package lwt

  1. Overview
  2. Docs

CHANGES.html

CHANGES

===== 3.1.0 (2017-07-19) =====

====== Additions ======

  * Port to Jbuilder (#374, Andrew Ray).
  * Lwt_io.establish_server_with_client_address (#346, Rudi Grinberg).
  * Lwt_unix.getcwd (#403, Raphaël Proust).

====== Planned to break in 4.0.0 ======

  * Delete lwt.simple-top (#371).
  * Delete Lwt_chan (#441).

====== Fixes ======

  * Make Lwt_log functions tail-recursive (#348, Jan Doms).
  * Make more of Lwt_list tail-recursive (#347, Jan Doms).
  * Improve string messages in exceptions (#368, #382, Jan Doms, Raphaël
    Proust).
  * Don't call Unix.set_nonblock or Unix.clear_nonblock unnecessarily on
    some fds (#356, David Sheets).
  * Lwt_unix.sleep and Lwt_unix.timeout returning too early when using
    libev (#433, Stijn Devriendt).
  * Lwt_sequence.fold_r iterating the wrong way in some cases (#405,
    Stijn Devriendt).
  * Build conflicts in some cases due to duplicate cst_to_constr
    function (#362, Jérémie Dimino).
  * Don't use deprecated readdir_r system call (#430, Raphaël Proust).

====== Miscellaneous ======

  * The Lwt core, lwt.ml, has been thoroughly refactored and commented
    (#354, reviewed Gabriel Radanne, Edwin Török, Raphaël Proust, Jan
    Doms, Fabian Hemmer, Sebastien Mondet, Simon Cruanes, Anil
    Madhavapeddy, Pierre Chambart, and many others).
  * Lots of tests for most of the Lwt core (#339, #389, #392, #440,
    #448, #450, Joseph Thomas, Ryan Slade).
  * Documentation fixes (including by Joseph Thomas, Raphaël Proust,
    Richard Degenne, Stavros Polymenis).
  * Contributing documentation (#379).
  * Massively adjust whitespace for legibility (#400, #409, #416,
    Richard Degenne).
  * Improvements to CI (Etienne Millon, Raphael Rafatpanah, Zack Coker,
    Yotam Barnoy).
  * The additional packages lwt_ssl, lwt_react, lwt_glib get new minor
    releases, the change being new Jbuilder build systems (#374, Andrew
    Ray).

===== 3.0.0 (2017-04-10) =====

====== Breaking ======

  * These changes were originally announced in release 2.7.0 (#308).
  * Lwt_engine.libev now has an optional argument for selecting the libev back
    end (#269, #294, Jeremy Yallop).
  * Lwt_io.establish_server has been changed to make it more difficult to leak
    file descriptors (#258, #260).
  * Lwt_io.shutdown_server now evaluates to a promise, which completes when the
    listening socket's close(2) operation completes (#259).
  * Lwt_unix.bind now evaluates to a promise, because the bind(2) system call
    can block for Unix domain sockets (#296, requested David Sheets).
  * ocamlfind packages lwt.react, lwt.ssl, lwt.glib are replaced by lwt_react,
    lwt_ssl, lwt_glib. These have been separate OPAM packages, under those
    names, since 2.7.0 (#301).

===== 2.7.1 (2017-04-08) =====

====== Fixes ======

  * OCaml 4.05 compatibility (Mauricio Fernandez, #322).
  * Give Lwt_unix.file_exists the same semantics as Sys.file_exists, with
    respect to not raising Unix.Unix_error (Mauricio Fernandez, #316).
  * Improve diagnostics from build scripts (Tim Cuthbertson, #313, #314).

====== Additions ======

  * Announce Lwt_result, which was originally released as an experimental module
    in release 2.6.0 (Simon Cruanes, #320, #247).

===== 2.7.0 (2017-01-03) =====

====== General ======

  * Values of types a Lwt.t are now referred to as promises rather than threads
    (#300). The manual has not yet been updated.

====== Breaking ======

  * After this release, Lwt will switch to semantic versioning. Future breaking
    changes will first require deprecation, then a major version number increase
    (#293).
  * Lwt no longer supports OCaml 4.01 (#272).
  * Lwt_unix.fdatasync is no longer available on macOS. It was calling an
    undocumented system call on that system (#285, Jeremy Yallop).

