Specifies the widget class containing the extension list to be searched.
Specifies the offset in bytes form the base of the widget class of the
extension field to be searched.
Specifies the name of the class extension to be located.
Specifies the minimum acceptable version of the class extension
required for a match.
Specifies the minimum acceptable length of the class extension record
required for match, or 0.
The list of extension records at the specified offset in the specified
widget_class will be searched for a match on the specified
type, a version greater than or equal to the specified version,
and a record size greater than or equal the specified record_size
if it is nonzero.
returns a pointer to a matching extension record or NULL if no match
is found. The returned extension record is owned by the widget class
and must not be modified or freed by the caller, except possibly to
be modified by the widget class owner.
X Toolkit Intrinsics - C Language Interface Xlib - C Language X Interface