Log Message:
Update to Erlang/OTP R16B (designated as 16.1 in pkgsrc).

R16B is a major new release of Erlang/OTP.

Detailed information on changes can be fetched at
http://www.erlang.org/download/otp_src_R16B.readme

--- HIGHLIGHTS ----------------------------------------------------------

    OTP-7786  == ssh ==

	      Added User Guide for the SSH application

    OTP-9892  == erts ==

	      Process optimizations. The most notable:

	      -- New internal process table implementation allowing for
	      both parallel reads as well as writes. Especially read
	      operations have become really cheap. This reduce contention
	      in various situations. For example when, spawning processes,
	      terminating processes, sending messages, etc.

	      -- Optimizations of run queue management reducing contention.

	      -- Optimizations of process state changes reducing
	      contention.

	      These changes imply changes of the characteristics the
	      system. Most notable: changed timing in the system.

    OTP-9974  == erts ==

	      Non-blocking code loading. Earlier when an Erlang module was
	      loaded, all other execution in the VM were halted while the
	      load operation was carried out in single threaded mode. Now
	      modules are loaded without blocking the VM. Processes may
	      continue executing undisturbed in parallel during the entire
	      load operation. The load operation is completed by making the
	      loaded code visible to all processes in a consistent way with
	      one single atomic instruction. Non-blocking code loading will
	      improve realtime characteristics when modules are
	      loaded/upgraded on a running SMP system.

   OTP-10256  == inets ==

	      httpc: The HTTP client now supports HTTPS through proxies

   OTP-10336  == erts ==

	      Major port improvements. The most notable:

	      -- New internal port table implementation allowing for both
	      parallel reads as well as writes. Especially read operations
	      have become really cheap.This reduce contention in various
	      situations. For example when, creating ports, terminating
	      ports, etc.

	      -- Dynamic allocation of port structures. This allow for a
	      much larger maximum amount of ports allowed as a default. The
	      previous default of 1024 has been raised to 65536. Maximum
	      amount of ports can be set using the +Q command line flag of
	      erl(1). The previously used environment variable
	      ERL_MAX_PORTS has been deprecated and scheduled for removal
	      in OTP-R17.

	      -- Major rewrite of scheduling of port tasks. Major benefits
	      of the rewrite are reduced contention on run queue locks, and
	      reduced amount of memory allocation operations needed. The
	      rewrite was also necessary in order to make it possible to
	      schedule signals from processes to ports.

	      -- Improved internal thread progress functionality for easy
	      management of unmanaged threads. This improvement was
	      necessary for the rewrite of the port task scheduling.

	      -- Rewrite of all process to port signal implementations in
	      order to make it possible to schedule those operations. All
	      port operations can now be scheduled which allows for reduced
	      lock contention on the port lock as well as truly
	      asynchronous communication with ports.

	      -- Optimized lookup of port handles from drivers.

	      -- Optimized driver lookup when creating ports.

	      -- Preemptable erlang:ports/0 BIF.

	      -- Improving responsiveness by bumping reductions for a
	      process calling a driver callback directly.

	      These changes imply changes of the characteristics of the
	      system. The most notable:

	      -- Order of signal delivery -- The previous implementation of
	      the VM has delivered signals from processes to ports in a
	      synchronous stricter fashion than required by the language.
	      As of ERTS version 5.10, signals are truly asynchronously
	      delivered. The order of signal delivery still adheres to the
	      requirements of the language, but only to the requirements.
	      That is, some signal sequences that previously always were
	      delivered in one specific order may now from time to time be
	      delivered in different orders. This may cause Erlang programs
	      that have made false assumptions about signal delivery order
	      to fail even though they previously succeeded. For more
	      information about signal ordering guarantees, see the chapter
	      on communication in the ERTS user's guide. The +n command
	      line flag of erl(1) can be helpful when trying to find
	      signaling order bugs in Erlang code that have been exposed by
	      these changes.

	      -- Latency of signals sent from processes to ports -- Signals
	      from processes to ports where previously always delivered
	      immediately. This kept latency for such communication to a
	      minimum, but it could cause lock contention which was very
	      expensive for the system as a whole. In order to keep this
	      latency low also in the future, most signals from processes
	      to ports are by default still delivered immediately as long
	      as no conflicts occur. Such conflicts include not being able
	      to acquire the port lock, but also include other conflicts.
	      When a conflict occur, the signal will be scheduled for
	      delivery at a later time. A scheduled signal delivery may
	      cause a higher latency for this specific communication, but
	      improves the overall performance of the system since it
	      reduce lock contention between schedulers. The default
	      behavior of only scheduling delivery of these signals on
	      conflict can be changed by passing the +spp command line flag
	      to erl(1). The behavior can also be changed on port basis
	      using the parallelism option of the open_port/2 BIF.

