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-rw-r--r--lib/kernel/doc/src/gen_sctp.xml31
-rw-r--r--lib/kernel/doc/src/gen_tcp.xml6
-rw-r--r--lib/kernel/doc/src/gen_udp.xml17
-rw-r--r--lib/kernel/doc/src/inet.xml104
-rw-r--r--lib/kernel/doc/src/notes.xml60
5 files changed, 192 insertions, 26 deletions
diff --git a/lib/kernel/doc/src/gen_sctp.xml b/lib/kernel/doc/src/gen_sctp.xml
index dacea7a239..986260638d 100644
--- a/lib/kernel/doc/src/gen_sctp.xml
+++ b/lib/kernel/doc/src/gen_sctp.xml
@@ -496,9 +496,11 @@
orthogonal to the sets of TCP, UDP and generic INET options:
only those options which are explicitly listed below are allowed
for SCTP sockets. Options can be set on the socket using
- <c>gen_sctp:open/1,2</c> or <c>inet:setopts/2</c>,
- retrieved using <c>inet:getopts/2</c>, and when calling
- <c>gen_sctp:connect/4,5</c> options can be changed.</p>
+ <seealso marker="#open/1"><c>gen_sctp:open/1,2</c></seealso>
+ or <seealso marker="inet#setopts/2"><c>inet:setopts/2</c></seealso>,
+ retrieved using <seealso marker="inet#getopts/2"><c>inet:getopts/2</c></seealso>,
+ and when calling <seealso marker="#connect/4"><c>gen_sctp:connect/4,5</c></seealso>
+ options can be changed.</p>
<marker id="option-binary"></marker>
<marker id="option-list"></marker>
<taglist>
@@ -507,7 +509,7 @@
<p>Determines the type of data returned from <c>gen_sctp:recv/1,2</c>.</p>
<marker id="option-active"></marker>
</item>
- <tag><c>{active, true|false|once}</c></tag>
+ <tag><c>{active, true|false|once|N}</c></tag>
<item>
<list type="bulleted">
<item>
@@ -524,11 +526,28 @@
</item>
<item>
<p>If <c>once</c>, only one message is automatically placed
- in the message queue, after that the mode is automatically
- re-set to passive. This provides flow control as well as
+ in the message queue, and after that the mode is automatically
+ reset to passive. This provides flow control as well as
the possibility for the receiver to listen for its incoming
SCTP data interleaved with other inter-process messages.</p>
</item>
+ <item>
+ <p>If <c>active</c> is specified as an integer <c>N</c> in the
+ range -32768 to 32767 (inclusive), then that number is added to
+ the socket's count of the number of data messages to be
+ delivered to the controlling process. If the result of the
+ addition would be negative, the count is set to 0. Once the
+ count reaches 0, either through the delivery of messages or by
+ being explicitly set with <seealso
+ marker="inet#setopts/2">inet:setopts/2</seealso>, the socket's
+ mode is automatically reset to passive (<c>{active,
+ false}</c>) mode. When a socket in this active mode transitions to
+ passive mode, the message <c>{sctp_passive, Socket}</c> is sent
+ to the controlling process to notify it that if it wants to
+ receive more data messages from the socket, it must call
+ <seealso marker="inet#setopts/2">inet:setopts/2</seealso> to set
+ the socket back into an active mode.</p>
+ </item>
</list>
</item>
<tag><c>{tos, integer()}</c></tag>
diff --git a/lib/kernel/doc/src/gen_tcp.xml b/lib/kernel/doc/src/gen_tcp.xml
index 7afd73f4bf..dbd0d3c815 100644
--- a/lib/kernel/doc/src/gen_tcp.xml
+++ b/lib/kernel/doc/src/gen_tcp.xml
@@ -148,6 +148,12 @@ do_recv(Sock, Bs) ->
as messages:</p>
<code type="none">
{tcp, Socket, Data}</code>
+ <p>If the socket is in <c>{active, N}</c> mode (see <seealso marker="inet#setopts/2">
+ inet:setopts/2</seealso> for details) and its message counter
+ drops to 0, the following message is delivered to indicate that the
+ socket has transitioned to passive (<c>{active, false}</c>) mode:</p>
+ <code type="none">
+{tcp_passive, Socket}</code>
<p>If the socket is closed, the following message is delivered:</p>
<code type="none">
{tcp_closed, Socket}</code>
diff --git a/lib/kernel/doc/src/gen_udp.xml b/lib/kernel/doc/src/gen_udp.xml
index faca31e928..503725fe18 100644
--- a/lib/kernel/doc/src/gen_udp.xml
+++ b/lib/kernel/doc/src/gen_udp.xml
@@ -145,14 +145,23 @@
<seealso marker="inet#setopts/2">inet:setopts/2</seealso>.</p>
</item>
</taglist>
- <p>The returned socket <c><anno>Socket</anno></c> is used to send packets
- from this port with <c>send/4</c>. When UDP packets arrive at
- the opened port, they are delivered as messages:</p>
+ <p>The returned socket <c><anno>Socket</anno></c> is used to send
+ packets from this port with <c>send/4</c>. When UDP packets arrive
+ at the opened port, if the socket is in an active mode the packets
+ are delivered as messages to the controlling process:</p>
<code type="none">
{udp, Socket, IP, InPortNo, Packet}</code>
- <p>Note that arriving UDP packets that are longer than
+ <p>If the socket is not in an active mode, data can be
+ retrieved via the <seealso marker="#recv/2">recv/2,3</seealso> calls.
