NAME

       XGetDeviceProperty, XChangeDeviceProperty, XDeleteDeviceProperty - Get, change or delete a
       device's property.

SYNOPSIS

       #include <X11/extensions/XInput.h>

       int XGetDeviceProperty( Display *display,
                               XDevice *device,
                               Atom property,
                               long offset,
                               long length,
                               Bool delete,
                               Atom req_type,
                               Atom *actual_type_return,
                               int *actual_format_return,
                               unsigned long *nitems_return,
                               unsigned long *bytes_after_return,
                               unsigned char **prop_return)

       void XChangeDeviceProperty( Display *display,
                                   XDevice *device,
                                   Atom property,
                                   Atom type,
                                   int format,
                                   int mode,
                                   const char *data,
                                   int nelements)

       void XDeleteDeviceProperty( Display *display,
                                   XDevice *device,
                                   Atom property)

       actual_type_return
              Returns an atom identifier that defines the actual type
              of the property.

       actual_format_return
              Returns the actual format of the property.

       bytes_after_return
              Returns the number of bytes remaining to be read in the
              property if a partial read was performed.

       data
              Specifies the property data.

       delete
              Specifies a Boolean value that determines whether the
              property is deleted.

       display
              Specifies the connection to the X server.

       device
              The device to grab.

       format
              Specifies whether the data should be viewed as a list of
              8-bit, 16-bit, or 32-bit quantities. Possible values are
              8, 16, and 32. This information allows the X server to
              correctly perform byte-swap operations as necessary. If
              the format is 16-bit or 32-bit, you must explicitly cast
              the data pointer to an (unsigned char*) in the call to
              XChangeDeviceProperty.

       length
              Specifies the length in 32-bit multiplies of the data to
              be retrieved.

       mode
              Specifies the mode of operation. You can pass
              PropModeReplace, PropModePrepend, or PropModeAppend.

       nelements
              Specifies the number of elements in data.

       nitems_return
              Returns the actual number of 8-bit, 16-bit, or 32-bit
              items stored in the prop_return array.

       num_values
              Specifies the number of elements in the values list.

       offset
              Specifies the offset in the specified property (in
              32-bit quantities) where the data is to be retrieved.

       property
              Specifies the property to modify or query.

       prop_return
              Returns the data in the specified format. If the
              returned format is 8, the returned data is represented
              as a char array. If the returned format is 16, the
              returned data is represented as an array of short int
              type and should be cast to that type to obtain the
              elements. If the returned format is 32, the property
              data will be stored as an array of longs (which in a
              64-bit application will be 64-bit values that are padded
              in the upper 4 bytes).

       req_type
              Specifies the atom identifier associated with the
              property type or AnyPropertyType.

DESCRIPTION

       The XGetDeviceProperty function returns the actual type of the property; the actual format
       of the property; the number of 8-bit, 16-bit, or 32-bit items transferred; the number of
       bytes remaining to be read in the property; and a pointer to the data actually returned.
       For a detailed description of this function, see the man page to XGetWindowProperty.

       The XChangeDeviceProperty function alters the property for the specified device and causes
       the server to generate a XPropertyNotifyEvent event on that device. For a detailed
       description of this function, see the man page to XChangeProperty.

       The XDeleteDeviceProperty function deletes the specified device property. Note that a
       client cannot delete a property created by a driver or the server. Attempting to do so
       will result in a BadAtom error.

       XGetDeviceProperty can generate a BadAtom, BadDevice error.

       XChangeDeviceProperty can generate a BadDevice, a BadMatch, a BadAtom, and a BadValue
       error.

       XDeleteDeviceProperty can generate a BadDevice, and a BadAtom error.

DIAGNOSIS

           BadAtom
                  A value does not describe a valid named identifier or
                  the client attempted to remove a driver-allocated
                  property.

           BadDevice
                  An invalid device was specified. The device does not
                  exist.

SEE ALSO

           XListDeviceProperties(3)

                                            09/15/2021                      XGETDEVICEPROPERTY(3)