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diff --git a/lib/stdlib/doc/src/notes.xml b/lib/stdlib/doc/src/notes.xml
index bb35224182..2bea75ef9f 100644
--- a/lib/stdlib/doc/src/notes.xml
+++ b/lib/stdlib/doc/src/notes.xml
@@ -4,7 +4,7 @@
<chapter>
<header>
<copyright>
- <year>2004</year><year>2016</year>
+ <year>2004</year><year>2018</year>
<holder>Ericsson AB. All Rights Reserved.</holder>
</copyright>
<legalnotice>
@@ -31,6 +31,1566 @@
</header>
<p>This document describes the changes made to the STDLIB application.</p>
+<section><title>STDLIB 3.9.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p> Fix a bug that could cause a failure when formatting
+ binaries using the control sequences <c>p</c> or <c>P</c>
+ and limiting the output with the option
+ <c>chars_limit</c>. </p>
+ <p>
+ Own Id: OTP-15847 Aux Id: ERL-957 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>STDLIB 3.9</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p> Fix a bug in <c>string:lexemes/2</c>. </p> <p> The
+ bug was found when optimizing the handling of deep lists
+ of Unicode characters in the <c>string</c> module. </p>
+ <p>
+ Own Id: OTP-15649</p>
+ </item>
+ <item>
+ <p>A bug has been fixed in the <c>maps</c> implementation
+ that could cause a crash or memory usage to grow until
+ the machine ran out of memory. This could happen when
+ inserting a new key-value pair with a key <c>K1</c>
+ containing a binary <c>B1</c> into a map <c>M</c> having
+ a key <c>K2</c> with a binary <c>B2</c> if the following
+ conditions were met:</p> <list> <item><c>B1 =/=
+ B2</c></item> <item><c>size(B1) >= 4294967296</c></item>
+ <item><c>size(B2) >= 4294967296</c></item>
+ <item><c>size(M) >= 32</c></item> <item><c>(size(B1) rem
+ 4294967296) == (size(B2) rem 4294967296)</c></item>
+ <item>the first <c>(size(B1) rem 4294967296)</c> bytes
+ are the same both in <c>B1</c> and <c>B2</c></item>
+ <item>substituting <c>B1</c> in <c>K1</c> with <c>B2</c>
+ would create a term with the same value as
+ <c>K2</c></item> </list> <p>The root cause of the problem
+ is that the <c>maps</c> implementation only hashed the
+ first <c>(X rem 4294967296)</c> bytes of binaries so that
+ different binaries could get the same hash value
+ independently of the hash seed.</p>
+ <p>
+ Own Id: OTP-15707</p>
+ </item>
+ <item>
+ <p> Since the introduction of the stack trace variable,
+ the Erlang Pretty Printer has left out the exception
+ class <c>throw</c> even when the stack trace variable
+ cannot be left out, which is not correct Erlang code. The
+ fix is to always include the exception class
+ <c>throw</c>. </p>
+ <p>
+ Own Id: OTP-15751</p>
+ </item>
+ <item>
+ <p><c>record_info/2</c> is a pseudo-function that
+ requires literal arguments known at compile time.
+ Therefore, the following usage is illegal: <c>fun
+ record/info/2</c>. The compiler would crash when during
+ compilation of that kind of code. Corrected to issue a
+ compilation error.</p>
+ <p>
+ Own Id: OTP-15760 Aux Id: ERL-907 </p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p> A new <c>rand</c> module algorithm, <c>exro928ss</c>
+ (Xoroshiro928**), has been implemented. It has got a
+ really long period and good statistical quality for all
+ output bits, while still being only about 50% slower than
+ the default algorithm. </p><p> The same generator is also
+ used as a long period counter in a new <c>crypto</c>
+ plugin for the <c>rand</c> module, algorithm
+ <c>crypto_aes</c>. This plugin uses AES-256 to scramble
+ the counter which buries any detectable statistical
+ artifacts. Scrambling is done in chunks which are cached
+ to get good amortized speed (about half of the default
+ algorithm). </p>
+ <p>
+ Own Id: OTP-14461 Aux Id: PR-1857 </p>
+ </item>
+ <item>
+ <p>
+ Types related to server naming and starting have been
+ exported from <c>gen_statem</c>. These are:
+ <c>server_name/0</c>, <c>server_ref/0</c>,
+ <c>start_opt/0</c>, <c>start_ret/0</c> and
+ <c>enter_loop_opt/0</c>.</p>
+ <p>
+ Own Id: OTP-14724 Aux Id: PR-2056 </p>
+ </item>
+ <item>
+ <p>
+ The default algorithm for the <c>rand</c> module has been
+ changed to <c>exsss</c> (Xorshift116**) which is a
+ combination of the Xorshift116 (<c>exsp</c>) state update
+ and a new scrambler "StarStar" from the 2018 paper
+ "Scrambled Linear Pseudorandom Number Generators" by
+ David Blackman and Sebastiano Vigna. This combination
+ should not have the caveat of weak low bits that the
+ previous default algorithm(s) have had, with the cost of
+ about 10% lower speed. See GitHub pull request #1969.</p>
+ <p>
+ Own Id: OTP-14731 Aux Id: PR-1969 </p>
+ </item>
+ <item>
+ <p>
+ The generic state machine behaviour <c>gen_statem</c> has
+ gotten code cleanup and documentation improvements from
+ GitHub Pull Request #1855, even though the PR itself was
+ rejected.</p>
+ <p>
+ Own Id: OTP-14737 Aux Id: PR-1855 </p>
+ </item>
+ <item>
+ <p>
+ Update Unicode specification to version 11.0.</p>
+ <p>
+ Own Id: OTP-15111</p>
+ </item>
+ <item>
+ <p>
+ ETS option <c>write_concurrency</c> now also affects and
+ improves the scalability of <c>ordered_set</c> tables.
