maintain the red
    rectangle showing the sweep-in-progress. The rectangle to be drawn
    is specified by rc and the up parameter says whether to draw (1)
    or erase (0) the rectangle. 
    
    
    Menuhit provides a simple menu mechanism. It uses a Menu structure
    defined in <mouse.h>:|  |  |  | typedef struct Mousectl Mousectl; struct Mousectl
 {
 
 };|  |  |  | Mouse; Channel    *c;        /* chan(Mouse)[16] */
 Channel    *resizec;    /* chan(int)[2] */
 char       *file;
 int       mfd;       /* to mouse file */
 int       cfd;       /* to cursor file */
 int       pid;       /* of slave proc */
 Image*     image;      /* of associated window/display */
 
 | 
 
 | 
 
 Menuhit behaves the same as its namesake emenuhit described in
    event(3), with two exceptions. First, it uses a Mousectl to access
    the mouse rather than using the event interface; and second, it
    creates the menu as a true window on the Screen scr (see window(3)),
    permitting the menu to be displayed in parallel with other activities
    on the display.
    If scr is null, menuhit behaves like emenuhit, creating backing
    store for the menu, writing the menu directly on the display,
    and restoring the display when the menu is removed.|  |  |  | typedef struct Menu Menu; struct Menu
 {
 
 };|  |  |  | char       **item; char       *(*gen)(int);
 int       lasthit;
 
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 SOURCE     
 SEE ALSO    
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