	      -- Execution time of the erlang:ports/0 BIF -- Since
	      erlang:ports/0 now can be preempted, the responsiveness of
	      the system as a whole has been improved. A call to
	      erlang:ports/0 may, however, take a much longer time to
	      complete than before. How much longer time heavily depends on
	      the system load.

	      -- Reduction cost of calling driver callbacks -- Calling a
	      driver callback is quite costly. This was previously not
	      reflected in reduction cost at all. Since the reduction cost
	      now has increased, a process performing lots of direct driver
	      calls will be scheduled out more frequently than before.

	      Potential incompatibilities:

	      -- driver_send_term() has been deprecated and has been
	      scheduled for removal in OTP-R17. Replace usage of
	      driver_send_term() with usage of erl_drv_send_term().

	      -- driver_output_term() has been deprecated and has been
	      scheduled for removal in OTP-R17. Replace usage of
	      driver_output_term() with usage of erl_drv_output_term().

	      -- The new function erl_drv_busy_msgq_limits() has been added
	      in order to able to control management of port queues.

	      The driver API version has been bumped to 2.1 from 2.0 due to
	      the above changes in the driver API.

   OTP-10410  == asn1 ==

	      The options for the ASN.1 compiler has been drastically
	      simplified. The backend is chosen by using ber, per, or uper.
	      The options optimize, nif, and driver are no longer needed.
	      The old options will still work, but will issue a warning.

	      Another change is that generated encode/2 function will
	      always return a binary (some backends used to return an
	      iolist).

   OTP-10588  == asn1 ==

	      The ASN.1 compiler will now always include necessary run-time
	      functions in the generated Erlang modules (except for
	      asn1rt_nif which is still neeeded). If the option 'inline' is
	      used the ASN.1 compiler will generate a warning. But if
	      '{inline,OutputFile}' is use, the ASN.1 compiler will refuse
	      to compile the file. (Use a .set.asn file if you need to
	      remove the output file.)

	      The 'BIT STRING' type will now be decoded as Erlang
	      bitstrings by default. Use the new legacy_bit_string option
	      to encode as lists of ones and zeroes. (The
	      compact_bit_string option still works as before.)

	      Open types are now always returned as binaries (when there is
	      no information allowing them to be decoded).

--- POTENTIAL INCOMPATIBILITIES -----------------------------------------

    OTP-9052  == common_test ==

	      Removed depricated run_test program, use ct_run instead.

    OTP-9881  == common_test ==

	      It is now possible to let a test specification include other
	      test specifications. Included specs can either be joined with
	      the source spec (and all other joined specs), resulting in
	      one single test run, or they can be executed in separate test
	      runs. Also, a start flag/option, join_specs, has been
	      introduced, to be used in combination with the spec option.
	      With join_specs, Common Test can be told to either join
	      multiple test specifications, or run them separately. Without
	      join_specs, the latter behaviour is default. Note that this
	      is a change compared to earlier versions of Common Test,
	      where specifications could only be joined. More information
	      can be found in the Running Tests chapter in the User's Guide
	      (see the Test Specifications section).

   OTP-10117  == inviso ==

	      The inviso application has been removed.

   OTP-10170  == erts pman ==

	      Tuple funs (deprecated in R15B) are no longer supported.

   OTP-10195  == edoc ==

	      Since EDoc 0.7.7 (R14B02) separate values of union types can
	      be annotated. However, the parser has hitherto chosen not to
	      add the necessary parentheses due to backwards compatibility.

	      From this release on code traversing the output of
	      edoc_parser needs to take care of parentheses around separate
	      values of union types. Examples of such code are layout
	      modules and doclet modules.

   OTP-10336  == erts ==

	      Major port improvements. The most notable:

	      -- New internal port table implementation allowing for both
	      parallel reads as well as writes. Especially read operations
	      have become really cheap.This reduce contention in various
	      situations. For example when, creating ports, terminating
	      ports, etc.