+ The implementation is based on a data structure called
+ contention adapting search tree, where the lock
+ granularity adapts to the actual amount of concurrency
+ exploited by the applications in runtime.</p>
+ <p>
+ Own Id: OTP-15128</p>
+ </item>
+ <item>
+ <p>
+ Optimized <c>maps:new/0</c> with trivial Erlang
+ implementation, making use of literal terms (the empty
+ map) not needing dynamic heap allocation.</p>
+ <p>
+ Own Id: OTP-15200 Aux Id: PR-1878 </p>
+ </item>
+ <item>
+ <p>The <c>gen_*</c> behaviours have been changed so that
+ if logging of the last N messages through
+ <c>sys:log/2,3</c> is active for the server, this log is
+ included in the terminate report.</p> <p>To accomplish
+ this the format of "System Events" as defined in the man
+ page for <c>sys</c> has been clarified and cleaned up, a
+ new function <c>sys:get_log/1</c> has been added, and
+ <c>sys:get_debug/3</c> has been deprecated. Due to these
+ changes, code that relies on the internal badly
+ documented format of "System Events", need to be
+ corrected.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-15381</p>
+ </item>
+ <item>
+ <p>
+ The <c>gen_statem</c> behaviour engine loop has been
+ optimized for better performance in particular when the
+ callback module returns some actions, that is better
+ performance for more realistic applications than the Echo
+ Benchmark.</p>
+ <p>
+ Own Id: OTP-15452</p>
+ </item>
+ <item>
+ <p> Do not allow function specifications for functions
+ residing in other modules. </p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-15563 Aux Id: ERL-845, OTP-15562 </p>
+ </item>
+ <item>
+ <p>
+ The <c>persistent_term</c> functions <c>put/2</c> and
+ <c>erase/1</c> are now yielding.</p>
+ <p>
+ Own Id: OTP-15615</p>
+ </item>
+ <item>
+ <p>Previously, all ETS tables used centralized counter
+ variables to keep track of the number of items stored and
+ the amount of memory consumed. These counters can cause
+ scalability problems (especially on big NUMA systems).
+ This change adds an implementation of a decentralized
+ counter and modifies the implementation of ETS so that
+ ETS tables of type <c>ordered_set</c> with
+ <c>write_concurrency</c> enabled use the decentralized
+ counter. Experiments indicate that this change
+ substantially improves the scalability of ETS
+ <c>ordered_set</c> tables with <c>write_concurrency</c>
+ enabled in scenarios with frequent <c>ets:insert/2</c>
+ and <c>ets:delete/2</c> calls.</p>
+ <p>
+ Own Id: OTP-15623 Aux Id: PR-2190 </p>
+ </item>
+ <item>
+ <p> Use <c>ssh</c> instead of <c>rsh</c> as the default
+ remote shell. </p>
+ <p>
+ Own Id: OTP-15633 Aux Id: PR-1787 </p>
+ </item>
+ <item>
+ <p>Added <c>beam_lib:strip/2</c> and friends, which
+ accept a list of chunks that should be preserved when
+ stripping.</p>
+ <p>
+ Own Id: OTP-15680 Aux Id: PR-2114 </p>
+ </item>
+ <item>
+ <p> Optimize printing of maps with <c>io_lib:write()</c>.
+ Also optimize pretty printing of strings (<c>~s</c> and
+ <c>~ts</c>) when limiting the output with the
+ <c>chars_limit</c> option. </p>
+ <p>
+ Own Id: OTP-15705</p>
+ </item>
+ <item>
+ <p> There are new compiler options <c>nowarn_removed</c>
+ and <c>{nowarn_removed,Items}</c> to suppress warnings
+ for functions and modules that have been removed from
+ OTP.</p>
+ <p>
+ Own Id: OTP-15749 Aux Id: ERL-904 </p>
+ </item>
+ <item>
+ <p> Let the Erlang Pretty Printer put atomic parts on the
+ same line. </p>
+ <p>
+ Own Id: OTP-15755</p>
+ </item>
+ <item>
+ <p> Add option <c>quote_singleton_atom_types</c> to the
+ Erlang Pretty Printer's functions. Setting the option to
+ <c>true</c> adds quotes to all singleton atom types. </p>
+ <p>
+ Own Id: OTP-15756</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>STDLIB 3.8.2.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p> Fix a bug that could cause a failure when formatting
+ binaries using the control sequences <c>p</c> or <c>P</c>
+ and limiting the output with the option
+ <c>chars_limit</c>. </p>
+ <p>
+ Own Id: OTP-15847 Aux Id: ERL-957 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>STDLIB 3.8.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ A bug in gen_statem has been fixed where the internal
+ timeout message could arrive as an info to the callback
+ module during high load due to incorrect use of
+ asynchronous timer cancel.</p>
+ <p>
+ Own Id: OTP-15295</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>STDLIB 3.8.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Fixed a performance regression when reading files
+ opened with the <c>compressed</c> flag.</p>
+ <p>
+ Own Id: OTP-15706 Aux Id: ERIERL-336 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>STDLIB 3.8</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p> Fix a bug in the Erlang Pretty Printer: long atom
+ names in combination with <c>&lt;&lt;&gt;&gt;</c> could
+ cause a crash. </p>
+ <p>
+ Own Id: OTP-15592 Aux Id: ERL-818 </p>
+ </item>
+ <item>
+ <p> Fix bugs that could cause wrong results or bad
+ performance when formatting lists of characters using the
+ control sequences <c>p</c> or <c>P</c> and limiting the
+ output with the option <c>chars_limit</c>. </p>
+ <p>
+ Own Id: OTP-15639</p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>
+ Improved ETS documentation about safe table traversal and
+ the partially bound key optimization for
+ <c>ordered_set</c>.</p>
+ <p>
+ Own Id: OTP-15545 Aux Id: PR-2103, PR-2139 </p>
+ </item>
+ <item>
+ <p> Optimize <c>calendar:gregorian_days_to_date/1</c>.
