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--- a/lib/kernel/doc/src/rpc.xml
+++ b/lib/kernel/doc/src/rpc.xml
@@ -25,328 +25,407 @@
<title>rpc</title>
<prepared>Claes Wikstrom</prepared>
<docno>1</docno>
- <date>96-09-10</date>
+ <date>1996-09-10</date>
<rev>A</rev>
</header>
<module>rpc</module>
- <modulesummary>Remote Procedure Call Services</modulesummary>
+ <modulesummary>Remote Procedure Call services.</modulesummary>
<description>
- <p>This module contains services which are similar to remote
- procedure calls. It also contains broadcast facilities and
+ <p>This module contains services similar to Remote
+ Procedure Calls. It also contains broadcast facilities and
parallel evaluators. A remote procedure call is a method to call
a function on a remote node and collect the answer. It is used
for collecting information on a remote node, or for running a
function with some specific side effects on the remote node.</p>
</description>
+
<datatypes>
<datatype>
<name name="key"/>
<desc>
- <p>As returned by <seealso marker="#async_call/4">
- <c>async_call/4</c>.</seealso></p>
+ <p>As returned by
+ <seealso marker="#async_call/4"><c>async_call/4</c></seealso>.</p>
</desc>
</datatype>
</datatypes>
+
<funcs>
<func>
- <name name="call" arity="4"/>
- <fsummary>Evaluate a function call on a node</fsummary>
+ <name name="abcast" arity="2"/>
+ <fsummary>Broadcast a message asynchronously to a registered process on
+ all nodes.</fsummary>
<desc>
- <p>Evaluates <c>apply(<anno>Module</anno>, <anno>Function</anno>, <anno>Args</anno>)</c> on the node
- <c><anno>Node</anno></c> and returns the corresponding value <c><anno>Res</anno></c>, or
- <c>{badrpc, <anno>Reason</anno>}</c> if the call fails.</p>
+ <p>Equivalent to <c>abcast([node()|nodes()], <anno>Name</anno>,
+ <anno>Msg</anno>)</c>.</p>
</desc>
</func>
+
<func>
- <name name="call" arity="5"/>
- <fsummary>Evaluate a function call on a node</fsummary>
+ <name name="abcast" arity="3"/>
+ <fsummary>Broadcast a message asynchronously to a registered process on
+ specific nodes.</fsummary>
<desc>
- <p>Evaluates <c>apply(<anno>Module</anno>, <anno>Function</anno>, <anno>Args</anno>)</c> on the node
- <c><anno>Node</anno></c> and returns the corresponding value <c><anno>Res</anno></c>, or
- <c>{badrpc, <anno>Reason</anno>}</c> if the call fails. <c><anno>Timeout</anno></c> is
- a timeout value in milliseconds. If the call times out,
- <c><anno>Reason</anno></c> is <c>timeout</c>.</p>
- <p>If the reply arrives after the call times out, no message
- will contaminate the caller's message queue, since this
- function spawns off a middleman process to act as (a void)
- destination for such an orphan reply. This feature also makes
- this function more expensive than <c>call/4</c> at
- the caller's end.</p>
+ <p>Broadcasts the message <c><anno>Msg</anno></c> asynchronously to
+ the registered process <c><anno>Name</anno></c> on the specified
+ nodes.</p>
</desc>
</func>
+
+ <func>
+ <name name="async_call" arity="4"/>
+ <fsummary>Evaluate a function call on a node, asynchronous
+ version.</fsummary>
+ <desc>
+ <p>Implements <em>call streams with promises</em>, a type of
+ RPC that does not suspend the caller until the result is
+ finished. Instead, a key is returned, which can be used
+ later to collect the value. The key can be viewed as a
+ promise to deliver the answer.</p>
+ <p>In this case, the key <c><anno>Key</anno></c> is returned, which
+ can be used in a subsequent call to