	      -- Dynamic allocation of port structures. This allow for a
	      much larger maximum amount of ports allowed as a default. The
	      previous default of 1024 has been raised to 65536. Maximum
	      amount of ports can be set using the +Q command line flag of
	      erl(1). The previously used environment variable
	      ERL_MAX_PORTS has been deprecated and scheduled for removal
	      in OTP-R17.

	      -- Major rewrite of scheduling of port tasks. Major benefits
	      of the rewrite are reduced contention on run queue locks, and
	      reduced amount of memory allocation operations needed. The
	      rewrite was also necessary in order to make it possible to
	      schedule signals from processes to ports.

	      -- Improved internal thread progress functionality for easy
	      management of unmanaged threads. This improvement was
	      necessary for the rewrite of the port task scheduling.

	      -- Rewrite of all process to port signal implementations in
	      order to make it possible to schedule those operations. All
	      port operations can now be scheduled which allows for reduced
	      lock contention on the port lock as well as truly
	      asynchronous communication with ports.

	      -- Optimized lookup of port handles from drivers.

	      -- Optimized driver lookup when creating ports.

	      -- Preemptable erlang:ports/0 BIF.

	      -- Improving responsiveness by bumping reductions for a
	      process calling a driver callback directly.

	      These changes imply changes of the characteristics of the
	      system. The most notable:

	      -- Order of signal delivery -- The previous implementation of
	      the VM has delivered signals from processes to ports in a
	      synchronous stricter fashion than required by the language.
	      As of ERTS version 5.10, signals are truly asynchronously
	      delivered. The order of signal delivery still adheres to the
	      requirements of the language, but only to the requirements.
	      That is, some signal sequences that previously always were
	      delivered in one specific order may now from time to time be
	      delivered in different orders. This may cause Erlang programs
	      that have made false assumptions about signal delivery order
	      to fail even though they previously succeeded. For more
	      information about signal ordering guarantees, see the chapter
	      on communication in the ERTS user's guide. The +n command
	      line flag of erl(1) can be helpful when trying to find
	      signaling order bugs in Erlang code that have been exposed by
	      these changes.

	      -- Latency of signals sent from processes to ports -- Signals
	      from processes to ports where previously always delivered
	      immediately. This kept latency for such communication to a
	      minimum, but it could cause lock contention which was very
	      expensive for the system as a whole. In order to keep this
	      latency low also in the future, most signals from processes
	      to ports are by default still delivered immediately as long
	      as no conflicts occur. Such conflicts include not being able
	      to acquire the port lock, but also include other conflicts.
	      When a conflict occur, the signal will be scheduled for
	      delivery at a later time. A scheduled signal delivery may
	      cause a higher latency for this specific communication, but
	      improves the overall performance of the system since it
	      reduce lock contention between schedulers. The default
	      behavior of only scheduling delivery of these signals on
	      conflict can be changed by passing the +spp command line flag
	      to erl(1). The behavior can also be changed on port basis
	      using the parallelism option of the open_port/2 BIF.

	      -- Execution time of the erlang:ports/0 BIF -- Since
	      erlang:ports/0 now can be preempted, the responsiveness of
	      the system as a whole has been improved. A call to
	      erlang:ports/0 may, however, take a much longer time to
	      complete than before. How much longer time heavily depends on
	      the system load.

	      -- Reduction cost of calling driver callbacks -- Calling a
	      driver callback is quite costly. This was previously not
	      reflected in reduction cost at all. Since the reduction cost
	      now has increased, a process performing lots of direct driver
	      calls will be scheduled out more frequently than before.

	      Potential incompatibilities:

	      -- driver_send_term() has been deprecated and has been
	      scheduled for removal in OTP-R17. Replace usage of
	      driver_send_term() with usage of erl_drv_send_term().

	      -- driver_output_term() has been deprecated and has been
	      scheduled for removal in OTP-R17. Replace usage of
	      driver_output_term() with usage of erl_drv_output_term().

	      -- The new function erl_drv_busy_msgq_limits() has been added
	      in order to able to control management of port queues.

	      The driver API version has been bumped to 2.1 from 2.0 due to
	      the above changes in the driver API.

   OTP-10410  == asn1 ==

	      The options for the ASN.1 compiler has been drastically
	      simplified. The backend is chosen by using ber, per, or uper.
	      The options optimize, nif, and driver are no longer needed.
	      The old options will still work, but will issue a warning.

