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[;1m-spec alias(Opts) -> Alias[0m
[;1m when[0m
[;1m Alias :: reference(),[0m
[;1m Opts :: [explicit_unalias | reply].[0m
[;;4mSince[0m:
OTP 24.0
Create an alias which can be used when sending messages to the
process that created the alias. When the alias has been
deactivated, messages sent using the alias will be dropped. An
alias can be deactivated using [;;4munalias/1[0m. Currently available
options for [;;4malias/1[0m:
[;;4m[;;4mexplicit_unalias[0m[0m:
The alias can only be deactivated via a call to [;;4munalias/1[0m.
This is also the default behaviour if no options are passed or
if [;;4malias/0[0m is called.
[;;4m[;;4mreply[0m[0m:
The alias will be automatically deactivated when a reply
message sent via the alias is received. The alias can also
still be deactivated via a call to [;;4munalias/1[0m.
Example:
server() ->
receive
{request, AliasReqId, Request} ->
Result = perform_request(Request),
AliasReqId ! {reply, AliasReqId, Result}
end,
server().
client(ServerPid, Request) ->
AliasReqId = alias([reply]),
ServerPid ! {request, AliasReqId, Request},
%% Alias will be automatically deactivated if we receive a reply
%% since we used the 'reply' option...
receive
{reply, AliasReqId, Result} -> Result
after 5000 ->
unalias(AliasReqId),
%% Flush message queue in case the reply arrived
%% just before the alias was deactivated...
receive {reply, AliasReqId, Result} -> Result
after 0 -> exit(timeout)
end
end.
Note that both the server and the client in this example must be
executing on at least OTP 24 systems in order for this to work.
For more information on process aliases see the Process Aliases
section of the Erlang Reference Manual.
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