+ <seealso marker="#yield/1"><c>yield/1</c></seealso> or
+ <seealso marker="#nb_yield/1"><c>nb_yield/1,2</c></seealso>
+ to retrieve the value of evaluating <c>apply(<anno>Module</anno>,
+ <anno>Function</anno>, <anno>Args</anno>)</c> on node
+ <c><anno>Node</anno></c>.</p>
+ </desc>
+ </func>
+
<func>
<name name="block_call" arity="4"/>
- <fsummary>Evaluate a function call on a node in the RPC server's context</fsummary>
+ <fsummary>Evaluate a function call on a node in the RPC server's
+ context.</fsummary>
<desc>
- <p>Like <c>call/4</c>, but the RPC server at <c><anno>Node</anno></c> does
+ <p>Same as <seealso marker="#call/4"><c>call/4</c></seealso>,
+ but the RPC server at <c><anno>Node</anno></c> does
not create a separate process to handle the call. Thus,
this function can be used if the intention of the call is to
block the RPC server from any other incoming requests until
- the request has been handled. The function can also be used
+ the request has been handled. The function can also be used
for efficiency reasons when very small fast functions are
- evaluated, for example BIFs that are guaranteed not to
+ evaluated, for example, BIFs that are guaranteed not to
suspend.</p>
</desc>
</func>
+
<func>
<name name="block_call" arity="5"/>
- <fsummary>Evaluate a function call on a node in the RPC server's context</fsummary>
+ <fsummary>Evaluate a function call on a node in the RPC server's
+ context.</fsummary>
<desc>
- <p>Like <c>block_call/4</c>, but with a timeout value in
- the same manner as <c>call/5</c>.</p>
+ <p>Same as
+ <seealso marker="#block_call/4"><c>block_call/4</c></seealso>,
+ but with a time-out value in the same manner as
+ <seealso marker="#call/5"><c>call/5</c></seealso>.</p>
</desc>
</func>
+
<func>
- <name name="async_call" arity="4"/>
- <fsummary>Evaluate a function call on a node, asynchronous version</fsummary>
+ <name name="call" arity="4"/>
+ <fsummary>Evaluate a function call on a node.</fsummary>
<desc>
- <p>Implements <em>call streams with promises</em>, a type of
- RPC which does not suspend the caller until the result is
- finished. Instead, a key is returned which can be used at a
- later stage to collect the value. The key can be viewed as a
- promise to deliver the answer.</p>
- <p>In this case, the key <c><anno>Key</anno></c> is returned, which can be
- used in a subsequent call to <c>yield/1</c> or
- <c>nb_yield/1,2</c> to retrieve the value of evaluating
- <c>apply(<anno>Module</anno>, <anno>Function</anno>, <anno>Args</anno>)</c> on the node <c><anno>Node</anno></c>.</p>
+ <p>Evaluates <c>apply(<anno>Module</anno>, <anno>Function</anno>,
+ <anno>Args</anno>)</c> on node <c><anno>Node</anno></c> and returns
+ the corresponding value <c><anno>Res</anno></c>, or
+ <c>{badrpc, <anno>Reason</anno>}</c> if the call fails.</p>
</desc>
</func>
+
<func>
- <name name="yield" arity="1"/>
- <fsummary>Deliver the result of evaluating a function call on a node (blocking)</fsummary>
+ <name name="call" arity="5"/>
+ <fsummary>Evaluate a function call on a node.</fsummary>
<desc>
- <p>Returns the promised answer from a previous
- <c>async_call/4</c>. If the answer is available, it is
- returned immediately. Otherwise, the calling process is
- suspended until the answer arrives from <c>Node</c>.</p>
+ <p>Evaluates <c>apply(<anno>Module</anno>, <anno>Function</anno>,
+ <anno>Args</anno>)</c> on node <c><anno>Node</anno></c> and returns
+ the corresponding value <c><anno>Res</anno></c>, or
+ <c>{badrpc, <anno>Reason</anno>}</c> if the call fails.
