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  • Committer: Bazaar Package Importer
  • Author(s): Erlang Packagers, Sergei Golovan
  • Date: 2006-12-03 17:07:44 UTC
  • mfrom: (2.1.11 feisty)
  • Revision ID: james.westby@ubuntu.com-20061203170744-rghjwupacqlzs6kv
Tags: 1:11.b.2-4
[ Sergei Golovan ]
Fixed erlang-base and erlang-base-hipe prerm scripts.

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erts/example/next_perm.erl
 
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-module(next_perm).
 
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-export([next_perm/1, prev_perm/1, load/0, all_perm/1]).
 
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load() ->
 
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    case whereis(next_perm) of
 
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        undefined ->
 
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            case erl_ddll:load_driver(".", "next_perm") of
 
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                ok -> ok;
 
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                {error, already_loaded} -> ok;
 
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                E -> exit(E)
 
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            end,
 
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            Port = open_port({spawn, "next_perm"}, []),
 
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            register(next_perm, Port);
 
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        _ ->
 
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            ok
 
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    end.
 
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list_to_integer_binaries(L) ->
 
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    [<<I:32/integer-native>> || I <- L].
 
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next_perm(L) ->
 
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    next_perm(L, 1).
 
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prev_perm(L) ->
 
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    next_perm(L, 2).
 
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next_perm(L, Nxt) ->
 
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    load(),
 
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    B = list_to_integer_binaries(L),
 
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    Port = whereis(next_perm),
 
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    port_command(Port, [Nxt, B]),
 
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    receive
 
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        [Port | Result] ->
 
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            Result
 
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    end.
 
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all_perm(L) ->
 
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    New = prev_perm(L),
 
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    all_perm(New, L, [New]).
 
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all_perm(L, L, Acc) ->
 
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    Acc;
 
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all_perm(L, Orig, Acc) ->
 
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    New = prev_perm(L),
 
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    all_perm(New, Orig, [New | Acc]).
 
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