cpython/Doc/library/_thread.rst

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:mod:`!_thread` --- Low-level threading API
===========================================
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.. module:: _thread
:synopsis: Low-level threading API.
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.. index::
single: light-weight processes
single: processes, light-weight
single: binary semaphores
single: semaphores, binary
--------------
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This module provides low-level primitives for working with multiple threads
Merged revisions 57778-58052 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r57820 | georg.brandl | 2007-08-31 08:59:27 +0200 (Fri, 31 Aug 2007) | 2 lines Document new shorthand notation for index entries. ........ r57827 | georg.brandl | 2007-08-31 10:47:51 +0200 (Fri, 31 Aug 2007) | 2 lines Fix subitem markup. ........ r57833 | martin.v.loewis | 2007-08-31 12:01:07 +0200 (Fri, 31 Aug 2007) | 1 line Mark registry components as 64-bit on Win64. ........ r57854 | bill.janssen | 2007-08-31 21:02:23 +0200 (Fri, 31 Aug 2007) | 1 line deprecate use of FakeSocket ........ r57855 | bill.janssen | 2007-08-31 21:02:46 +0200 (Fri, 31 Aug 2007) | 1 line remove mentions of socket.ssl in comments ........ r57856 | bill.janssen | 2007-08-31 21:03:31 +0200 (Fri, 31 Aug 2007) | 1 line remove use of non-existent SSLFakeSocket in apparently untested code ........ r57859 | martin.v.loewis | 2007-09-01 08:36:03 +0200 (Sat, 01 Sep 2007) | 3 lines Bug #1737210: Change Manufacturer of Windows installer to PSF. Will backport to 2.5. ........ r57865 | georg.brandl | 2007-09-01 09:51:24 +0200 (Sat, 01 Sep 2007) | 2 lines Fix RST link (backport from Py3k). ........ r57876 | georg.brandl | 2007-09-01 17:49:49 +0200 (Sat, 01 Sep 2007) | 2 lines Document sets' ">" and "<" operations (backport from py3k). ........ r57878 | skip.montanaro | 2007-09-01 19:40:03 +0200 (Sat, 01 Sep 2007) | 4 lines Added a note and examples to explain that re.split does not split on an empty pattern match. (issue 852532). ........ r57879 | walter.doerwald | 2007-09-01 20:18:09 +0200 (Sat, 01 Sep 2007) | 2 lines Fix wrong function names. ........ r57880 | walter.doerwald | 2007-09-01 20:34:05 +0200 (Sat, 01 Sep 2007) | 2 lines Fix typo. ........ r57889 | andrew.kuchling | 2007-09-01 22:31:59 +0200 (Sat, 01 Sep 2007) | 1 line Markup fix ........ r57892 | andrew.kuchling | 2007-09-01 22:43:36 +0200 (Sat, 01 Sep 2007) | 1 line Add various items ........ r57895 | andrew.kuchling | 2007-09-01 23:17:58 +0200 (Sat, 01 Sep 2007) | 1 line Wording change ........ r57896 | andrew.kuchling | 2007-09-01 23:18:31 +0200 (Sat, 01 Sep 2007) | 1 line Add more items ........ r57904 | ronald.oussoren | 2007-09-02 11:46:07 +0200 (Sun, 02 Sep 2007) | 3 lines Macosx: this patch ensures that the value of MACOSX_DEPLOYMENT_TARGET used by the Makefile is also used at configure-time. ........ r57925 | georg.brandl | 2007-09-03 09:16:46 +0200 (Mon, 03 Sep 2007) | 2 lines Fix #883466: don't allow Unicode as arguments to quopri and uu codecs. ........ r57936 | matthias.klose | 2007-09-04 01:33:04 +0200 (Tue, 04 Sep 2007) | 2 lines - Added support for linking the bsddb module against BerkeleyDB 4.6.x. ........ r57954 | mark.summerfield | 2007-09-04 10:16:15 +0200 (Tue, 04 Sep 2007) | 3 lines Added cross-references plus a note about dict & list shallow copying. ........ r57958 | martin.v.loewis | 2007-09-04 11:51:57 +0200 (Tue, 04 Sep 2007) | 3 lines Document that we rely on the OS to release the crypto context. Fixes #1626801. ........ r57960 | martin.v.loewis | 2007-09-04 15:13:14 +0200 (Tue, 04 Sep 2007) | 3 lines Patch #1388440: Add set_completion_display_matches_hook and get_completion_type to readline. ........ r57961 | martin.v.loewis | 2007-09-04 16:19:28 +0200 (Tue, 04 Sep 2007) | 3 lines Patch #1031213: Decode source line in SyntaxErrors back to its original source encoding. Will backport to 2.5. ........ r57972 | matthias.klose | 2007-09-04 20:17:36 +0200 (Tue, 04 Sep 2007) | 3 lines - Makefile.pre.in(buildbottest): Run an optional script pybuildbot.identify to include some information about the build environment. ........ r57973 | matthias.klose | 2007-09-04 21:05:38 +0200 (Tue, 04 Sep 2007) | 2 lines - Makefile.pre.in(buildbottest): Remove whitespace at eol. ........ r57975 | matthias.klose | 2007-09-04 22:46:02 +0200 (Tue, 04 Sep 2007) | 2 lines - Fix libffi configure for hppa*-*-linux* | parisc*-*-linux*. ........ r57980 | bill.janssen | 2007-09-05 02:46:27 +0200 (Wed, 05 Sep 2007) | 1 line SSL certificate distinguished names should be represented by tuples ........ r57985 | martin.v.loewis | 2007-09-05 08:39:17 +0200 (Wed, 05 Sep 2007) | 3 lines Patch #1105: Explain that one needs to build the solution to get dependencies right. ........ r57987 | armin.rigo | 2007-09-05 09:51:21 +0200 (Wed, 05 Sep 2007) | 4 lines PyDict_GetItem() returns a borrowed reference. There are probably a number of places that are open to attacks such as the following one, in bltinmodule.c:min_max(). ........ r57991 | martin.v.loewis | 2007-09-05 13:47:34 +0200 (Wed, 05 Sep 2007) | 3 lines Patch #786737: Allow building in a tree of symlinks pointing to a readonly source. ........ r57993 | georg.brandl | 2007-09-05 15:36:44 +0200 (Wed, 05 Sep 2007) | 2 lines Backport from Py3k: Bug #1684991: explain lookup semantics for __special__ methods (new-style classes only). ........ r58004 | armin.rigo | 2007-09-06 10:30:51 +0200 (Thu, 06 Sep 2007) | 4 lines Patch #1733973 by peaker: ptrace_enter_call() assumes no exception is currently set. This assumption is broken when throwing into a generator. ........ r58006 | armin.rigo | 2007-09-06 11:30:38 +0200 (Thu, 06 Sep 2007) | 4 lines PyDict_GetItem() returns a borrowed reference. This attack is against ceval.c:IMPORT_NAME, which calls an object (__builtin__.__import__) without holding a reference to it. ........ r58013 | georg.brandl | 2007-09-06 16:49:56 +0200 (Thu, 06 Sep 2007) | 2 lines Backport from 3k: #1116: fix reference to old filename. ........ r58021 | thomas.heller | 2007-09-06 22:26:20 +0200 (Thu, 06 Sep 2007) | 1 line Fix typo: c_float represents to C float type. ........ r58022 | skip.montanaro | 2007-09-07 00:29:06 +0200 (Fri, 07 Sep 2007) | 3 lines If this is correct for py3k branch and it's already in the release25-maint branch, seems like it ought to be on the trunk as well. ........ r58023 | gregory.p.smith | 2007-09-07 00:59:59 +0200 (Fri, 07 Sep 2007) | 4 lines Apply the fix from Issue1112 to make this test more robust and keep windows happy. ........ r58031 | brett.cannon | 2007-09-07 05:17:50 +0200 (Fri, 07 Sep 2007) | 4 lines Make uuid1 and uuid4 tests conditional on whether ctypes can be imported; implementation of either function depends on ctypes but uuid as a whole does not. ........ r58032 | brett.cannon | 2007-09-07 06:18:30 +0200 (Fri, 07 Sep 2007) | 6 lines Fix a crasher where Python code managed to infinitely recurse in C code without ever going back out to Python code in PyObject_Call(). Required introducing a static RuntimeError instance so that normalizing an exception there is no reliance on a recursive call that would put the exception system over the recursion check itself. ........ r58034 | thomas.heller | 2007-09-07 08:32:17 +0200 (Fri, 07 Sep 2007) | 1 line Add a 'c_longdouble' type to the ctypes module. ........ r58035 | thomas.heller | 2007-09-07 11:30:40 +0200 (Fri, 07 Sep 2007) | 1 line Remove unneeded #include. ........ r58036 | thomas.heller | 2007-09-07 11:33:24 +0200 (Fri, 07 Sep 2007) | 6 lines Backport from py3k branch: Add a workaround for a strange bug on win64, when _ctypes is compiled with the SDK compiler. This should fix the failing Lib\ctypes\test\test_as_parameter.py test. ........ r58037 | georg.brandl | 2007-09-07 16:14:40 +0200 (Fri, 07 Sep 2007) | 2 lines Fix a wrong indentation for sublists. ........ r58043 | georg.brandl | 2007-09-07 22:10:49 +0200 (Fri, 07 Sep 2007) | 2 lines #1095: ln -f doesn't work portably, fix in Makefile. ........ r58049 | skip.montanaro | 2007-09-08 02:34:17 +0200 (Sat, 08 Sep 2007) | 1 line be explicit about the actual location of the missing file ........