====== Planned to break in 3.0.0 ======

  * APIs in this category have deprecation messages attached. The messages will
    be displayed if you recompile your code, and can also be seen in #308.
  * Lwt_engine.libev will have an argument for selecting the libev back end
    (#269, #294, Jeremy Yallop).
  * Lwt_io.establish_server will be replaced by a version that makes it
    difficult to leak file descriptors (#258, #260).
  * Lwt_io.shutdown_server will evaluate to a promise, which indicates when the
    close operation completes (#259).
  * Lwt_unix.bind will evaluate to a promise, since bind can block for Unix
    domain sockets (#296, requested David Sheets).
  * ocamlfind packages lwt.react, lwt.ssl, and lwt.glib will be replaced by the
    new lwt_react, lwt_ssl, and lwt_glib. These are now distributed in new OPAM
    packages with the same names, separately from OPAM package lwt (#301).

====== Additions ======

  * Lwt_unix.readv and Lwt_unix.writev - zero-copy scatter/gather I/O
    (#291, #299).
  * ?fail_on_error argument for Lwt_log.load_rules (#306, Daniil Baturin).
  * Lwt_log.level_of_string (#306, Daniil Baturin).

====== Changes ======

  * Lwt_stream.of_list, Lwt_stream.of_array, Lwt_stream.of_string now
    immediately push all elements into the created streams
    (#239, Spiros Eliopoulos).

====== Deprecations ======

  * Lwt_stream.map_exn in favor of Lwt_stream.wrap_exn, which uses OCaml's
    standard result type (#295).

====== Bugs fixed ======

  * Ungraceful failure if directory handle used after Lwt_unix.closedir (#292).
  * Buffer overflow in Lwt_unix.readdir and Lwt_unix.readdir_n (#292).
  * Unnecessary allocations in Lwt_unix.readdir_n (#292, found Jeremly Yallop).

====== Miscellaneous ======

  * Annotate existing deprecations with [@@ocaml.deprecated ...] (5737f5b).
  * Improvements to the examples (#288, Rich Neswold).
  * Documentation fixes, including by Rich Neswold.
  * New tests and various minor internal improvements.
  * Run tests in CI with all OCaml warnings enabled (dadb926).
  * Much cleaner build output.
  * Add scratch/ directory for local use by developers.

===== 2.6.0 (2016-10-27) =====

====== Additions ======

  * Lwt_stream.closed and Lwt_stream.is_closed (#223, Spiros Eliopoulos).
  * Lwt_switch.with_switch (#256, Thomas Leonard).
  * Define 'a Lwt.result as ('a, exn) result (#247, Simon Cruanes).
  * Lwt_condition.broadcast_exn (#241, Nicolas Ojeda Bar).
  * Lwt_unix.utimes (#193).

====== Bugfixes ======

  * Memory leak in Lwt_unix.readdir_n (#229, diagnosed Thomas Leonard).
  * Memory leak in Lwt.protected (#56, #181, reported @ygrek, Mauricio
    Fernandez).
  * Lwt_switch.turn_off hook exception handling (995b704).
  * Handling of ENOTCONN when channels passed to handler of
    Lwt_io.establish_server are closed (95fb431).
  * Duplicate exceptions on implicit close in Lwt_io.with_connection (b1afe45).
  * Deadlock in Lwt_main.at_exit (#48, #114, reported Jérôme Vouillon, Vincent
    Bernardoff).
  * Performance of Lwt_preemptive.detach (#218, #219, Mauricio Fernandez).
  * Bad hash functions for libev loops (#146, reported Mark Christiaens).
  * Hash of uninitialized data in Lwt_io (#217, reported Jeremy Yallop).
  * Update log sections after Lwt_log.load_rules (#188, reported @rand00).
  * Print three digits for milliseconds in Lwt_log (#264, Fabian Hemmer).
  * Do not truncate Unix job notification ids in C (#277, diagnosed
    @stijn-devriendt).

