Library /sys$common/syshlp/dbg$help.hlb DEBUG, SET, SCOPE, Description  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    By default, the debugger looks up a symbol specified without a
    path-name prefix according to the scope search list 0,1,2, . . .
    ,n, where n is the number of calls in the call stack. This
    scope search list is based on the current PC value and changes
    dynamically as the program executes. The default scope search
    list specifies that a symbol lookup such as EXAMINE X first looks
    for X in the routine that is currently executing (scope 0, also
    known as the PC scope); if no X is visible there, the debugger
    looks in the caller of that routine (scope 1), and so on down the
    call stack; if X is not found in scope n, the debugger searches
    the rest of the run-time symbol table (RST)-that is, all set
    modules and the global symbol table (GST), if necessary.

    In most cases, this default scope search list enables you
    to resolve ambiguities in a predictable, natural way that is
    consistent with language rules. But if you cannot access a symbol
    that is defined multiple times, use either of the following
    techniques:

    o  Specify the symbol with a path-name prefix. The path-name
       prefix consists of any nesting program units (for example,
       module\routine\block) that are necessary to specify the symbol
       uniquely. For example:

       DBG> EXAMINE MOD4\ROUT3\X
       DBG> TYPE MOD4\27

    o  Establish a new default scope (or a scope search list) for
       symbol lookup by using the SET SCOPE command. You can then
       specify the symbol without using a path-name prefix. For
       example:

       DBG> SET SCOPE MOD4\ROUT3
       DBG> EXAMINE X
       DBG> TYPE 27