XtOffset(3Xt)

NAME
       XtOffset, XtOffsetOf, XtNumber - determine the byte offset
       or number of array elements

SYNTAX
       Cardinal XtOffset(pointer_type, field_name)
             Type pointer_type;
             Field field_name;

       Cardinal XtOffsetOf(structure_type, field_name)
             Type structure_type;
             Field field_name;

       Cardinal XtNumber(array)
             ArrayVariable array;

ARGUMENTS
       array     Specifies a fixed-size array.

       field_name
                 Specifies the name of the field for which to
                 calculate the byte offset.

       pointer_type
                 Specifies a type that is declared as a pointer
                 to the structure.

       structure_type
                 Specifies a type that is declared as a struc-
                 ture.

DESCRIPTION
       The XtOffset macro is usually used to determine the offset
       of various resource fields from the beginning of a widget
       and can be used at compile time in static initializations.

       The XtOffsetOf macro expands to a constant expression that
       gives the offset in bytes to the specified structure mem-
       ber rom the beginning of the structure.  It is normally
       used to statically initialize resource lists and is more
       portable than XtOffset, which serves the same function.

       The XtNumber macro returns the number of elements in the
       specified argument lists, resources lists, and other
       counted arrays.

SEE ALSO
       XtGetResourceList(3Xt) XtSetArg(3Xt) 
       X Toolkit Intrinsics - C Language Interface
       Xlib - C Language X Interface