'\" t
.\"     Title: xquerydevicestate
.\"    Author: [FIXME: author] [see http://docbook.sf.net/el/author]
.\" Generator: DocBook XSL Stylesheets v1.76.1 <http://docbook.sf.net/>
.\"      Date: 03/18/2011
.\"    Manual: \ \&
.\"    Source: \ \&
.\"  Language: English
.\"
.TH "XQUERYDEVICESTATE" "libmansuffix" "03/18/2011" "\ \&" "\ \&"
.\" -----------------------------------------------------------------
.\" * Define some portability stuff
.\" -----------------------------------------------------------------
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.\" http://bugs.debian.org/507673
.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.ie \n(.g .ds Aq \(aq
.el       .ds Aq '
.\" -----------------------------------------------------------------
.\" * set default formatting
.\" -----------------------------------------------------------------
.\" disable hyphenation
.nh
.\" disable justification (adjust text to left margin only)
.ad l
.\" -----------------------------------------------------------------
.\" * MAIN CONTENT STARTS HERE *
.\" -----------------------------------------------------------------
.SH "NAME"
XQueryDeviceState \- query the state of an extension input device\&.
.SH "SYNOPSIS"
.sp
.nf
#include <X11/extensions/XInput\&.h>
.fi
.sp
.nf
XDeviceState* XQueryDeviceState( Display *display,
                                 XDevice *device);
.fi
.sp
.nf
display
       Specifies the connection to the X server\&.
.fi
.sp
.nf
device
       Specifies the device whose state is to be queried\&.
.fi
.SH "DESCRIPTION"
.sp
.if n \{\
.RS 4
.\}
.nf
The XQueryDeviceState request queries the state of an input
device\&. The current state of keys and buttons (up or down), and
valuators (current value) on the device is reported by this
request\&. Each key or button is represented by a bit in the
XDeviceState structure that is returned\&. Valuators on the
device report 0 if they are reporting relative information, and
the current value if they are reporting absolute information\&.
.fi
.if n \{\
.RE
.\}
.sp
.if n \{\
.RS 4
.\}
.nf
XQueryDeviceState can generate a BadDevice error\&.
.fi
.if n \{\
.RE
.\}
.sp
.if n \{\
.RS 4
.\}
.nf
Structures:
.fi
.if n \{\
.RE
.\}
.sp
.if n \{\
.RS 4
.\}
.nf
The XDeviceState structure contains:
.fi
.if n \{\
.RE
.\}
.sp
.if n \{\
.RS 4
.\}
.nf
typedef struct {
    XID device_id;
    int num_classes;
    XInputClass *data;
} XDeviceState;
.fi
.if n \{\
.RE
.\}
.sp
.if n \{\
.RS 4
.\}
.nf
The XValuatorState structure contains:
.fi
.if n \{\
.RE
.\}
.sp
.if n \{\
.RS 4
.\}
.nf
typedef struct {
    unsigned char class;
    unsigned char length;
    unsigned char num_valuators;
    unsigned char mode;
    int *valuators;
} XValuatorState;
.fi
.if n \{\
.RE
.\}
.sp
.if n \{\
.RS 4
.\}
.nf
The XKeyState structure contains:
.fi
.if n \{\
.RE
.\}
.sp
.if n \{\
.RS 4
.\}
.nf
typedef struct {
    unsigned char class;
    unsigned char length;
    short     num_keys;
    char keys[32];
} XKeyState;
.fi
.if n \{\
.RE
.\}
.sp
.if n \{\
.RS 4
.\}
.nf
The XButtonState structure contains:
.fi
.if n \{\
.RE
.\}
.sp
.if n \{\
.RS 4
.\}
.nf
typedef struct {
    unsigned char class;
    unsigned char length;
    short     num_buttons;
    char buttons[32];
} XButtonState;
.fi
.if n \{\
.RE
.\}
.SH "DIAGNOSTICS"
.sp
.if n \{\
.RS 4
.\}
.nf
BadDevice
       An invalid device was specified\&. The specified device
       does not exist or has not been opened by this client via
       XOpenInputDevice\&. This error may also occur if some
       other client has caused the specified device to become
       the X keyboard or X pointer device via the
       XChangeKeyboardDevice or XChangePointerDevice requests\&.
.fi
.if n \{\
.RE
.\}