+ <c><anno>Timeout</anno></c> is
+ a time-out value in milliseconds. If the call times out,
+ <c><anno>Reason</anno></c> is <c>timeout</c>.</p>
+ <p>If the reply arrives after the call times out, no message
+ contaminates the caller's message queue, as this
+ function spawns off a middleman process to act as (a void)
+ destination for such an orphan reply. This feature also makes
+ this function more expensive than <c>call/4</c> at
+ the caller's end.</p>
</desc>
</func>
+
<func>
- <name name="nb_yield" arity="1"/>
- <fsummary>Deliver the result of evaluating a function call on a node (non-blocking)</fsummary>
+ <name name="cast" arity="4"/>
+ <fsummary>Run a function on a node ignoring the result.</fsummary>
<desc>
- <p>Equivalent to <c>nb_yield(<anno>Key</anno>, 0)</c>.</p>
+ <p>Evaluates <c>apply(<anno>Module</anno>, <anno>Function</anno>,
+ <anno>Args</anno>)</c> on node
+ <c><anno>Node</anno></c>. No response is delivered and the calling
+ process is not suspended until the evaluation is complete, as
+ is the case with
+ <seealso marker="#call/4"><c>call/4,5</c></seealso>.</p>
</desc>
</func>
+
<func>
- <name name="nb_yield" arity="2"/>
- <fsummary>Deliver the result of evaluating a function call on a node (non-blocking)</fsummary>
+ <name name="eval_everywhere" arity="3"/>
+ <fsummary>Run a function on all nodes, ignoring the result.</fsummary>
+ <desc>
+ <p>Equivalent to <c>eval_everywhere([node()|nodes()],
+ <anno>Module</anno>, <anno>Function</anno>,
+ <anno>Args</anno>)</c>.</p>
+ </desc>
+ </func>
+
+ <func>
+ <name name="eval_everywhere" arity="4"/>
+ <fsummary>Run a function on specific nodes, ignoring the
+ result.</fsummary>
+ <desc>
+ <p>Evaluates <c>apply(<anno>Module</anno>, <anno>Function</anno>,
+ <anno>Args</anno>)</c> on
+ the specified nodes. No answers are collected.</p>
+ </desc>
+ </func>
+
+ <func>
+ <name name="multi_server_call" arity="2"/>
+ <fsummary>Interact with the servers on a number of nodes.</fsummary>
+ <desc>
+ <p>Equivalent to <c>multi_server_call([node()|nodes()],
+ <anno>Name</anno>, <anno>Msg</anno>)</c>.</p>
+ </desc>
+ </func>
+
+ <func>
+ <name name="multi_server_call" arity="3"/>
+ <fsummary>Interact with the servers on a number of nodes.</fsummary>
<desc>
- <p>This is a non-blocking version of <c>yield/1</c>. It returns
- the tuple <c>{value, <anno>Val</anno>}</c> when the computation has
- finished, or <c>timeout</c> when <c><anno>Timeout</anno></c> milliseconds
- has elapsed.</p>
+ <p>Can be used when interacting with servers called
+ <c><anno>Name</anno></c> on the specified nodes. It is assumed that
+ the servers receive messages in the format
+ <c>{From, <anno>Msg</anno>}</c> and reply using
+ <c>From ! {<anno>Name</anno>, Node, <anno>Reply</anno>}</c>, where
+ <c>Node</c> is the name of the node where the server is located.
