.TH "gii_event" 3 "2006-12-30" "libgii-1.0.x" GGI
.SH NAME
\fBgii_event\fR, \fBgii_any_event\fR, \fBgii_event_type\fR, \fBgii_event_mask\fR : LibGII event structures
.SH SYNOPSIS
.nb
.nf
#include <ggi/events.h>

typedef union gii_event {

    uint8_t                 size;

    gii_any_event           any;
    gii_cmd_event           cmd;
    gii_expose_event        expose;
    gii_val_event           val;
    gii_key_event           key;
    gii_pmove_event         pmove;
    gii_pbutton_event       pbutton;
} gii_event;

#define COMMON_DATA  \e
uint8_t   size;           /* size of event in bytes       */\e
uint8_t   type;           /* type of this event           */\e
int16_t   error;          /* error (for replies)          */\e
uint32_t  origin;         /* origin device (etc)          */\e
uint32_t  target;         /* target device (etc)          */\e
struct  timeval time     /* timestamp                    */

typedef struct {

    COMMON_DATA;

} gii_any_event;
.fi

.SH DESCRIPTION
Events are of type \fBgii_event\fR. It is an union of all of the
structures for each specific type of event.
.SH STRUCTURE MEMBERS
All of the event structures contains housekeeping information at the
beginning, as defined by \fBCOMMON_DATA\fR.

Thus, by analyzing the contents of \fBany.type\fR, you can determine what
the given event is, and select the appropriate member of the
\fBgii_event\fR union to access to get at the event

The common fields found in any event structure are:
.TP
size
Specifies the size of the given event (in bytes).

.TP
type
An enumeration of the possible types of LibGII events (see next section).

.TP
error
Mainly there to round things up to a 32-bit boundary, but could
be used to signal an error in a send-reply sequence.

.TP
origin
A device handle: it distinguishes one input device from another.
Other than that there's no real meaning to the number.

.TP
target
Also a device handle, but for distinguishes input devices when
sending events \fBto\fR an input device via \f(CWgiiEventSend(3)\fR.

.TP
time
Indicates when the event in question has been generated. See
\f(CWgettimeofday(2)\fR for more info on the \fBtimeval\fR structure.

.PP
.SH EVENT TYPES
The different types of events are defined as an enumeration of type
\fBgii_event_type\fR. The possible values are:
.IP \(bu 4
\fBevNothing\fR          : event is not valid.
.IP \(bu 4
\fBevCommand\fR          : report command or do action.
.IP \(bu 4
\fBevInformation\fR      : notification of new information.
.IP \(bu 4
\fBevExposure\fR         : exposure event.
.IP \(bu 4
\fBevKeyPress\fR         : a key has been pressed.
.IP \(bu 4
\fBevKeyRelease\fR       : a key has been released.
.IP \(bu 4
\fBevKeyRepeat\fR        : automatically repeated keypress.
.IP \(bu 4
\fBevPtrRelative\fR      : pointer movement reported in relative coordinates.
.IP \(bu 4
\fBevPtrAbsolute\fR      : pointer movement reported in absolute coordinates.
.IP \(bu 4
\fBevPtrButtonPress\fR   : a pointer button has been pressed.
.IP \(bu 4
\fBevPtrButtonRelease\fR : a pointer button has been released.
.IP \(bu 4
\fBevValRelative\fR      : valuator change reported as a relative value.
.IP \(bu 4
\fBevValAbsolute\fR      : valuator change reported as an absolute value.
.PP
.SH EVENT MASKS
\fBgii_event_mask\fR is passed to various event handling functions to
indicate which types of events the program is interested in. The list
below sums the available event masks:
.IP \(bu 4
\fBemCommand\fR        : \fBevCommand\fR
.IP \(bu 4
\fBemInformation\fR    : \fBevInformation\fR
.IP \(bu 4
\fBemExpose\fR         : \fBevExpose\fR
.IP \(bu 4
\fBemKeyPress\fR       : \fBevKeyPress\fR
.IP \(bu 4
\fBemKeyRelease\fR     : \fBevKeyRelease\fR
.IP \(bu 4
\fBemKeyRepeat\fR      : \fBevKeyRepeat\fR
.IP \(bu 4
\fBemKey\fR            : Any of \fBevKeyPress\fR, \fBevKeyRelease\fR or \fBevKeyRepeat\fR
.IP \(bu 4
\fBemPtrRelative\fR    : \fBevPtrRelative\fR
.IP \(bu 4
\fBemPtrAbsolute\fR    : \fBevPtrAbsolute\fR
.IP \(bu 4
\fBemPtrButtonPress\fR : \fBevPtrButtonPress\fR
.IP \(bu 4
\fBemButtonRelease\fR  : \fBevButtonRelease\fR
.IP \(bu 4
\fBemPtrMove\fR        : Any of \fBevPtrRelative\fR or \fBevPtrAbsolute\fR
.IP \(bu 4
\fBemPtrButton\fR      : Any of \fBevPtrButtonPress\fR or \fBevPtrButtonRelease\fR
.IP \(bu 4
\fBemPointer\fR        : All pointer events
.IP \(bu 4
\fBemValRelative\fR    : \fBevValRelative\fR
.IP \(bu 4
\fBemValAbsolute\fR    : \fBevValAbsolute\fR
.IP \(bu 4
\fBemValuator\fR       : Any of \fBevValRelative\fR or \fBevValAbsolute\fR
.IP \(bu 4
\fBemAll\fR            : Any event type
.IP \(bu 4
\fBemNothing\fR        : Matches no event type
.PP
.SH SEE ALSO
\f(CWgii_key_event(3)\fR, \f(CWgii_pmove_event(3)\fR,
\f(CWgii_pbutton_event(3)\fR, \f(CWgii_cmd_event(3)\fR,
\f(CWgii_val_event(3)\fR, \f(CWgii_expose_event(3)\fR