+ Note that arriving UDP packets that are longer than
the receive buffer option specifies, might be truncated
without warning.</p>
+ <p>When a socket in <c>{active, N}</c> mode (see <seealso marker="inet#setopts/2">
+ inet:setopts/2</seealso> for details) transitions to passive
+ (<c>{active, false}</c>) mode, the controlling process is notified by a
+ message of the following form:</p>
+ <code type="none">
+{udp_passive, Socket}</code>
<p><c>IP</c> and <c>InPortNo</c> define the address from which
<c>Packet</c> came. <c>Packet</c> is a list of bytes if
the option <c>list</c> was specified. <c>Packet</c> is a
diff --git a/lib/kernel/doc/src/inet.xml b/lib/kernel/doc/src/inet.xml
index 4a3796a15b..fb8bf32978 100644
--- a/lib/kernel/doc/src/inet.xml
+++ b/lib/kernel/doc/src/inet.xml
@@ -456,47 +456,66 @@ fe80::204:acff:fe17:bf38
<p>Sets one or more options for a socket. The following options
are available:</p>
<taglist>
- <tag><c>{active, true | false | once}</c></tag>
+ <tag><c>{active, true | false | once | N}</c></tag>
<item>
<p>If the value is <c>true</c>, which is the default,
everything received from the socket will be sent as
messages to the receiving process. If the value is
<c>false</c> (passive mode), the process must explicitly
- receive incoming data by calling <c>gen_tcp:recv/2,3</c>
- or <c>gen_udp:recv/2,3</c> (depending on the type of
- socket).</p>
+ receive incoming data by calling
+ <seealso marker="gen_tcp#recv/2"><c>gen_tcp:recv/2,3</c></seealso>,
+ <seealso marker="gen_udp#recv/2"><c>gen_udp:recv/2,3</c></seealso>
+ or <seealso marker="gen_sctp#recv/1"><c>gen_sctp:recv/1,2</c></seealso>
+ (depending on the type of socket).</p>
<p>If the value is <c>once</c> (<c>{active, once}</c>),
<em>one</em> data message from the socket will be sent
to the process. To receive one more message,
<c>setopts/2</c> must be called again with the
<c>{active, once}</c> option.</p>
- <p>When using <c>{active, once}</c>, the socket changes
- behaviour automatically when data is received. This can
- sometimes be confusing in combination with connection
- oriented sockets (i.e. <c>gen_tcp</c>) as a socket with
- <c>{active, false}</c> behaviour reports closing
+ <p>If the value is an integer <c>N</c> in the range -32768 to 32767
+ (inclusive), the value is added to the socket's count of data
+ messages sent to the controlling process. A socket's default
+ message count is 0. If a negative value is specified and its
+ magnitude is equal to or greater than the socket's current
+ message count, the socket's message count is set to 0. Once
+ the socket's message count reaches 0, either due to sending
+ received data messages to the process or by being explicitly set,
+ the process is then notified by a special message, specific to
+ the type of socket, that the socket has entered passive
+ mode. Once the socket enters passive mode, to receive more
+ messages <c>setopts/2</c> must be called again to set the
+ socket back into an active mode.</p>
+ <p>When using <c>{active, once}</c> or <c>{active, N}</c>, the
+ socket changes behaviour automatically when data is received.
+ This can sometimes be confusing in combination with
+ connection-oriented sockets (i.e. <c>gen_tcp</c>) as a socket
+ with <c>{active, false}</c> behaviour reports closing
differently than a socket with <c>{active, true}</c>
behaviour. To make programming easier, a socket where
the peer closed and this was detected while in
<c>{active, false}</c> mode, will still generate the
message
- <c>{tcp_closed,Socket}</c> when set to <c>{active, once}</c> or <c>{active, true}</c> mode. It is therefore
+ <c>{tcp_closed,Socket}</c> when set to <c>{active, once}</c>,
+ <c>{active, true}</c> or <c>{active, N}</c> mode. It is therefore
safe to assume that the message
<c>{tcp_closed,Socket}</c>, possibly followed by socket
port termination (depending on the <c>exit_on_close</c>
option) will eventually appear when a socket changes
back and forth between <c>{active, true}</c> and
- <c>{active, false}</c> mode. However,
+ <c>{active, false}</c> mode. However,
<em>when</em> peer closing is detected is all up to the
underlying TCP/IP stack and protocol.</p>
- <p>Note that <c>{active,true}</c> mode provides no flow
+ <p>Note that <c>{active, true}</c> mode provides no flow
control; a fast sender could easily overflow the
- receiver with incoming messages. Use active mode only if
+ receiver with incoming messages. The same is true of
+ <c>{active, N}</c> mode while the message count is greater
+ than zero. Use active mode only if
your high-level protocol provides its own flow control
(for instance, acknowledging received messages) or the
- amount of data exchanged is small. <c>{active,false}</c>
- mode or use of the <c>{active, once}</c> mode provides
- flow control; the other side will not be able send
+ amount of data exchanged is small. <c>{active, false}</c>
+ mode, use of the <c>{active, once}</c> mode or <c>{active, N}</c>
+ mode with values of <c>N</c> appropriate for the application
+ provides flow control; the other side will not be able send
faster than the receiver can read.</p>
</item>
@@ -722,6 +741,59 @@ fe80::204:acff:fe17:bf38
<p>Received <c>Packet</c> is delivered as defined by Mode.</p>
</item>
+ <tag><c>{netns, Namespace :: file:filename_all()}</c></tag>
+ <item>
+ <p>Set a network namespace for the socket. The <c>Namespace</c>
+ parameter is a filename defining the namespace for example
+ <c>"/var/run/netns/example"</c> typically created by the command
+ <c>ip netns add example</c>. This option must be used in a
+ function call that creates a socket i.e
+ <seealso marker="gen_tcp#connect/3">
+ gen_tcp:connect/3,4</seealso>,
+ <seealso marker="gen_tcp#listen/2">
+ gen_tcp:listen/2</seealso>,
+ <seealso marker="gen_udp#open/1">
+ gen_udp:open/1,2</seealso> or
+ <seealso marker="gen_sctp#open/0">
+ gen_sctp:open/0-2</seealso>.