+ The function returns <c>{<anno>Replies</anno>,
+ <anno>BadNodes</anno>}</c>, where <c><anno>Replies</anno></c> is a
+ list of all <c><anno>Reply</anno></c> values, and
+ <c><anno>BadNodes</anno></c> is one of the following:</p>
+ <list type="bulleted">
+ <item>A list of the nodes that do not exist</item>
+ <item>A list of the nodes where the server does not exist</item>
+ <item>A list of the nodes where the server terminatd before sending
+ any reply.</item>
+ </list>
</desc>
</func>
+
<func>
<name name="multicall" arity="3"/>
- <fsummary>Evaluate a function call on a number of nodes</fsummary>
+ <fsummary>Evaluate a function call on a number of nodes.</fsummary>
<desc>
- <p>Equivalent to <c>multicall([node()|nodes()], <anno>Module</anno>, <anno>Function</anno>, <anno>Args</anno>, infinity)</c>.</p>
+ <p>Equivalent to <c>multicall([node()|nodes()], <anno>Module</anno>,
+ <anno>Function</anno>, <anno>Args</anno>, infinity)</c>.</p>
</desc>
</func>
+
<func>
<name name="multicall" arity="4" clause_i="1"/>
- <fsummary>Evaluate a function call on a number of nodes</fsummary>
+ <fsummary>Evaluate a function call on a number of nodes.</fsummary>
<desc>
- <p>Equivalent to <c>multicall(<anno>Nodes</anno>, <anno>Module</anno>, <anno>Function</anno>, <anno>Args</anno>, infinity)</c>.</p>
+ <p>Equivalent to <c>multicall(<anno>Nodes</anno>, <anno>Module</anno>,
+ <anno>Function</anno>, <anno>Args</anno>, infinity)</c>.</p>
</desc>
</func>
+
<func>
<name name="multicall" arity="4" clause_i="2"/>
- <fsummary>Evaluate a function call on a number of nodes</fsummary>
+ <fsummary>Evaluate a function call on a number of nodes.</fsummary>
<desc>
- <p>Equivalent to <c>multicall([node()|nodes()], <anno>Module</anno>, <anno>Function</anno>, <anno>Args</anno>, <anno>Timeout</anno>)</c>.</p>
+ <p>Equivalent to <c>multicall([node()|nodes()], <anno>Module</anno>,
+ <anno>Function</anno>, <anno>Args</anno>,
+ <anno>Timeout</anno>)</c>.</p>
</desc>
</func>
+
<func>
<name name="multicall" arity="5"/>
- <fsummary>Evaluate a function call on a number of nodes</fsummary>
+ <fsummary>Evaluate a function call on a number of nodes.</fsummary>
<desc>
- <p>In contrast to an RPC, a multicall is an RPC which is sent
+ <p>In contrast to an RPC, a multicall is an RPC that is sent
concurrently from one client to multiple servers. This is
- useful for collecting some information from a set of nodes,
+ useful for collecting information from a set of nodes,
or for calling a function on a set of nodes to achieve some
side effects. It is semantically the same as iteratively
making a series of RPCs on all the nodes, but the multicall
- is faster as all the requests are sent at the same time
+ is faster, as all the requests are sent at the same time
and are collected one by one as they come back.</p>
- <p>The function evaluates <c>apply(<anno>Module</anno>, <anno>Function</anno>, <anno>Args</anno>)</c>
- on the specified nodes and collects the answers. It returns
- <c>{<anno>ResL</anno>, <anno>BadNodes</anno>}</c>, where <c><anno>BadNodes</anno></c> is a list
+ <p>The function evaluates <c>apply(<anno>Module</anno>,
+ <anno>Function</anno>, <anno>Args</anno>)</c>
+ on the specified nodes and collects the answers. It returns
+ <c>{<anno>ResL</anno>, <anno>BadNodes</anno>}</c>, where
+ <c><anno>BadNodes</anno></c> is a list
of the nodes that terminated or timed out during computation,
and <c><anno>ResL</anno></c> is a list of the return values.
