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[;1m nodes()[0m
Returns a list of all nodes connected to this node through normal
connections (that is, hidden nodes are not listed). Same as
nodes(visible).
[;1m nodes(Arg)[0m
Returns a list of nodes according to the argument specified. The
returned result, when the argument is a list, is the list of nodes
satisfying the disjunction(s) of the list elements.
[;;4mNodeType[0ms:
• [;;4mvisible[0m - Nodes connected to this node through normal
connections.
• [;;4mhidden[0m - Nodes connected to this node through hidden
connections.
• [;;4mconnected[0m - All nodes connected to this node.
• [;;4mthis[0m - This node.
• [;;4mknown[0m - Nodes that are known to this node. That is,
connected nodes and nodes referred to by process
identifiers, port identifiers, and references located on
this node. The set of known nodes is garbage collected.
Notice that this garbage collection can be delayed. For more
information, see [;;4merlang:system_info(delayed_node_table_gc)[0m.
Some equalities: [;;4m[node()] = nodes(this)[0m, [;;4mnodes(connected) =[0m
[;;4mnodes([visible, hidden])[0m, and [;;4mnodes() = nodes(visible)[0m.
[;1m nodes(Arg, InfoOpts)[0m
[;;4mSince[0m:
OTP 25.1
Returns a list of [;;4mNodeInfo[0m tuples.
The first element is the node name. Nodes to be included in the
list are determined by the first argument [;;4mArg[0m in the same way as
for [;;4mnodes(Arg)[0m. The second element of [;;4mNodeInfo[0m tuples is a map
containing further information about the node identified by the
first element. The information present in this map is determined
by the [;;4mInfoOpts[0m map passed as the second argument. Currently the
following associations are allowed in the [;;4mInfoOpts[0m map:
• [;;4mconnection_id => boolean()[0m - If the value of the
association equals [;;4mtrue[0m, the [;;4mInfo[0m map in the returned
result will contain the key [;;4mconnection_id[0m associated with
the value [;;4mConnectionId[0m. If [;;4mConnectionId[0m equals [;;4m[0m
[;;4mundefined[0m, the node is not connected to the node which the
caller is executing on, or is the node which the caller is
executing on. If [;;4mConnectionId[0m is an integer, the node is
currently connected to the node which the caller is
executing on.
The integer connection identifier value together with a node
name identifies a specific connection instance to the node
with that node name. The connection identifier value is node
local. That is, on the other node the connection identifier
will not be the same value. If a connection is taken down
and then taken up again, the connection identifier value
will change for the connection to that node. The amount of
values for connection identifiers are limited, so it is
possible to see the same value for different instances, but
quite unlikely. It is undefined how the value change between
two consecutive connection instances.
• [;;4mnode_type => boolean()[0m - If the value of the association
equals [;;4mtrue[0m, the [;;4mInfo[0m map in the returned result will
contain the key [;;4mnode_type[0m associated with the value [;;4m[0m
[;;4mNodeTypeInfo[0m. Currently the following node types exist:
￮ [;;4mvisible[0m - The node is connected to the node of the
calling process through an ordinary visible
connection. That is, the node name would appear in the
result returned by [;;4mnodes/0[0m.
￮ [;;4mhidden[0m - The node is connected to the node of the
calling process through a hidden connection. That is,
the node name would not appear in the result
returned by [;;4mnodes/0[0m.
￮ [;;4mthis[0m - This is the node of the calling process.
￮ [;;4mknown[0m - The node is not connected but known to the
node of the calling process.
Example:
(a@localhost)1> nodes([this, connected], #{connection_id=>true, node_type=>true}).
[{c@localhost,#{connection_id => 13892108,node_type => hidden}},
{b@localhost,#{connection_id => 3067553,node_type => visible}},
{a@localhost,#{connection_id => undefined,node_type => this}}]
(a@localhost)2>
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