====== Deprecations ======

  * Lwt_stream.on_termination: bind on Lwt_stream.closed instead.
  * Lwt.make_value, Lwt.make_error: use result's Ok and Error constructors.
  * Lwt_pqueue, Lwt_sequence: use min-heaps and linked lists from another
    library (#135).
  * Pa_lwt, Pa_lwt_log: use Ppx_lwt.

====== Miscellaneous ======

  * Update examples to use PPX syntax instead of Camlp4 (#108, Peter Zotov).
  * Set up Travis, AppVeyor for testing on Linux, OS X, Cygwin, and MinGW. MSVC
    also planned.
  * Large amount of local documentation fixes (Hezekiah Carty, Etienne Millon,
    Leo Wzukw, Sebastien Mondet, reports by others).
  * A bunch of new tests.

===== 2.5.2 (2016-04-25) =====

  * Fix compatibility for 4.03 (#227)
  * Various documentation fixes (#199,#200,#210)
  * Improve wildcard detection in the ppx (#198)
  * Fix Lwt_stream: bounded_push#close wake the reader (#201)
  * Fix infinite loop with Lwt_stream.choose (#214)
  * Fix lazyness failure with Lwt_io.common#close (#207)

===== 2.5.1 (2015-12-07) =====

  * Lwt_stream.on_terminate -> Lwt_stream.on_termination
  * Lwt_unix: handle O_CLOEXEC
  * Lwt_log: add OSX syslog path
  * Ppx: Improve lwt%match, improve catchall detection
  * Add Lwt_unix.file_exists and Lwt_unix.Large_file.file_exists
  * Build fixes

===== 2.5.0 (2015-07-03) =====

  * API CHANGE: Functions in Lwt_io that were previously using a
    ~buffer_size argument now takes a ~buffer argument.
  * Accept ?buffer argument in Lwt_ssl.{in,out}_channel_of_descr.
  * Use newer Ssl bigarray read/write functionality to avoid
    allocation in Lwt_ssl.
  * Fix non-reentrant function calls (#136)
  * IPv4 multicast support.
  * Add support for if%lwt in ppx extension.
  * Add Lwt.return_some.
  * Disable log syntax extension by default in ppx.
    Give [-log] as ppx argument to enable it.
  * Nanosecond precision for Lwt_unix.stat.
  * Minor fixes + documentation improvements.

===== 2.4.8 (2015-03-11) =====

  * Fix compilation under Windows (#117, #129)
  * Fix Lwt_engine.on_timer (#121)
  * Add Lwt_log_core.reset_rules (#123)
  * Fixed typos in the documentation (#119, #131)

===== 2.4.7 (2015-01-06) =====

  * camlp4 is now optional.
  * Add safe_string compliance except for Lwt_ssl (need ocaml-ssl fix).
  * Add Lwt.Infix module to open instead of Lwt to have (>>=), etc.
  * Add Lwt_list.filter_map_{s,p} functions.
  * Add Lwt.fail_{with,invalid_arg} functions.
  * Improved Android support.
  * Remove deprecated lwt.text and lwt.top libraries.
  * Remove deprecated Lwt_signal and Lwt_event modules from
    lwt.react.
  * Fix #111: try_lwt wrongly warns about unused match case.
  * Fix #96: Fix Lwt_react.S.limit and Lwt_react.E.limit.
  * Fix #91: Workaround to fix compilation on OSX.

===== 2.4.6 (2014-10-12) =====

  * Add a ppx syntax extension
  * Add a ?fd argument to
    Lwt_io.{open_connection,with_connection,establish_server}.
  * Fix stub for getaddrinfo and getprotobyname
  * Windows fix: don't throw an exception in the notification handler
    if we're shutting down
  * Fix include file search in ./configure
  * ./configure fixes for windows
  * Fix: use sys_exit instead of exit when Unix.execv fails

===== 2.4.5 (2014-04-21) =====

  * Lwt_ssl: expand API to allow setting socket options with Ssl
    functions
  * fix for camlp4 trunk
  * support for React 1.0.0
  * add Lwt_sequence.find_node_* functions
  * Lwt_log: get backtrace early to overcome exns in
    Printexc.to_string
  * fix potential deadlock in lwt_unix_recv_notifications
  * lwt.glib fixes:
    - handle HUP
    - fix for BSD/OSX
  * do not raise an exception in Lwt_log if argv[0] is blank