<c><anno>Timeout</anno></c> is a time (integer) in milliseconds, or
<c>infinity</c>.</p>
<p>The following example is useful when new object code is to
- be loaded on all nodes in the network, and also indicates
- some side effects RPCs may produce:</p>
+ be loaded on all nodes in the network, and indicates
+ some side effects that RPCs can produce:</p>
<code type="none">
-%% Find object code for module Mod
-{Mod, Bin, File} = code:get_object_code(Mod),
+%% Find object code for module Mod
+{Mod, Bin, File} = code:get_object_code(Mod),
-%% and load it on all nodes including this one
+%% and load it on all nodes including this one
{ResL, _} = rpc:multicall(code, load_binary, [Mod, File, Bin]),
%% and then maybe check the ResL list.</code>
</desc>
</func>
+
<func>
- <name name="cast" arity="4"/>
- <fsummary>Run a function on a node ignoring the result</fsummary>
- <desc>
- <p>Evaluates <c>apply(<anno>Module</anno>, <anno>Function</anno>, <anno>Args</anno>)</c> on the node
- <c><anno>Node</anno></c>. No response is delivered and the calling
- process is not suspended until the evaluation is complete, as
- is the case with <c>call/4,5</c>.</p>
- </desc>
- </func>
- <func>
- <name name="eval_everywhere" arity="3"/>
- <fsummary>Run a function on all nodes, ignoring the result</fsummary>
- <desc>
- <p>Equivalent to <c>eval_everywhere([node()|nodes()], <anno>Module</anno>, <anno>Function</anno>, <anno>Args</anno>)</c>.</p>
- </desc>
- </func>
- <func>
- <name name="eval_everywhere" arity="4"/>
- <fsummary>Run a function on specific nodes, ignoring the result</fsummary>
- <desc>
- <p>Evaluates <c>apply(<anno>Module</anno>, <anno>Function</anno>, <anno>Args</anno>)</c> on
- the specified nodes. No answers are collected.</p>
- </desc>
- </func>
- <func>
- <name name="abcast" arity="2"/>
- <fsummary>Broadcast a message asynchronously to a registered process on all nodes</fsummary>
- <desc>
- <p>Equivalent to <c>abcast([node()|nodes()], <anno>Name</anno>, <anno>Msg</anno>)</c>.</p>
- </desc>
- </func>
- <func>
- <name name="abcast" arity="3"/>
- <fsummary>Broadcast a message asynchronously to a registered process on specific nodes</fsummary>
+ <name name="nb_yield" arity="1"/>
+ <fsummary>Deliver the result of evaluating a function call on a node
+ (non-blocking).</fsummary>
<desc>
- <p>Broadcasts the message <c><anno>Msg</anno></c> asynchronously to
- the registered process <c><anno>Name</anno></c> on the specified nodes.</p>
+ <p>Equivalent to <c>nb_yield(<anno>Key</anno>, 0)</c>.</p>
</desc>
</func>
+
<func>
- <name name="sbcast" arity="2"/>
- <fsummary>Broadcast a message synchronously to a registered process on all nodes</fsummary>
+ <name name="nb_yield" arity="2"/>
+ <fsummary>Deliver the result of evaluating a function call on a node
+ (non-blocking).</fsummary>
<desc>
- <p>Equivalent to <c>sbcast([node()|nodes()], <anno>Name</anno>, <anno>Msg</anno>)</c>.</p>
+ <p>Non-blocking version of
+ <seealso marker="#yield/1"><c>yield/1</c></seealso>. It returns
+ the tuple <c>{value, <anno>Val</anno>}</c> when the computation is
+ finished, or <c>timeout</c> when <c><anno>Timeout</anno></c>
+ milliseconds has elapsed.</p>
</desc>
</func>
+
<func>
- <name name="sbcast" arity="3"/>
- <fsummary>Broadcast a message synchronously to a registered process on specific nodes</fsummary>
+ <name name="parallel_eval" arity="1"/>
+ <fsummary>Evaluate many function calls on all nodes in
+ parallel.</fsummary>
<desc>
- <p>Broadcasts the message <c><anno>Msg</anno></c> synchronously to
- the registered process <c><anno>Name</anno></c> on the specified nodes.</p>