+ </p>
+ <p>
+ Own Id: OTP-15572 Aux Id: PR-2121 </p>
+ </item>
+ <item>
+ <p> Optimize functions
+ <c>calendar:rfc3339_to_system_time()</c> and
+ <c>calendar:system_time_to_rfc3339()</c>. </p>
+ <p>
+ Own Id: OTP-15630</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>STDLIB 3.7.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p> Optimize pretty printing of terms. The slower
+ behaviour was introduced in Erlang/OTP 20. </p>
+ <p>
+ Own Id: OTP-15573 Aux Id: ERIERL-306 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>STDLIB 3.7</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Document <c>bit_size</c> in match specifications and
+ allow it in <c>ets:fun2ms</c>.</p>
+ <p>
+ Own Id: OTP-15343 Aux Id: PR-1962 </p>
+ </item>
+ <item>
+ <p>The <c>beam()</c> type in <c>beam_lib</c> is defined
+ as <c>module() | file:filename() | binary()</c>. The
+ <c>module()</c> is misleading. Giving the module name as
+ an atom will only work if the BEAM file is in a current
+ directory.</p>
+ <p>To avoid confusion, <c>module()</c> has been removed
+ from the type. That means that there will be a Dialyzer
+ warning for code that call <c>beam_lib</c> with an atom
+ as filename, but the calls will still work.</p>
+ <p>
+ Own Id: OTP-15378 Aux Id: ERL-696 </p>
+ </item>
+ <item>
+ <p>
+ <c>unicode_util</c> crashed on certain emoji grapheme
+ clusters in binary strings.</p>
+ <p>
+ Own Id: OTP-15428 Aux Id: ERL-777 </p>
+ </item>
+ <item>
+ <p>When an external fun was used, warnings for unused
+ variables could be suppressed.</p>
+ <p>
+ Own Id: OTP-15437 Aux Id: ERL-762 </p>
+ </item>
+ <item>
+ <p>
+ Fix reduction count in lists:member/2</p>
+ <p>
+ Own Id: OTP-15474 Aux Id: ERIERL-229 </p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>When specified, the <c>+{source,Name}</c> option will
+ now override the actual file name in stack traces,
+ instead of only affecting the return value of
+ <c>Mod:module_info()</c>.</p>
+ <p>The <c>+deterministic</c> flag will also affect stack
+ traces now, omitting all path information except the file
+ name, fixing a long-standing issue where deterministic
+ builds required deterministic paths.</p>
+ <p>
+ Own Id: OTP-15245 Aux Id: ERL-706 </p>
+ </item>
+ <item>
+ <p>List subtraction (The <c>--</c> operator) will now
+ yield properly on large inputs.</p>
+ <p>
+ Own Id: OTP-15371</p>
+ </item>
+ <item>
+ <p>
+ <c>calendar:system_time_to_rfc3339/1,2</c> no longer
+ remove trailing zeros from fractions.</p>
+ <p>
+ Own Id: OTP-15464</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>STDLIB 3.6</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>The specs of <c>filename:basedir/2,3</c> are
+ corrected.</p>
+ <p>
+ Own Id: OTP-15252 Aux Id: ERL-667 </p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p> Let <c>dets:open_file()</c> exit with a <c>badarg</c>
+ message if given a raw file name (a binary). </p>
+ <p>
+ Own Id: OTP-15253 Aux Id: OTP-13229, ERL-55 </p>
+ </item>
+ <item>
+ <p> The <c>Format</c> argument of the formatting
+ functions in modules <c>io</c> and <c>io_lib</c> is
+ accepted even if it is, for example, a list of binaries.
+ This is how it used to be before Erlang/OTP 21.0. </p>
+ <p>
+ Own Id: OTP-15304</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>STDLIB 3.5.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p> Fix a bug that could cause a crash when formatting a
+ list of non-characters using the control sequences
+ <c>p</c> or <c>P</c> and limiting the output with the
+ option <c>chars_limit</c>. </p>
+ <p>
+ Own Id: OTP-15159</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>STDLIB 3.5</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p><c>gen_statem</c> improvements.</p> <p> When using an
+ exception that is valid but not allowed in a state enter
+ call, the reason has been changed from
+ <c>{bad_action_from_state_function,Action}</c> to
+ <c>{bad_state_enter_action_from_state_function,Action}</c>.
+ </p><p> Timer parsing has been improved. Many erroneous
+ timeout tuples was not handled correctly. </p><p> The
+ documentation has been updated, in particular the User's
+ Guide and the pointer to it from the Reference Manual is
+ much more obvious. </p>
+ <p>
+ Own Id: OTP-14015</p>
+ </item>
+ <item>
+ <p>
+ The type specifications for <c>file:posix/0</c> and
+ <c>inet:posix/0</c> have been updated according to which
+ errors file and socket operations should be able to
+ return.</p>
+ <p>
+ Own Id: OTP-14019 Aux Id: ERL-550 </p>
+ </item>
+ <item>
+ <p> File operations used to accept <seealso
+ marker="kernel:file#type-name_all">filenames</seealso>
+ containing null characters (integer value zero). This
+ caused the name to be truncated and in some cases
+ arguments to primitive operations to be mixed up.
+ Filenames containing null characters inside the filename
+ are now <em>rejected</em> and will cause primitive file
+ operations to fail. </p> <p> Also environment variable
+ operations used to accept <seealso
+ marker="kernel:os#type-env_var_name">names</seealso> and
+ <seealso
+ marker="kernel:os#type-env_var_value">values</seealso> of
+ environment variables containing null characters (integer
+ value zero). This caused operations to silently produce
+ erroneous results. Environment variable names and values
+ containing null characters inside the name or value are
+ now <em>rejected</em> and will cause environment variable
+ operations to fail. </p> <p>Primitive environment
+ variable operations also used to accept the <c>$=</c>
+ character in environment variable names causing various
+ problems. <c>$=</c> characters in environment variable
+ names are now also <em>rejected</em>. </p> <p>Also
+ <seealso
+ marker="kernel:os#cmd/1"><c>os:cmd/1</c></seealso> now
+ reject null characters inside its <seealso
+ marker="kernel:os#type-os_command">command</seealso>.
+ </p> <p><seealso
+ marker="erts:erlang#open_port/2"><c>erlang:open_port/2</c></seealso>
+ will also reject null characters inside the port name
+ from now on.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14543 Aux Id: ERL-370 </p>
+ </item>
+ <item>
+ <p> Make <c>io_lib:unscan_format/1</c> work with pad char
+ and default precision. </p>
+ <p>
+ Own Id: OTP-14958 Aux Id: PR-1735 </p>
+ </item>
+ <item>
+ <p> The control sequence modifiers <c>t</c> and <c>l</c>
+ can be used together in the same control sequence which
+ makes it possible to have Unicode atoms and no detection
+ of printable character lists at the same time. </p>
+ <p>
+ Own Id: OTP-14971 Aux Id: PR-1743 </p>
+ </item>
+ <item>
+ <p> Fix a bug in the Erlang code linter: the check of
+ guard expressions no longer returns <c>false</c> if the
+ map syntax is used. The bug affected the Erlang shell,
+ the Debugger, and other modules evaluating abstract code.
+ </p>
+ <p>
+ Own Id: OTP-15035 Aux Id: ERL-613 </p>
+ </item>
+ <item>
+ <p>
+ A sys debug fun of type {Fun,State} should not be
+ possible to install twice. This was, however, possible if
+ the current State was 'undefined', which was mistaken for
+ non-existing fun. This has been corrected.</p>
+ <p>
+ Own Id: OTP-15049</p>
+ </item>
+ <item>
+ <p>
+ Fix <c>io:putchars/2</c> stacktrace rewriting at errors
+ to point to a valid function.</p>
+ <p>
+ Own Id: OTP-15101</p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>
+ The <c>gen_server</c> has gotten a new callback
+ <c>handle_continue/2</c> for check pointing the state.
