Linux Certif

Toute la documentation sur la certification Linux LPI

XDeleteDeviceProperty

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,
                         Bool pending,
                         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.
 

 pending
        Specifies whether to retrieve the pending state of the
        property or the current state.
 

 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)