The possible flags, their values and their meanings are:
    Flags              Values           Description
   ----------------------------------------------------------------------
    auxiliary          on,off           predicate is a compiler auxiliary
    break_lines        list of          list of predicate source File:Line
                       atom:integer     that currently have breakpoints set
    call_type          prolog,          predicate calling external convention
    code_size          an integer       size of abstract machine
                                        code in words (32/64 bits)
    debugged           on, off          compiled in debugging mode
    declared           on, off          predicate was declared
    defined            on, off          predicate code exists
    definition_module  an atom          where the procedure is defined
    demon              on, off          predicate is a demon
    deprecated         on, off          predicate is deprecated,
                                        warning on use
    leash              stop,print,      see below
                       notrace
    mode               pred(Mode1,...)  the mode of the predicate
    parallel           on, off          clauses may be executed in parallel
    port_calls         list of          list of DefModule:Name/Arity for
                       atom:atom/int    the predicate's body goals where 
                                        breakpoints can be added. The 
                                        port_lines option returns the source
                                        information for these ports, in the 
                                        same order
    port_lines         list of          list of predicate source File:Line
                       atom:integer     where breakpoints can be added. The
                                        port_calls option returns the goal
                                        information for these ports, in the 
                                        same order 
    priority           1..12            waking priority
    skip               on, off          procedure will be traced,
                                        but its children will not
    spy                on, off          procedure has a spypoint
    stability          static,dynamic   is the procedure dynamic?
    tool               on, off          tool property
    type               built-in,user    type of predicate
    visibility         local,exported   module scope
                       reexported,
                       imported
    source_file        an atom          the file where defined
    source_line        an integer       starting line number in the file
    source_offset      an integer       byte offset at which the procedure
                                        definition starts in its source file
   The possible values of leash and their meanings are:
----------------------------------------------------- | Values Description | |-------------------------------------------------- | | stop procedure ports are printed and the | | debugger stops on them | | print procedure ports are printed and the | | debugger does not stop on them | | notrace procedure ports will not be shown, but | | its childrens's ports will | -----------------------------------------------------|
Success:
    [eclipse]: get_flag(member/2, F, V),
            printf("%-20s%w\n", [F, V]), fail.
    mode                member(?, ?)
    call_type           prolog
    debugged            off
    declared            on
    autoload            off
    auxiliary           off
    defined             on
    leash               stop
    skip                off
    spy                 off
    start_tracing       off
    stability           static
    tool                off
    type                built_in
    visibility          imported
    priority            2
    demon               off
    parallel            off
    definition_module   sepia_kernel
Fail:
    get_flag(true/0, defined, off).
    get_flag(undef/0, F, V).
Error:
    get_flag(X, spy, on).           (Error 4).
    get_flag("a", spy, on).         (Error 5).