+ This is useful at least when implementing behaviours on
+ top of <c>gen_server</c> and for some start up scenarios.</p>
+ <p>
+ Own Id: OTP-13019 Aux Id: PR-1490 </p>
+ </item>
+ <item>
+ <p> The semantics of timeout parameter
+ <c>{clean_timeout,infinity}</c> to
+ <c>gen_statem:call/3</c> has been changed to use a proxy
+ process for the call. With this change
+ <c>clean_timeout</c> implicates a proxy process with no
+ exceptions. This may be a hard to observe
+ incompatibility: in the presence of network problems a
+ late reply could arrive in the caller's message queue
+ when catching errors. That will not happen after this
+ correction. </p><p> The semantics of timeout parameter
+ <c>infinity</c> has not been changed. </p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-13073 Aux Id: PR-1595 </p>
+ </item>
+ <item>
+ <p>A new logging API is added to Erlang/OTP, see the
+ <seealso
+ marker="kernel:logger"><c>logger(3)</c></seealso> manual
+ page, and section <seealso
+ marker="kernel:logger_chapter">Logging</seealso> in the
+ Kernel User's Guide.</p>
+ <p>Calls to <c>error_logger</c> are automatically
+ redirected to the new API, and legacy error logger event
+ handlers can still be used. It is, however, recommended
+ to use the Logger API directly when writing new code.</p>
+ <p>Notice the following potential incompatibilities:</p>
+ <list> <item><p>Kernel configuration parameters
+ <c>error_logger</c> still works, but is overruled if the
+ default handler's output destination is configured with
+ Kernel configuration parameter <c>logger</c>.</p> <p>In
+ general, parameters for configuring error logger are
+ overwritten by new parameters for configuring
+ Logger.</p></item> <item><p>The concept of SASL error
+ logging is deprecated, meaning that by default the SASL
+ application does not affect which log events are
+ logged.</p> <p>By default, supervisor reports and crash
+ reports are logged by the default Logger handler started
+ by Kernel, and end up at the same destination (terminal
+ or file) as other standard log event from Erlang/OTP.</p>
+ <p>Progress reports are not logged by default, but can be
+ enabled by setting the primary log level to info, for
+ example with the Kernel configuration parameter
+ <c>logger_level</c>.</p> <p>To obtain backwards
+ compatibility with the SASL error logging functionality
+ from earlier releases, set Kernel configuration parameter
+ <c>logger_sasl_compatible</c> to <c>true</c>. This
+ prevents the default Logger handler from logging any
+ supervisor-, crash-, or progress reports. Instead, SASL
+ adds a separate Logger handler during application start,
+ which takes care of these log events. The SASL
+ configuration parameters <c>sasl_error_logger</c> and
+ <c>sasl_errlog_type</c> specify the destination (terminal
+ or file) and severity level to log for these
+ events.</p></item></list>
+ <p>
+ Since Logger is new in Erlang/OTP 21.0, we do reserve the
+ right to introduce changes to the Logger API and
+ functionality in patches following this release. These
+ changes might or might not be backwards compatible with
+ the initial version.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-13295</p>
+ </item>
+ <item>
+ <p> Add functions
+ <c>calendar:system_time_to_local_time/2</c> and
+ <c>calendar:system_time_to_universal_time/2</c>. </p>
+ <p>
+ Own Id: OTP-13413</p>
+ </item>
+ <item>
+ <p> Functions <c>rand:uniform_real/0</c> and
+ <c>rand:uniform_real_s/1</c> have been added. They
+ produce uniformly distributed numbers in the range <c>0.0
+ =&lt; X &lt; 1.0</c> that are as close to random real
+ numbers as Normalized IEEE 754 Double Precision allows.
+ Because the random real number exactly <c>0.0</c> is
+ infinitely improbable they will never return exactly
+ <c>0.0</c>. </p><p> These properties are useful when you
+ need to call for example <c>math:log(X)</c> or <c>1 /
+ X</c> on a random value <c>X</c>, since that will never
+ fail with a number from these new functions. </p>
+ <p>
+ Own Id: OTP-13764 Aux Id: PR-1574 </p>
+ </item>
+ <item>
+ <p>
+ Added maps:iterator/0 and maps:next/1 to be used for
+ iterating over the key-value associations in a map.</p>
+ <p>
+ Own Id: OTP-14012</p>
+ </item>
+ <item>
+ <p>Changed the default behaviour of <c>.erlang</c>
+ loading: <c>.erlang</c> is no longer loaded from the
+ current directory. <c>c:erlangrc(PathList)</c> can be
+ used to search and load an <c>.erlang</c> file from user
+ specified directories.</p> <p><c>escript</c>,
+ <c>erlc</c>, <c>dialyzer</c> and <c>typer</c> no longer
+ load an <c>.erlang</c> at all.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14439</p>
+ </item>
+ <item>
+ <p>
+ Added new uri_string module to stdlib for handling URIs
+ (RFC 3986).</p>
+ <p>
+ Own Id: OTP-14496</p>
+ </item>
+ <item>
+ <p>
+ Update Unicode specification to version 10.0.</p>
+ <p>
+ Own Id: OTP-14503</p>
+ </item>
+ <item>
+ <p><c>filelib:wildcard()</c> now allows characters with a
+ special meaning to be escaped using backslashes.</p>
+ <p>This is an incompatible change, but note that the use
+ of backslashes in wildcards would already work
+ differently on Windows and Unix. Existing calls to
+ <c>filelib:wildcard()</c> needs to be updated. On
+ Windows, directory separators must always be written as a
+ slash.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14577</p>
+ </item>
+ <item>
+ <p>
+ The supervisor now stores its child specifications in a
+ map instead of a list. This causes a significant
+ improvement when starting many children under a
+ non-simple_one_for_one supervisor.</p>
+ <p>
+ Own Id: OTP-14586</p>
+ </item>
+ <item>
+ <p> The <c>base64</c> module is optimized. </p> <p> Note
+ that the functions <c>encode/1</c>, <c>decode/1</c>, and
+ <c>mime_decode/1</c> fail unless called with an argument
+ of the documented type. They used to accept any
+ <c>iodata()</c>. </p>
+ <p>
+ Own Id: OTP-14624 Aux Id: PR-1565 </p>
+ </item>
+ <item>
+ <p> Add function <c>lists:search/2</c>. </p>
+ <p>
+ Own Id: OTP-14675 Aux Id: PR-102 </p>
+ </item>
+ <item>
+ <p>
+ uri_string module extended with functions for handling
+ application/x-www-form-urlencoded query strings based on
+ the HTML5 specification.</p>
+ <p>
+ Own Id: OTP-14747</p>
+ </item>
+ <item>
+ <p> Add functions
+ <c>calendar:rfc3339_to_system_time/1,2</c> and
+ <c>calendar:system_time_to_rfc3339/1,2</c>. </p>
+ <p>
+ Own Id: OTP-14764</p>
+ </item>
+ <item>