+ </p>
+ <p>This option uses the Linux specific syscall
+ <c>setns()</c> such as in Linux kernel 3.0 or later
+ and therefore only exists when the runtime system
+ has been compiled for such an operating system.
+ </p>
+ <p>
+ The virtual machine also needs elevated privileges either
+ running as superuser or (for Linux) having the capability
+ <c>CAP_SYS_ADMIN</c> according to the documentation for setns(2).
+ However, during testing also <c>CAP_SYS_PTRACE</c>
+ and <c>CAP_DAC_READ_SEARCH</c> has proven to be necessary.
+ Example:<code>
+setcap cap_sys_admin,cap_sys_ptrace,cap_dac_read_search+epi beam.smp
+</code>
+ Note also that the filesystem containing the virtual machine
+ executable (<c>beam.smp</c> in the example above) has to be local,
+ mounted without the <c>nosetuid</c> flag,
+ support extended attributes and that
+ the kernel has to support file capabilities.
+ All this runs out of the box on at least Ubuntu 12.04 LTS,
+ except that SCTP sockets appears to not support
+ network namespaces.
+ </p>
+ <p>The <c>Namespace</c> is a file name and is encoded
+ and decoded as discussed in
+ <seealso marker="file">file</seealso>
+ except that the emulator flag <c>+fnu</c> is ignored and
+ <seealso marker="#getopts/2">getopts/2</seealso>
+ for this option will return a binary for the filename
+ if the stored filename can not be decoded,
+ which should only happen if you set the option using a binary
+ that can not be decoded with the emulator's filename encoding:
+ <seealso marker="file#native_name_encoding/0">
+ file:native_name_encoding/0</seealso>.
+ </p>
+ </item>
+
<tag><c>list</c></tag>
<item>
<p>Received <c>Packet</c> is delivered as a list.</p>
diff --git a/lib/kernel/doc/src/notes.xml b/lib/kernel/doc/src/notes.xml
index 6b703b7c2b..6cdc3a9d17 100644
--- a/lib/kernel/doc/src/notes.xml
+++ b/lib/kernel/doc/src/notes.xml
@@ -30,6 +30,66 @@
</header>
<p>This document describes the changes made to the Kernel application.</p>
+<section><title>Kernel 2.16.3</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fix indentation of User switch command help in Erlang
+ shell. Thanks to Sylvain Benner.</p>
+ <p>
+ Own Id: OTP-11209</p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>
+ The previous undocumented function ntoa/1 has been added
+ to inet docs and exported in the inet module.</p>
+ <p>
+ Own Id: OTP-10676 Aux Id: OTP-10314 </p>
+ </item>
+ <item>
+ <p>
+ Fix typo in abcast() function comment. Thanks to Johannes
+ Weissl.</p>
+ <p>
+ Own Id: OTP-11219</p>
+ </item>
+ <item>
+ <p>
+ Add application:ensure_all_started/1-2. Thanks to Fred
+ Hebert.</p>
+ <p>
+ Own Id: OTP-11250</p>
+ </item>
+ <item>
+ <p>
+ Make edlin understand a few important control keys.
+ Thanks to Stefan Zegenhagen.</p>
+ <p>
+ Own Id: OTP-11251</p>
+ </item>
+ <item>
+ <p>
+ Cleanup of hipe_unified_loader, eliminating uses of
+ is_subtype/2 in specs, change module-local void functions
+ to return 'ok' instead of [] and made sure there are no
+ dialyzer warnings with --Wunmatched_returns. Thanks to
+ Kostis Sagonas.</p>
+ <p>
+ Own Id: OTP-11301</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
<section><title>Kernel 2.16.2</title>
<section><title>Fixed Bugs and Malfunctions</title>