- <p>Returns <c>{<anno>GoodNodes</anno>, <anno>BadNodes</anno>}</c>, where <c><anno>GoodNodes</anno></c>
- is the list of nodes which have <c><anno>Name</anno></c> as a registered
- process.</p>
- <p>The function is synchronous in the sense that it is known
- that all servers have received the message when the call
- returns. It is not possible to know that the servers have
- actually processed the message.</p>
- <p>Any further messages sent to the servers, after this
- function has returned, will be received by all servers after
- this message.</p>
+ <p>Evaluates, for every tuple in <c><anno>FuncCalls</anno></c>,
+ <c>apply(<anno>Module</anno>, <anno>Function</anno>,
+ <anno>Args</anno>)</c> on some node in
+ the network. Returns the list of return values, in the same
+ order as in <c><anno>FuncCalls</anno></c>.</p>
</desc>
</func>
+
<func>
- <name name="server_call" arity="4"/>
- <fsummary>Interact with a server on a node</fsummary>
+ <name name="pinfo" arity="1"/>
+ <fsummary>Information about a process.</fsummary>
<desc>
- <p>This function can be used when interacting with a server
- called <c><anno>Name</anno></c> at node <c><anno>Node</anno></c>. It is assumed that
- the server receives messages in the format
- <c>{From, <anno>Msg</anno>}</c> and replies using <c>From ! {<anno>ReplyWrapper</anno>, <anno>Node</anno>, <anno>Reply</anno>}</c>. This function makes such
- a server call and ensures that the entire call is packed into
- an atomic transaction which either succeeds or fails. It
- never hangs, unless the server itself hangs.</p>
- <p>The function returns the answer <c><anno>Reply</anno></c> as produced by
- the server <c><anno>Name</anno></c>, or <c>{error, <anno>Reason</anno>}</c>.</p>
+ <p>Location transparent version of the BIF
+ <seealso marker="erts:erlang#process_info/1"><c>erlang:process_info/1</c></seealso> in <c>ERTS</c>.</p>
</desc>
</func>
+
<func>
- <name name="multi_server_call" arity="2"/>
- <fsummary>Interact with the servers on a number of nodes</fsummary>
+ <name name="pinfo" arity="2"/>
+ <fsummary>Information about a process.</fsummary>
<desc>
- <p>Equivalent to <c>multi_server_call([node()|nodes()], <anno>Name</anno>, <anno>Msg</anno>)</c>.</p>
+ <p>Location transparent version of the BIF
+ <seealso marker="erts:erlang#process_info/2"><c>erlang:process_info/2</c></seealso> in <c>ERTS</c>.</p>
</desc>
</func>
+
<func>
- <name name="multi_server_call" arity="3"/>
- <fsummary>Interact with the servers on a number of nodes</fsummary>
+ <name name="pmap" arity="3"/>
+ <fsummary>Parallell evaluation of mapping a function over a
+ list.</fsummary>
<desc>
- <p>This function can be used when interacting with servers
- called <c><anno>Name</anno></c> on the specified nodes. It is assumed that
- the servers receive messages in the format <c>{From, <anno>Msg</anno>}</c>
- and reply using <c>From ! {<anno>Name</anno>, Node, <anno>Reply</anno>}</c>, where
- <c>Node</c> is the name of the node where the server is
- located. The function returns <c>{<anno>Replies</anno>, <anno>BadNodes</anno>}</c>,
- where <c><anno>Replies</anno></c> is a list of all <c><anno>Reply</anno></c> values and
- <c><anno>BadNodes</anno></c> is a list of the nodes which did not exist, or
- where the server did not exist, or where the server terminated
- before sending any reply.</p>
+ <p>Evaluates <c>apply(<anno>Module</anno>, <anno>Function</anno>,
+ [<anno>Elem</anno>|<anno>ExtraArgs</anno>])</c> for every element
+ <c><anno>Elem</anno></c> in <c><anno>List1</anno></c>, in parallel.