+ <p> The stack traces returned by the functions of the
+ <c>erl_eval</c> module more accurately reflect where the
+ exception occurred. </p>
+ <p>
+ Own Id: OTP-14826 Aux Id: PR 1540 </p>
+ </item>
+ <item>
+ <p> Add options <c>atime</c>, <c>mtime</c>, <c>ctime</c>,
+ <c>uid</c>, and <c>gid</c> to the <c>erl_tar:add/3,4</c>
+ functions. </p>
+ <p>
+ Own Id: OTP-14834 Aux Id: PR 1608 </p>
+ </item>
+ <item>
+ <p>Added <c>ets:whereis/1</c> for retrieving the table
+ identifier of a named table.</p>
+ <p>
+ Own Id: OTP-14884</p>
+ </item>
+ <item>
+ <p>
+ Improved URI normalization functions in the uri_string
+ module.</p>
+ <p>
+ Own Id: OTP-14910</p>
+ </item>
+ <item>
+ <p> The new functions <c>io_lib:fwrite/3</c> and
+ <c>io_lib:format/3</c> take a third argument, an option
+ list. The only option is <c>chars_limit</c>, which is
+ used for limiting the number of returned characters. The
+ limit is soft, which means that the number of returned
+ characters exceeds the limit with at most a smallish
+ amount. If the limit is set, the functions
+ <c>format/3</c> and <c>fwrite/3</c> try to distribute the
+ number of characters evenly over the control sequences
+ <c>pPswW</c>. Furthermore, the control sequences
+ <c>pPwP</c> try to distribute the number of characters
+ evenly over substructures. </p> <p> A modification of the
+ control sequences <c>pPwW</c> is that even if there is no
+ limit on the number of returned characters, all
+ associations of a map are printed to the same depth. The
+ aim is to give a more consistent output as the order of
+ map keys is not defined. As before, if the depth is less
+ than the number of associations of a map, the selection
+ of associations to print is arbitrary. </p>
+ <p>
+ Own Id: OTP-14983</p>
+ </item>
+ <item>
+ <p> Add functions <c>ordsets:is_empty/1</c> and
+ <c>sets:is_empty/1</c>. </p>
+ <p>
+ Own Id: OTP-14996 Aux Id: ERL-557, PR-1703 </p>
+ </item>
+ <item>
+ <p>
+ Improve performance of <c>string:uppercase/1</c>,
+ <c>string:lowercase/1</c> and <c>string:casefold/1</c>
+ when handling ASCII characters.</p>
+ <p>
+ Own Id: OTP-14998</p>
+ </item>
+ <item>
+ <p>External funs with literal values for module, name,
+ and arity (e.g. <c>erlang:abs/1</c>) are now treated as
+ literals. That means more efficient code that produces
+ less garbage on the heap.</p>
+ <p>
+ Own Id: OTP-15003</p>
+ </item>
+ <item>
+ <p>
+ sys:statistics(Pid,get) did not report 'out' messages
+ from gen_server. This is now corrected.</p>
+ <p>
+ Own Id: OTP-15047</p>
+ </item>
+ <item>
+ <p>
+ A sys debug function can now have the format
+ {Id,Fun,State} in addition to the old {Fun,State}. This
+ allows installing multiple instances of a debug fun.</p>
+ <p>
+ Own Id: OTP-15048</p>
+ </item>
+ <item>
+ <p> The <c>lib</c> module is removed:</p> <list
+ type="bulleted"> <item><c>lib:error_message/2</c> is
+ removed.</item> <item><c>lib:flush_receive/0</c> is
+ removed.</item> <item><c>lib:nonl/1</c> is
+ removed.</item> <item><c>lib:progname/0</c> is replaced
+ by <c>ct:get_progname/0</c>.</item>
+ <item><c>lib:send/2</c> is removed.</item>
+ <item><c>lib:sendw/2</c> is removed.</item> </list>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-15072 Aux Id: PR 1786, OTP-15114 </p>
+ </item>
+ <item>
+ <p>
+ Function <c>ets:delete_all_objects/1</c> now yields the
+ scheduler thread for large tables that take significant
+ time to clear. This to improve real time characteristics
+ of other runnable processes.</p>
+ <p>
+ Own Id: OTP-15078</p>
+ </item>
+ <item>
+ <p> In control sequences of the functions
+ <c>io:fwrite/2,3</c> and <c>io_lib:fwrite/2,3</c>
+ containing <c>p</c> or <c>P</c>, a field width of value
+ <c>0</c> means that no line breaks are inserted. This is
+ in contrast to the old behaviour, where <c>0</c> used to
+ insert line breaks after every subterm. To insert line
+ breaks after every subterm, a field width of value
+ <c>1</c> can be used. </p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-15103 Aux Id: ERL-607 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>STDLIB 3.4.5.1</title>
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>List subtraction (The <c>--</c> operator) will now
+ yield properly on large inputs.</p>
+ <p>
+ Own Id: OTP-15371</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>STDLIB 3.4.5</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ The <c>Module:init/1</c> function in <c>gen_statem</c>
+ may return an actions list containing any action, but an
+ erroneous check only allowed state enter actions so e.g
+ <c>{next_event,internal,event}</c> caused a server crash.
+ This bug has been fixed.</p>
+ <p>
+ Own Id: OTP-13995</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>STDLIB 3.4.4</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p> Correct <c>filelib:find_source()</c> and
+ <c>filelib:find_file()</c> to by default also search one
+ level below <c>src</c>. This is in accordance with the
+ Design Principles which states that an application can
+ have Erlang source files one level below the <c>src</c>
+ directory. </p>
+ <p>
+ Own Id: OTP-14832 Aux Id: ERL-527 </p>
+ </item>
+ <item>
+ <p> The contract of <c>erl_tar:table/2</c> is corrected.
+ </p>
+ <p>
+ Own Id: OTP-14860 Aux Id: PR 1670 </p>
+ </item>
+ <item>
+ <p> Correct a few contracts. </p>
+ <p>
+ Own Id: OTP-14889</p>
+ </item>
+ <item>
+ <p>
+ Fix string:prefix/2 to handle an empty string as second
+ argument.</p>
+ <p>
+ Own Id: OTP-14942 Aux Id: PR-1702 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>STDLIB 3.4.3</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p> Make <c>ets:i/1</c> exit cleaner when ^D is input
+ while browsing a table. Only the old Erlang shell is
+ affected (<c>erl(1)</c> flag <c>-oldshell</c>). </p>
+ <p>
+ Own Id: OTP-14663</p>
+ </item>
+ <item>
+ <p>
+ Fixed handling of windows UNC paths in module
+ <c>filename</c>.</p>
+ <p>
+ Own Id: OTP-14693</p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>
+ Improve performance of the new string functionality when
+ handling ASCII characters.</p>
+ <p>
+ Own Id: OTP-14670</p>
+ </item>
+ <item>
+ <p>
+ Added a clarification to the documentation of
+ <c>unicode:characters_to_list/2</c>.</p>
+ <p>
+ Own Id: OTP-14798</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>STDLIB 3.4.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p> Fix a bug in the Erlang shell where recursively
+ defined records with typed fields could cause a loop.