===== 2.4.4 (2013-10-22) =====

  * add Android support
  * fix issues in stubs for Lwt_unix jobs
  * fix compatibility issue with OCaml 4.01
  * fix the stub for ev_timer_init
  * add Lwt.log containing Lwt_log_core, the Unix-free part of Lwt_log
  * add Lwt_ssl.get_fd
  * fix stdout/stderr redirections in Lwt_daemon.daemonize
  * add Lwt_list.{map,iter}i{_s,_p}

===== 2.4.3 (2012-12-27) =====

  * fix Lwt_ssl.{in,out}_channel_of_descr: shutdown and close the
    socket when the channel is closed

===== 2.4.2 (2012-09-28) =====

  * fix the stub for Lwt_unix.readdir
  * change the default method for Lwt_glib.install
    (use the glib main loop by default: more portable)
  * ignore invalid file descriptors returned by glib
    (like the emulation of select in glib does)
  * use environment variables in discover.ml
    - use LIBRARY_PATH and C_INCLUDE_PATH for searching headers
    - allow to pass flags for a library in <LIB>_CLFAGS and <LIB>_LIBS
  * add Lwt_unix.on_signal_full

===== 2.4.1 (2012-08-22) =====

  * Add Lwt_stream.on_terminate
  * Fix Lwt_gc
  * Fix stubs for get_credentials on *BSD

===== 2.4.0 (2012-07-16) =====

  * Reimplement Lwt_stream
    - much simpler and more efficient
    - do not use Weak
    - add bounded push streams
  * Add Lwt.async
  * Add Lwt_preemptive.run_in_main
  * Implement Lwt_unix.get_credentials on MacOS X/OpenBSD
  * Ensure that on_cancel functions are executed first
  * Better implementation of Lwt.cancel with more tests
  * Simplify the API for unix jobs
  * Better handling of the master lock in libev stubs
  * Windows fixes/updates:
    - pass -lws2_32 instead of ws2_32.lib if building with mingw
    - fix a bug causing Lwt_unix.read/write to block when a socket
      is not readable/writable
    - port Lwt_process and Lwt_unix.system to Windows
  * Compatibility with OCaml 4.00:
    - add O_SHARE_DELETE to Lwt_unix.open_flag
    - add -package compiler-libs.toplevel for files using Toploop
  * Do not use module Sys for signal handling to avoid
    OCaml code to be called in a C thread
  * Fix Lwt_unix.wrap_syscall: try instead of Lwt.catch
  * Fix a dead-lock between lwt_unix_send_notification
    and lwt_unix_recv_notifications
  * Fix #277: add a function to return the Ssl.socket of a Lwt_ssl.socket
  * Fix problems with C libraries detection/linking

===== 2.3.2 (2011-11-04) =====

  * Add location informations in logs:
    ** allow loggers to get the current location through local storage
    ** pass current location to logging functions
    ** pass the current location with the syntax extension
  * Add Lwt.on_termination
  * Add Lwt_unix.reinstall_signal_handler
  * Add Lwt_io.flush_all
  * Add assert_lwt keyword to the syntax extension
  * Add Lwt.wrap
  * Add Lwt_glib.iter and Lwt_glib.wakeup
  * OCaml 3.13 ready
  * Allow to compile without libev support
  * Fix bugs in Lwt_io
  * Better handling of forks
  * Fix many problems on Windows

===== 2.3.1 (2011-07-13) =====

  * Fix building of documentation when using the tarball
  * Add Lwt_unix.fsync and Lwt_unix.fdatasync
  * Fix the stubs for Lwt_unix.send_msg when fd-passing is not
    available
  * Add -lwt-sequence-strict option to the syntax extension
  * Use a custom PRNG state for Lwt.choose and Lwt.pick
  * Fix a display glitch when starting the toplevel
  * Add Lwt_unix.fork which should now be used when one want to use
    Lwt in the child process
  * Better implementation of Lwt_unix.readlink and
    Lwt_unix.gethostbyname, which fixes compilation on Hurd
  * Add Lwt.wakeup_later and Lwt.wakeup_later_exn to be used when one
    need to do lot of nested wakeup, which fixes a buffer overflow in
    Lwt_mutex
  * Fix Lwt_unix.abort and Lwt_unix.close (threads was never wakeup)
  * Fix Lwt_throttle for correct timings
  * Fix subtle use of cancel