	      Another change is that generated encode/2 function will
	      always return a binary (some backends used to return an
	      iolist).

   OTP-10417  == kernel sasl ==

	      It is no longer possible to have {Mod,Vsn} in the 'modules'
	      list in a .app file.

	      This was earlier possible, although never documented in the
	      .app file reference manual. It was however visible in the
	      documentation of application:load/[1,2], where the same term
	      as in a .app file can be used as the first argument.

	      The possibility has been removed since the Vsn part was never
	      used.

   OTP-10451  == ssl ==

	      Remove filter mechanisms that made error messages backwards
	      compatible with old ssl but hid information about what
	      actually happened.

	      This does not break the documented API however other reason
	      terms may be returned, so code that matches on the reason
	      part of {error, Reason} may fail.

   OTP-10490  == stdlib ==

	      If a child process fails in its start function, then the
	      error reason was earlier only reported as an error report
	      from the error_handler, and supervisor:start_link would only
	      return {error,shutdown}. This has been changed so the
	      supervisor will now return {error,{shutdown,Reason}}, where
	      Reason identifies the failing child and its error reason.
	      (Thanks to Tomas Pihl)

   OTP-10523  == tools ==

	      A new function, cover:flush(Nodes), is added which will fetch
	      data from remote nodes without stopping cover on those nodes.
	      This is used by test_server and common_test when it is safe
	      to assume that the node will be terminated after the test
	      anyway. The purpose is to avoid processes crashing when
	      re-loading the original beam if the processes is still
	      running old code.

	      Remote nodes will now continue to count code coverage if the
	      connection to the main node is broken. Earlier, a broken
	      connection would cause the cover_server on the remote node to
	      die and thus any still cover compiled modules would cause
	      process crash when trying to insert cover data in ets tables
	      that used to exist on the cover_server. The new functionality
	      also involves synchronization with the main node if the nodes
	      are reconnected.

   OTP-10588  == asn1 ==

	      The ASN.1 compiler will now always include necessary run-time
	      functions in the generated Erlang modules (except for
	      asn1rt_nif which is still neeeded). If the option 'inline' is
	      used the ASN.1 compiler will generate a warning. But if
	      '{inline,OutputFile}' is use, the ASN.1 compiler will refuse
	      to compile the file. (Use a .set.asn file if you need to
	      remove the output file.)

	      The 'BIT STRING' type will now be decoded as Erlang
	      bitstrings by default. Use the new legacy_bit_string option
	      to encode as lists of ones and zeroes. (The
	      compact_bit_string option still works as before.)

	      Open types are now always returned as binaries (when there is
	      no information allowing them to be decoded).

   OTP-10613  == ssl ==

	      Removed deprecated function ssl:pid/0, it has been pointless
	      since R14 but has been keep for backwards compatibility.

   OTP-10633  == erts ==

	      Erlang specification 4.7.3 defines max tuple size to 65535
	      elements It is now enforced to no more than 16777215 elements
	      (arity 24 bits)

	      Previous edge cases (28 bits) were not validated and could
	      cause undefined behaviour.

   OTP-10647  == erts ==

	      The previous default of a maximum of 32768 simultaneous
	      processes has been raised to 262144. This value can be
	      changed using the the +P command line flag of erl(1). Note
	      that the value passed now is considered as a hint, and that
	      actual value chosen in most cases will be a power of two.

   OTP-10812  == stdlib ==

	      filelib:wildcard("some/relative/path/*.beam", Path) would
	      fail to match any file. That is, filelib:wildcard/2 would not
	      work if the first component of the pattern did not contain
	      any wildcard characters. (A previous attempt to fix the
	      problem in R15B02 seems to have made matters worse.)

	      (Thanks to Samuel Rivas and Tuncer Ayaz.)

	      There is also an incompatible change to the Path argument. It
	      is no longer allowed to be a binary.

   OTP-10872  == erts ==

	      As of ERTS-5.10/OTP-R16A node names passed in the EPMD
	      protocol are required to be encoded in UTF-8. Since EPMD
	      previously accepted latin1 encoded node names this is an
	      incompatibility. However, since Erlang nodes always have
	      required characters in node names to be 7-bit ASCII
	      characters (and still do require this), this incompatibility
	      should not effect anyone using EPMD as an Erlang Port Mapper
	      Daemon.