osf1 man page for xtoffsetof

XtOffset(3Xt)															     XtOffset(3Xt)

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

SYNOPSIS
       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
       Specifies  a  fixed-size array.	Specifies the name of the field for which to calculate the byte offset.  Specifies a type that is declared
       as a pointer to the structure.  Specifies a type that is declared as a structure.

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 member from 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

																     XtOffset(3Xt)