NAME
        CxMsgID -- obtain the ID of a commodity message. (V36)

   SYNOPSIS
        id = CxMsgID(cxm);
        D0           A0

        long cxmsgid(struct cxmsg *);

   FUNCTION
        This function returns the value associated with the cause or source
        of the commodity message 'cxm'. Values are provided by the application
        when a sender or custom object is created.

   INPUTS
        cxm - the commodity message to inquire about (must NOT be NULL)

   RESULTS
        id - if not specified by the application, the ID value of a
             commodity message will be 0. It is suggested that using
             non-zero values in your program as a rule may identify some
             possible errors.

   SEE ALSO
        cx_lib/cxsender(), cx_lib/cxcustom()