The CALLING function is a relationship function. It finds
    occurrences with the CALLING relationship between them. For
    example, if routine A is calling routine B, then these two
    occurrences are in a CALLING relationship. In its most common
    form, the function format is as follows:

    CALLING( <callee>, <caller>, DEPTH={<number> | ALL} )

    In this format, <callee> and <caller> can be any legal query
    expression and <number> is a positive integer. A typical use of
    the function is to find those routines which are calling some
    specified routine call. For example,

      FIND CALLING( abc, *, DEPTH=ALL )

    This query finds the full call tree above ABC, where ABC is some
    routine in the SCA database. In other words, find all the routines
    that are directly or indirectly calling ABC.

    The CALLING function provides the power to return the exact call
    tree of interest. The full format is:

    CALLING ( [ END=<callee> ],
              [ BEGIN=<caller> ],
              [ DEPTH={<number> | ALL} ],
              [ RESULT=RESULT_KEYWORD ],
              [ TRACE=query_expression ] )

    In the previous format, <callee> and <caller> is any legal query
    expresion, <number> is a positive integer, RESULT_KEYWORD can be
    STRUCTURE, ANY_PATH, BEGIN, or END, and QUERY_EXPRESSION is any
    legal query expression.

    For a full description of the CALLING relationship, see the
    on-line help file SCACOMMANDS.