===== 2.3.0 (2011-04-12) =====

  * Add an extensible system of engines to:
    ** allow the user to replace libev by another event system, such
       as select
    ** allow easier integration of external libraries supporting
       asynchronous operations
  * Lots of improvements for Windows:
    ** use the OCaml select instead of libev by default on Windows
    ** make asynchronous operations on non-socket file descriptors
       such as pipes to work
    ** make glib integration to work
  * Better use of engines in Lwt_unix: now events are cached to minimize
    the amount of calls to epoll_ctl
  * Use an eventfd when possible for notifications for faster delivery
  * Add modules:
    ** Lwt_sys: allow to test availability of extra features
    ** Lwt_react: replace Lwt_event and Lwt_signal
  * Allow to configure logging rules at runtime in Lwt_log
  * Add match_lwt and while_lwt to the syntax extension
  * Fixes:
    ** syntax extension: handle "lwt ... = ... in ..." at toplevel
    ** make the notification system fork-proof
    ** fix an issue with stubs not raising correctly exceptions

===== 2.2.1 (2011-01-26) =====

  * Better interaction with Js_of_OCaml.
  * Add functions {{{Lwt.register_pause_notifier}}} and {{{Lwt.paused_count}}}.

===== 2.2.0 (2010-12-13) =====

  * Bugfixes:
    ** Fix a bug with cancellable threads causing {{{Canceled}}}
       exceptions to be raised randomly
    ** Fix a fd-leak in Lwt_io.open_connection
  * {{{Lwt_unix}}} now use libev instead of select
  * Add thread local storage support to {{{Lwt}}}
  * Add backtrace support to {{{Lwt}}}. Now {{{Lwt}}} exceptions can
    be recored by using the syntax extension with the {{{-lwt-debug}}}
    command line switch.
  * Allow blocking system calls to be executed in parallels
  * Change the type of many functions of {{{Lwt_unix}}}, which now
    return a {{{Lwt}}} thread
  * Add functions {{{Lwt_unix.readable}}} and {{{Lwt_unix.writable}}}
  * Add function {{{Lwt_io.is_busy}}}
  * Add functions {{{Lwt_event.delay}}} and {{{Lwt_signal.delay}}}
  * Add function {{{Lwt_term.render_update}}}
  * Add function {{{Lwt_ssl.embed_socket}}}
  * Add module {{{Lwt_bytes}}} defining operations on bigarrays
    instead of strings
  * Use bigarrays in Lwt_io instead of strings for the internal buffer.
    Lwt_io.make now takes a function that uses a bigarray.
  * Add module {{{Lwt_switch}}}

===== 2.1.1 (2010-06-13) =====

  * Many bugfixes, including:
    ** buggy behaviour of cancellable threads
    ** file descriptor leakage in {{{Lwt_unix.accept_n}}}
  * Add {{{Lwt.nchoose}}} and {{{Lwt.npick}}}
  * Use {{{set_close_on_exec}}} for fds created by {{{Lwt_log}}}
  * Better implementation of lwtized react functions