+ </p>
+ <p>
+ Own Id: OTP-14488 Aux Id: PR-1489 </p>
+ </item>
+ <item>
+ <p>
+ Make edlin handle grapheme clusters instead of codepoints
+ to improve the handling multi-codepoints characters.</p>
+ <p>
+ Own Id: OTP-14542</p>
+ </item>
+ <item>
+ <p>There could be false warnings for
+ <c>erlang:get_stacktrace/0</c> being used outside of a
+ <c>try</c> block when using multiple <c>catch</c>
+ clauses.</p>
+ <p>
+ Own Id: OTP-14600 Aux Id: ERL-478 </p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p> The Erlang code linter no longer checks that the
+ functions mentioned in <c>nowarn_deprecated_function</c>
+ options are declared in the module. </p>
+ <p>
+ Own Id: OTP-14378</p>
+ </item>
+ <item>
+ <p>
+ General Unicode improvements.</p>
+ <p>
+ Own Id: OTP-14462</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>STDLIB 3.4.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p> A bug in <c>proc_lib:format()</c> introduced in
+ Erlang/OTP 20.0 is corrected. </p>
+ <p>
+ Own Id: OTP-14482 Aux Id: PR-1488 </p>
+ </item>
+ <item>
+ <p>
+ Fix string:len/1 to be compatible with previous versions.</p>
+ <p>
+ Own Id: OTP-14487 Aux Id: ERIERL-40 </p>
+ </item>
+ <item>
+ <p>
+ In OTP-20.0, the behavior of c, make, and ct_make was
+ changed so that in some cases the beam files by default
+ would be written to the directory where the source files
+ were found. This is now changed back to the old behavior
+ so beam files are by default written to current
+ directory.</p>
+ <p>
+ Own Id: OTP-14489 Aux Id: ERL-438 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>STDLIB 3.4</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>For many releases, it has been legal to override a BIF
+ with a local function having the same name. However,
+ calling a local function with the same name as guard BIF
+ as filter in a list comprehension was not allowed.</p>
+ <p>
+ Own Id: OTP-13690</p>
+ </item>
+ <item>
+ <p> A new (default) pseudo-random number generator
+ algorithm Xoroshiro116+ has been implemented in the
+ <c>rand</c> module. </p><p> The old algorithm
+ implementations had a number of flaws so they are all
+ deprecated, but corrected versions of two of them have
+ been added. See the documentation. </p>
+ <p>
+ Own Id: OTP-14295 Aux Id: PR-1372 </p>
+ </item>
+ <item>
+ <p> The Erlang shell, <c>qlc:string_to_handle()</c>, and
+ the Debugger (the Evaluator area and Edit variable window
+ of the Bindings area) can parse pids, ports, references,
+ and external funs, as long as they can be created in the
+ running system. </p>
+ <p>
+ Own Id: OTP-14296</p>
+ </item>
+ <item>
+ <p>Internal code change: Calls to <c>catch</c> followed
+ by a call to <c>erlang:get_stacktrace/0</c> has been
+ rewritten to use <c>try</c> instead of <c>catch</c> to
+ make the code future-proof.</p>
+ <p>
+ Own Id: OTP-14400</p>
+ </item>
+ <item>
+ <p> The <c>ms_transform</c> module, used by
+ <c>ets:fun2ms/1</c> and <c>dbg:fun2ms/1</c>, evaluates
+ constant arithmetic expressions. This is necessary since
+ the Erlang compiler, which normally evaluates constant
+ expressions, does not recognize the format generated by
+ <c>ms_transform</c>. </p>
+ <p>
+ Own Id: OTP-14454 Aux Id: ERIERL-29 </p>
+ </item>
+ <item>
+ <p> The state machine engine <c>gen_statem</c> can now
+ handle generic time-outs (multiple named) as well as
+ absolute time-out time. See the documentation. </p><p>
+ The <c>gen_statem</c> callback <c>Module:init/1</c> has
+ become mandatory to harmonize with other <c>gen_*</c>
+ modules. This may be an incompatibility for
+ <c>gen_statem</c> callback modules that use
+ <c>gen_statem:enter_loop/4-6</c>. </p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14531</p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>
+ Improved unicode support for strings. Added normalization
+ functions in the <c>unicode</c> module. Extended the
+ <c>string</c> module API with new functions with improved
+ unicode handling and that works on grapheme clusters. The
+ new functions operates on the <c>unicode:chardata()</c>
+ type, thus they also accept <c>UTF-8 binaries</c> as
+ input. </p>
+ <p>
+ The old string API have been marked as obsolete. The
+ return values have been changed for some error cases.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-10289 Aux Id: OTP-10309 </p>
+ </item>
+ <item>
+ <p>There are two new guard BIFs '<c>floor/1</c>' and
+ '<c>ceil/1</c>'. They both return integers. In the
+ '<c>math</c>' module, there are two new BIFs with the
+ same names that return floating point values.</p>
+ <p>
+ Own Id: OTP-13692</p>
+ </item>
+ <item>
+ <p>
+ Making code_change, terminate and handle_info callbacks
+ optional in the OTP behaviours.</p>
+ <p>
+ Own Id: OTP-13801</p>
+ </item>
+ <item>
+ <p> The support for Dets files created with Erlang/OTP R7
+ and earlier is removed. </p>
+ <p>
+ Own Id: OTP-13830</p>
+ </item>
+ <item>
+ <p>Replaced usage of deprecated symbolic <seealso
+ marker="erts:erlang#type-time_unit"><c>time
+ unit</c></seealso> representations.</p>
+ <p>
+ Own Id: OTP-13831 Aux Id: OTP-13735 </p>
+ </item>
+ <item>
+ <p>The function <c>fmod/2</c> has been added to the
+ <c>math</c> module.</p>
+ <p>
+ Own Id: OTP-14000</p>
+ </item>
+ <item>
+ <p>The EXIT signals received from processes using
+ <c>proc_lib</c> now looks like EXIT signals from
+ processes that were spawned using <c>spawn_link</c>. In
+ particular, that means that the stack trace is now
+ included in the EXIT signal so that it can see where the
+ process crashed.</p>
+ <p>
+ Own Id: OTP-14001</p>
+ </item>
+ <item>
+ <p><c>sets:add_element/2</c> is faster when adding an
+ element that is already present, and
+ <c>sets:del_element/2</c> is faster when the element to
+ be deleted is not present. This optimization can make
+ certain operations, such as sets:union/2 with many
+ overlapping elements, up to two orders of magnitude
+ faster.</p>
+ <p>
+ Own Id: OTP-14035</p>
+ </item>
+ <item>
+ <p>
+ Add information in doc about supervisor shutdown reason
+ when maximum restart frequency is reached.</p>
+ <p>
+ Own Id: OTP-14037 Aux Id: PR-1233 </p>
+ </item>
+ <item>
+ <p>
+ Added <c>rand:jump/[0|1]</c> functions.</p>
+ <p>
+ Own Id: OTP-14038 Aux Id: PR-1235 </p>
+ </item>
+ <item>
+ <p>Functions for detecting changed code has been added.