+ Returns the list of return values, in the same order as in
+ <c><anno>List1</anno></c>.</p>
</desc>
</func>
+
<func>
<name name="safe_multi_server_call" arity="2"/>
<name name="safe_multi_server_call" arity="3"/>
- <fsummary>Interact with the servers on a number of nodes (deprecated)</fsummary>
+ <fsummary>Interact with the servers on a number of nodes
+ (deprecated).</fsummary>
<desc>
<warning>
- <p>This function is deprecated. Use
- <c>multi_server_call/2,3</c> instead.</p>
+ <p>Deprecated. Use
+ <seealso marker="#multi_server_call/2"><c>multi_server_call/2,3</c></seealso>
+ instead.</p>
</warning>
<p>In Erlang/OTP R6B and earlier releases,
<c>multi_server_call/2,3</c> could not handle the case
where the remote node exists, but there is no server called
- <c><anno>Name</anno></c>. Instead this function had to be used. In
+ <c><anno>Name</anno></c>. Instead, this function had to be used. In
Erlang/OTP R7B and later releases, however, the functions are
- equivalent, except for this function being slightly slower.</p>
+ equivalent, except that this function is slightly slower.</p>
</desc>
</func>
+
<func>
- <name name="parallel_eval" arity="1"/>
- <fsummary>Evaluate several function calls on all nodes in parallel</fsummary>
+ <name name="sbcast" arity="2"/>
+ <fsummary>Broadcast a message synchronously to a registered process on
+ all nodes.</fsummary>
<desc>
- <p>For every tuple in <c><anno>FuncCalls</anno></c>, evaluates
- <c>apply(<anno>Module</anno>, <anno>Function</anno>, <anno>Args</anno>)</c> on some node in
- the network. Returns the list of return values, in the same
- order as in <c><anno>FuncCalls</anno></c>.</p>
+ <p>Equivalent to <c>sbcast([node()|nodes()], <anno>Name</anno>,
+ <anno>Msg</anno>)</c>.</p>
</desc>
</func>
+
<func>
- <name name="pmap" arity="3"/>
- <fsummary>Parallell evaluation of mapping a function over a list </fsummary>
+ <name name="sbcast" arity="3"/>
+ <fsummary>Broadcast a message synchronously to a registered process on
+ specific nodes.</fsummary>
<desc>
- <p>Evaluates <c>apply(<anno>Module</anno>, <anno>Function</anno>, [<anno>Elem</anno>|<anno>ExtraArgs</anno>])</c>,
- for every element <c><anno>Elem</anno></c> in <c><anno>List1</anno></c>, in parallel.
- Returns the list of return values, in the same order as in
- <c><anno>List1</anno></c>.</p>
+ <p>Broadcasts the message <c><anno>Msg</anno></c> synchronously to
+ the registered process <c><anno>Name</anno></c> on the specified
+ nodes.</p>
+ <p>Returns <c>{<anno>GoodNodes</anno>, <anno>BadNodes</anno>}</c>,
+ where <c><anno>GoodNodes</anno></c> is the list of nodes that have
+ <c><anno>Name</anno></c> as a registered process.</p>
+ <p>The function is synchronous in the sense that it is known
+ that all servers have received the message when the call
+ returns. It is not possible to know that the servers have
+ processed the message.</p>
+ <p>Any further messages sent to the servers, after this
+ function has returned, are received by all servers after
+ this message.</p>
</desc>
</func>
+
<func>
- <name name="pinfo" arity="1"/>
- <fsummary>Information about a process</fsummary>
+ <name name="server_call" arity="4"/>
+ <fsummary>Interact with a server on a node.</fsummary>
<desc>
- <p>Location transparent version of the BIF
- <seealso marker="erts:erlang#process_info/1">
- <c>process_info/1</c></seealso>.</p>
+ <p>Can be used when interacting with a server called
+ <c><anno>Name</anno></c> on node <c><anno>Node</anno></c>. It is
+ assumed that the server receives messages in the format
+ <c>{From, <anno>Msg</anno>}</c> and replies using
+ <c>From ! {<anno>ReplyWrapper</anno>, <anno>Node</anno>,
+ <anno>Reply</anno>}</c>. This function makes such
+ a server call and ensures that the entire call is packed into
+ an atomic transaction, which either succeeds or fails. It
+ never hangs, unless the server itself hangs.</p>
+ <p>The function returns the answer <c><anno>Reply</anno></c> as
+ produced by the server <c><anno>Name</anno></c>, or
+ <c>{error, <anno>Reason</anno>}</c>.</p>
</desc>
</func>
+
<func>
- <name name="pinfo" arity="2"/>
- <fsummary>Information about a process</fsummary>
+ <name name="yield" arity="1"/>
+ <fsummary>Deliver the result of evaluating a function call on a node
+ (blocking).</fsummary>
<desc>
- <p>Location transparent version of the BIF
- <seealso marker="erts:erlang#process_info/2">
- <c>process_info/2</c></seealso>.</p>
+ <p>Returns the promised answer from a previous
+ <seealso marker="#async_call/4"><c>async_call/4</c></seealso>.
+ If the answer is available, it is
+ returned immediately. Otherwise, the calling process is
+ suspended until the answer arrives from <c>Node</c>.</p>
</desc>
</func>
</funcs>