===== 2.1.0 (2010-04-19) =====

  * Rename {{{Lwt.select}}} to {{{Lwt.pick}}}
  * Removing module {{{Lwt_monitor}}} in favour of {{{Lwt_mutex}}} and
    new module {{{Lwt_condition}}}
  * More react helpers:
    ** {{{Lwt_event.next}}}
    ** {{{Lwt_event.limit}}} and {{{Lwt_signal.limit}}}
    ** {{{Lwt_event.from}}}
  * Adding function {{{Lwt_main.fast_yield}}}
  * Adding unit tests
  * Optimisation of {{{Lwt}}}
  * Adding module {{{Lwt_log}}} for logging
  * Adding a camlp4 filter for remmoving logging statement or inlining
    tests
  * Adding module {{{Lwt_daemon}}}
  * Adding function {{{Lwt_unix.recv_msg}}} and {{{Lwt_unix.send_msg}}}
  * Adding function {{{Lwt_unix.wait4}}}
  * Adding function {{{Lwt_io.establish_server}}}
  * Adding module {{{Lwt_list}}}
  * Enhancement in {{{Lwt_process}}}, it now support redirections and
    timeouts
  * Allow to use {{{select}}} on arbitrary high file descriptors
  * More commands and features in {{{Lwt_read_line}}}:
    ** Handle "undo" command
    ** New controlable read-lines instances
    ** More edition commands
    ** Completion as you type
    ** Backward search
  * Enhancement in {{{Lwt_term}}}: more drawing functions and allow to
    put the terminal into drawing mode
  * Optimisation of {{{Lwt_stream}}}
  * Optimisation of {{{Lwt_io.write_char}}} and {{{Lwt_io.read_char}}}
  * Bugfix of {{{Lwt_stream}}}: two parallel {{{Lwt_stream.get}}}
    returned the same value
  * Bugfix in {{{Lwt_unix.connect}}}: it returned immediately on EINPROGRESS
  * Bugfixes in {{{Lwt_glib}}}: file descriptors were not monitored correctly

===== 2.0.0 (2009-10-15) =====

  * Adding modules:
    ** {{{Lwt_stream}}}: lwt-aware version of the {{{Stream}}} module
    ** {{{Lwt_gc}}} for using {{{finalise}}} without
       {{{Lwt_unix.run}}}
    ** {{{Lwt_io}}}: a new implementation of buffered channels with
       more features and better handling of concurrent access
    ** {{{Lwt_text}}}: implementation of text channels
    ** {{{Lwt_process}}}: helpers to spawn processes and communicate
       with them
    ** {{{Lwt_main}}} for abstracting the main loop and allowing
       replacement by a custom main loop
    ** {{{Lwt_glib}}} for integration into the glib main event loop
    ** {{{Lwt_term}}} for interaction with the terminal
    ** {{{Lwt_read_line}}} for interactive user input
    ** {{{Lwt_monitor}}}, {{{Lwt_mvar}}}: combined locks for
       synchronization with conditional variables for notification
    ** {{{Lwt_throttle}}} for limiting rate of execution
       (e.g. for authentication procedure)
    ** {{{Lwt_sequence}}}: mutable sequence of elements
    ** {{{Lwt_event}}}, {{{Lwt_signal}}}: helpers for reactive
       programming with lwt
  * Adding a syntax extension {{{pa_lwt}}}:
    ** handles anonymous bind {{{a >> b}}}
    ** adds syntactic sugar for catching errors (ticket #6)
    ** adds syntactic sugar for parallel let-binding construction
    ** adds syntactic sugar for for-like loops
  * Top-level integration:
    ** threads can runs while reading user input
    ** line editing support
  * New enhanced OCaml toplevel with some basic completion features
  * Adding C stubs to reimplement {{{Unix.read}}} and {{{Unix.write}}}
    with assumption of non-blocking behaviour
  * Adding more functions/helpers in {{{Lwt}}}
  * Fixing memory leaks in {{{Lwt.choose}}}
  * Bugfix in {{{Lwt_chan.close_*}}} (ticket #66)
  * Separate the type of threads (covariant) from the type of thread
    wakeners (contravariant); the type of many functions related to
    {{{Lwt.wait}}} has been changed
  * Add cancelable threads
  * Unix-dependent part is now put in its own archive and findlib
    package.

===== 1.1.0 (2008-06-25) =====

  * Adding module {{{Lwt_pool}}} for creating pools (for example pools
    of connections)
  * Adding a few functions in {{{Lwt_chan}}}
  * Fixing bugs in {{{Lwt_util.map_serial}}} and
    {{{Lwt_util.iter_serial}}}
  * Putting {{{Lwt_preemptive}}}, {{{Lwt_lib}}} and {{{Lwt_ssl}}} in
    separate libraries and findlib subpackages so that lwt.cma depends
    only on unix.cma.

===== 1.0.0 (and before) =====

  * See Ocsigen changelog