+ <c>code:modified_modules/0</c> returns all currently
+ loaded modules that have changed on disk.
+ <c>code:module_status/1</c> returns the status for a
+ module. In the shell and in <c>c</c> module, <c>mm/0</c>
+ is short for <c>code:modified_modules/0</c>, and
+ <c>lm/0</c> reloads all currently loaded modules that
+ have changed on disk.</p>
+ <p>
+ Own Id: OTP-14059</p>
+ </item>
+ <item>
+ <p>Each assert macro in <c>assert.hrl</c> now has a
+ corresponding version with an extra argument, for adding
+ comments to assertions. These can for example be printed
+ as part of error reports, to clarify the meaning of the
+ check that failed.</p>
+ <p>
+ Own Id: OTP-14066</p>
+ </item>
+ <item>
+ <p><c>error_logger_tty_h</c> and
+ <c>error_logger_file_h</c> now inserts the node
+ information for nonlocal messages before the message
+ itself instead of after, both for readability and so as
+ not to change the line termination property at the end of
+ the message.</p>
+ <p>
+ Own Id: OTP-14068</p>
+ </item>
+ <item>
+ <p>The Erlang code linter checks for badly formed type
+ constraints. </p>
+ <p>
+ Own Id: OTP-14070 Aux Id: PR-1214 </p>
+ </item>
+ <item>
+ <p>By default, there will now be a warning when
+ <c>export_all</c> is used. The warning can be disabled
+ using <c>nowarn_export_all</c>.</p>
+ <p>
+ Own Id: OTP-14071</p>
+ </item>
+ <item>
+ <p>When a <c>gen_server</c> process crashes, the
+ stacktrace for the client will be printed to facilitate
+ debugging.</p>
+ <p>
+ Own Id: OTP-14089</p>
+ </item>
+ <item>
+ <p>Optimized ETS operations by changing table identifier
+ type from integer to reference. The reference enables a
+ more direct mapping to the table with less potential lock
+ contention and makes especially creation and deletion of
+ tables scale much better.</p> <p>The change of the opaque
+ type for the ETS table identifiers may cause failure in
+ code that make faulty assumptions about this opaque
+ type.</p> <note> <p> The number of tables stored at one
+ Erlang node <em>used</em> to be limited. This is no
+ longer the case (except by memory usage). The previous
+ default limit was about 1400 tables and could be
+ increased by setting the environment variable
+ <c>ERL_MAX_ETS_TABLES</c> before starting the Erlang
+ runtime system. This hard limit has been removed, but it
+ is currently useful to set the <c>ERL_MAX_ETS_TABLES</c>
+ anyway. It should be set to an approximate of the maximum
+ amount of tables used. This since an internal table for
+ named tables is sized using this value. If large amounts
+ of named tables are used and <c>ERL_MAX_ETS_TABLES</c>
+ hasn't been increased, the performance of named table
+ lookup will degrade. </p> </note>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14094</p>
+ </item>
+ <item>
+ <p><c>take/2</c> has been added to <c>dict</c>,
+ <c>orddict</c>, and <c>gb_trees</c>. <c>take_any/2</c>
+ has been added to <c>gb_trees</c>.</p>
+ <p>
+ Own Id: OTP-14102</p>
+ </item>
+ <item>
+ <p>
+ Extend gen_event API to handle options as well.</p>
+ <p>
+ Own Id: OTP-14123</p>
+ </item>
+ <item>
+ <p>
+ Advice on how to tune the supervisor restart frequency
+ (intensity and period) is added to System Documentation -
+ Design Principles - Supervisor Behaviour.</p>
+ <p>
+ Own Id: OTP-14168 Aux Id: PR-1289 </p>
+ </item>
+ <item>
+ <p>
+ gen_fsm is deprecated and is replaced by gen_statem,
+ however for backwards compatibility reasons gen_fsm may
+ continue to exist as an undocumented feature for quite
+ some time.</p>
+ <p>
+ Own Id: OTP-14183</p>
+ </item>
+ <item>
+ <p>The shell functions <c>c/1</c> and <c>c/2</c> have
+ been extended so that if the argument is a module name
+ instead of a file name, it automatically locates the
+ .beam file and the corresponding source file, and then
+ recompiles the module using the same compiler options
+ (plus any options passed to c/2). If compilation fails,
+ the old beam file is preserved. Also adds <c>c(Mod, Opts,
+ Filter)</c>, where the Filter argument allows you to
+ remove old compiler options before the new options are
+ added.</p> <p>New utility functions <c>file_find/2/3</c>
+ and <c>find_source/1/2/3</c> have been added to
+ <c>filelib</c>.</p>
+ <p>
+ Own Id: OTP-14190</p>
+ </item>
+ <item>
+ <p><c>erl_tar</c> in previous versions of OTP only
+ supports the USTAR format. That limited path names to at
+ most 255 bytes, and did not support Unicode characters in
+ names in a portable way.</p>
+ <p><c>erl_tar</c> now has support for reading tar
+ archives in the formats currently in common use, such as
+ v7, STAR, USTAR, PAX, and GNU tar's extensions to the
+ STAR/USTAR format. When writing tar archives,
+ <c>erl_tar</c> can now write them in the <c>PAX</c>
+ format if necessary (for example, to support very long
+ filenames or filenames with Unicode characters). If
+ possible, <c>erl_tar</c> will still write tar archives in
+ the USTAR for maximum portability.</p>
+ <p>
+ Own Id: OTP-14226</p>
+ </item>
+ <item>
+ <p><c>base64:mime_decode/1</c> has been optimized so that
+ it is now almost as fast as<c>base64:decode/1</c>; it
+ used be noticeably slower.</p>
+ <p>
+ Own Id: OTP-14245</p>
+ </item>
+ <item>
+ <p><c>erl_tar</c> will now strip any leading '<c>/</c>'
+ from pathnames when extracting files from a tar archive
+ and write a message to the error logger. There is also
+ new check for directory traversal attacks; if a relative
+ path points above the current working directory the
+ extraction will be aborted.</p>
+ <p>
+ Own Id: OTP-14278</p>
+ </item>
+ <item>
+ <p> Miscellaneous updates due to atoms containing
+ arbitrary Unicode characters. </p>
+ <p>
+ Own Id: OTP-14285</p>
+ </item>
+ <item>
+ <p>
+ The Crypto application now supports generation of
+ cryptographically strong random numbers (floats &lt; 1.0
+ and integer arbitrary ranges) as a plugin to the 'rand'
+ module.</p>
+ <p>
+ Own Id: OTP-14317 Aux Id: PR-1372 </p>
+ </item>
+ <item>
+ <p>
+ Add new function <c>ets:select_replace/2</c> which
+ performs atomic "compare-and-swap" operations for ETS
+ objects using match specifications.</p>
+ <p>
+ Own Id: OTP-14319 Aux Id: PR-1076 </p>
+ </item>
+ <item>
+ <p> The Erlang code linter checks for bad <c>dialyzer</c>
+ attributes. It also checks for bad type variables in type
+ declarations. </p>
+ <p>
+ Own Id: OTP-14323</p>
+ </item>
+ <item>
+ <p> Two new functions has been implemented in the
+ <c>rand</c> module; <c>normal/2</c> and
+ <c>normal_s/3</c>, that both produce normal distribution
+ (pseudo) random numbers with mean value and variance
+ according to arguments. </p>
+ <p>
+ Own Id: OTP-14328 Aux Id: PR-1382 </p>
+ </item>
+ <item>
+ <p>
+ Upgraded the OTP internal PCRE library from version 8.33
+ to version 8.40. This library is used for implementation
+ of the <seealso marker="stdlib:re"><c>re</c></seealso>
+ regular expressions module.</p>
+ <p>
+ Besides various bug fixes, the new version allows for
+ better stack protection. In order to utilize this
+ feature, the stack size of normal scheduler threads is
+ now by default set to 128 kilo words on all platforms.
