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@bnoordhuis bnoordhuis/dgram.markdown.patch Secret
Created Aug 22, 2011

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diff --git a/doc/api/dgram.markdown b/doc/api/dgram.markdown
index cc2aea2..2d41594 100644
--- a/doc/api/dgram.markdown
+++ b/doc/api/dgram.markdown
@@ -31,6 +31,11 @@ Creates a datagram socket of the specified types. Valid types are:
Takes an optional callback which is added as a listener for `message` events.
+Call `socket.bind` if you want to receive datagrams. `socket.bind()` will bind
+to the "all interfaces" address on a random port (it does the right thing for
+both `udp4` and `udp6` sockets). You can then retrieve the address and port
+with `socket.address().address` and `socket.address().port`.
+
### dgram.send(buf, offset, length, path, [callback])
For Unix domain datagram sockets, the destination address is a pathname in the filesystem.
@@ -61,6 +66,10 @@ re-used. Note that DNS lookups will delay the time that a send takes place, at
least until the next tick. The only way to know for sure that a send has taken place
is to use the callback.
+If the socket has not been previously bound with a call to `bind`, it's
+assigned a random port number and bound to the "all interfaces" address
+(0.0.0.0 for IPv4-only systems, ::0 for IPv6 and dual stack systems).
+
Example of sending a UDP packet to a random port on `localhost`;
var dgram = require('dgram');
@@ -142,8 +151,7 @@ Example of a UDP server listening on port 41234:
### dgram.close()
-Close the underlying socket and stop listening for data on it. UDP sockets
-automatically listen for messages, even if they did not call `bind()`.
+Close the underlying socket and stop listening for data on it.
### dgram.address()
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