+ The stack size of normal scheduler threads can be set
+ upon system start by passing the <seealso
+ marker="erts:erl#sched_thread_stack_size"><c>+sss</c></seealso>
+ command line argument to the <seealso
+ marker="erts:erl"><c>erl</c></seealso> command.</p>
+ <p>
+ See <url
+ href="http://pcre.org/original/changelog.txt">http://pcre.org/original/changelog.txt</url>
+ for information about changes made to PCRE between the
+ versions 8.33 and 8.40.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14331 Aux Id: ERL-208 </p>
+ </item>
+ <item>
+ <p>
+ Added function <c>re:version/0</c> which returns
+ information about the OTP internal PCRE version used for
+ implementation of the <c>re</c> module.</p>
+ <p>
+ Own Id: OTP-14347 Aux Id: PR-1412 </p>
+ </item>
+ <item>
+ <p>The format of debug information that is stored in BEAM
+ files (when <c>debug_info</c> is used) has been changed.
+ The purpose of the change is to better support other
+ BEAM-based languages such as Elixir or LFE.</p>
+ <p>All tools included in OTP (dialyzer, debugger, cover,
+ and so on) will handle both the new format and the
+ previous format. Tools that retrieve the debug
+ information using <c>beam_lib:chunk(Beam,
+ [abstract_code])</c> will continue to work with both the
+ new and old format. Tools that call
+ <c>beam_lib:chunk(Beam, ["Abst"])</c> will not work with
+ the new format.</p>
+ <p>For more information, see the description of
+ <c>debug_info</c> in the documentation for
+ <c>beam_lib</c> and the description of the
+ <c>{debug_info,{Backend,Data}}</c> option in the
+ documentation for <c>compile</c>.</p>
+ <p>
+ Own Id: OTP-14369 Aux Id: PR-1367 </p>
+ </item>
+ <item>
+ <p>
+ Add option hibernate_after to gen_server, gen_statem and
+ gen_event. Also added to the deprecated gen_fsm
+ behaviour.</p>
+ <p>
+ Own Id: OTP-14405</p>
+ </item>
+ <item>
+ <p> The size of crash reports created by
+ <c>gen_server</c>, <c>gen_statem</c> and <c>proc_lib</c>
+ is limited with aid of the Kernel application variable
+ <c>error_logger_format_depth</c>. The purpose is to limit
+ the size of the messages sent to the <c>error_logger</c>
+ process when processes with huge message queues or states
+ crash. </p> <p>The crash report generated by
+ <c>proc_lib</c> includes the new tag
+ <c>message_queue_len</c>. The neighbour report also
+ includes the new tag <c>current_stacktrace</c>. Finally,
+ the neighbour report no longer includes the tags
+ <c>messages</c> and <c>dictionary</c>. </p> <p> The new
+ function <c>error_logger:get_format_depth/0</c> can be
+ used to retrieve the value of the Kernel application
+ variable <c>error_logger_format_depth</c>. </p>
+ <p>
+ Own Id: OTP-14417</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
<section><title>STDLIB 3.3</title>
<section><title>Fixed Bugs and Malfunctions</title>
@@ -566,6 +2126,21 @@
</section>
+<section><title>STDLIB 2.8.0.1</title>
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>List subtraction (The <c>--</c> operator) will now
+ yield properly on large inputs.</p>
+ <p>
+ Own Id: OTP-15371</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
<section><title>STDLIB 2.8</title>
<section><title>Fixed Bugs and Malfunctions</title>
@@ -2602,7 +4177,7 @@
you use erlang:halt/2 with an integer first argument and
an option list containing {flush,false} as the second
argument. Note that now is flushing not dependant of the
- exit code, and you can not only flush async threads
+ exit code, and you cannot only flush async threads
operations which we deemed as a strange behaviour anyway.
</p>
<p>Also, erlang:halt/1,2 has gotten a new feature: If the
@@ -3116,9 +4691,9 @@
Supervisors should not save child-specs for temporary
processes when they terminate as they should not be
restarted. Saving the temporary child spec will result in
- that you can not start a new temporary process with the
+ that you cannot start a new temporary process with the
same child spec as an already terminated temporary
- process. Since R14B02 you can not restart a temporary
+ process. Since R14B02 you cannot restart a temporary
temporary process as arguments are no longer saved, it
has however always been semantically incorrect to restart
a temporary process. Thanks to Filipe David Manana for
@@ -3267,7 +4842,7 @@
<p>
Two bugs in io:format for ~F.~Ps has been corrected. When
length(S) >= abs(F) > P, the precision P was incorrectly
- ignored. When F == P > lenght(S) the result was
+ ignored. When F == P > length(S) the result was
incorrectly left adjusted. Bug found by Ali Yakout who
also provided a fix.</p>
<p>
@@ -6735,4 +8310,3 @@
</section>
</section>
</chapter>
-