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(also called :dfn:`light-weight processes` or :dfn:`tasks`) --- multiple threads of
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control sharing their global data space. For synchronization, simple locks
Merged revisions 57778-58052 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r57820 | georg.brandl | 2007-08-31 08:59:27 +0200 (Fri, 31 Aug 2007) | 2 lines Document new shorthand notation for index entries. ........ r57827 | georg.brandl | 2007-08-31 10:47:51 +0200 (Fri, 31 Aug 2007) | 2 lines Fix subitem markup. ........ r57833 | martin.v.loewis | 2007-08-31 12:01:07 +0200 (Fri, 31 Aug 2007) | 1 line Mark registry components as 64-bit on Win64. ........ r57854 | bill.janssen | 2007-08-31 21:02:23 +0200 (Fri, 31 Aug 2007) | 1 line deprecate use of FakeSocket ........ r57855 | bill.janssen | 2007-08-31 21:02:46 +0200 (Fri, 31 Aug 2007) | 1 line remove mentions of socket.ssl in comments ........ r57856 | bill.janssen | 2007-08-31 21:03:31 +0200 (Fri, 31 Aug 2007) | 1 line remove use of non-existent SSLFakeSocket in apparently untested code ........ r57859 | martin.v.loewis | 2007-09-01 08:36:03 +0200 (Sat, 01 Sep 2007) | 3 lines Bug #1737210: Change Manufacturer of Windows installer to PSF. Will backport to 2.5. ........ r57865 | georg.brandl | 2007-09-01 09:51:24 +0200 (Sat, 01 Sep 2007) | 2 lines Fix RST link (backport from Py3k). ........ r57876 | georg.brandl | 2007-09-01 17:49:49 +0200 (Sat, 01 Sep 2007) | 2 lines Document sets' ">" and "<" operations (backport from py3k). ........ r57878 | skip.montanaro | 2007-09-01 19:40:03 +0200 (Sat, 01 Sep 2007) | 4 lines Added a note and examples to explain that re.split does not split on an empty pattern match. (issue 852532). ........ r57879 | walter.doerwald | 2007-09-01 20:18:09 +0200 (Sat, 01 Sep 2007) | 2 lines Fix wrong function names. ........ r57880 | walter.doerwald | 2007-09-01 20:34:05 +0200 (Sat, 01 Sep 2007) | 2 lines Fix typo. ........ r57889 | andrew.kuchling | 2007-09-01 22:31:59 +0200 (Sat, 01 Sep 2007) | 1 line Markup fix ........ r57892 | andrew.kuchling | 2007-09-01 22:43:36 +0200 (Sat, 01 Sep 2007) | 1 line Add various items ........ r57895 | andrew.kuchling | 2007-09-01 23:17:58 +0200 (Sat, 01 Sep 2007) | 1 line Wording change ........ r57896 | andrew.kuchling | 2007-09-01 23:18:31 +0200 (Sat, 01 Sep 2007) | 1 line Add more items ........ r57904 | ronald.oussoren | 2007-09-02 11:46:07 +0200 (Sun, 02 Sep 2007) | 3 lines Macosx: this patch ensures that the value of MACOSX_DEPLOYMENT_TARGET used by the Makefile is also used at configure-time. ........ r57925 | georg.brandl | 2007-09-03 09:16:46 +0200 (Mon, 03 Sep 2007) | 2 lines Fix #883466: don't allow Unicode as arguments to quopri and uu codecs. ........ r57936 | matthias.klose | 2007-09-04 01:33:04 +0200 (Tue, 04 Sep 2007) | 2 lines - Added support for linking the bsddb module against BerkeleyDB 4.6.x. ........ r57954 | mark.summerfield | 2007-09-04 10:16:15 +0200 (Tue, 04 Sep 2007) | 3 lines Added cross-references plus a note about dict & list shallow copying. ........ r57958 | martin.v.loewis | 2007-09-04 11:51:57 +0200 (Tue, 04 Sep 2007) | 3 lines Document that we rely on the OS to release the crypto context. Fixes #1626801. ........ r57960 | martin.v.loewis | 2007-09-04 15:13:14 +0200 (Tue, 04 Sep 2007) | 3 lines Patch #1388440: Add set_completion_display_matches_hook and get_completion_type to readline. ........ r57961 | martin.v.loewis | 2007-09-04 16:19:28 +0200 (Tue, 04 Sep 2007) | 3 lines Patch #1031213: Decode source line in SyntaxErrors back to its original source encoding. Will backport to 2.5. ........ r57972 | matthias.klose | 2007-09-04 20:17:36 +0200 (Tue, 04 Sep 2007) | 3 lines - Makefile.pre.in(buildbottest): Run an optional script pybuildbot.identify to include some information about the build environment. ........ r57973 | matthias.klose | 2007-09-04 21:05:38 +0200 (Tue, 04 Sep 2007) | 2 lines - Makefile.pre.in(buildbottest): Remove whitespace at eol. ........ r57975 | matthias.klose | 2007-09-04 22:46:02 +0200 (Tue, 04 Sep 2007) | 2 lines - Fix libffi configure for hppa*-*-linux* | parisc*-*-linux*. ........ r57980 | bill.janssen | 2007-09-05 02:46:27 +0200 (Wed, 05 Sep 2007) | 1 line SSL certificate distinguished names should be represented by tuples ........ r57985 | martin.v.loewis | 2007-09-05 08:39:17 +0200 (Wed, 05 Sep 2007) | 3 lines Patch #1105: Explain that one needs to build the solution to get dependencies right. ........ r57987 | armin.rigo | 2007-09-05 09:51:21 +0200 (Wed, 05 Sep 2007) | 4 lines PyDict_GetItem() returns a borrowed reference. There are probably a number of places that are open to attacks such as the following one, in bltinmodule.c:min_max(). ........ r57991 | martin.v.loewis | 2007-09-05 13:47:34 +0200 (Wed, 05 Sep 2007) | 3 lines Patch #786737: Allow building in a tree of symlinks pointing to a readonly source. ........ r57993 | georg.brandl | 2007-09-05 15:36:44 +0200 (Wed, 05 Sep 2007) | 2 lines Backport from Py3k: Bug #1684991: explain lookup semantics for __special__ methods (new-style classes only). ........ r58004 | armin.rigo | 2007-09-06 10:30:51 +0200 (Thu, 06 Sep 2007) | 4 lines Patch #1733973 by peaker: ptrace_enter_call() assumes no exception is currently set. This assumption is broken when throwing into a generator. ........ r58006 | armin.rigo | 2007-09-06 11:30:38 +0200 (Thu, 06 Sep 2007) | 4 lines PyDict_GetItem() returns a borrowed reference. This attack is against ceval.c:IMPORT_NAME, which calls an object (__builtin__.__import__) without holding a reference to it. ........ r58013 | georg.brandl | 2007-09-06 16:49:56 +0200 (Thu, 06 Sep 2007) | 2 lines Backport from 3k: #1116: fix reference to old filename. ........ r58021 | thomas.heller | 2007-09-06 22:26:20 +0200 (Thu, 06 Sep 2007) | 1 line Fix typo: c_float represents to C float type. ........ r58022 | skip.montanaro | 2007-09-07 00:29:06 +0200 (Fri, 07 Sep 2007) | 3 lines If this is correct for py3k branch and it's already in the release25-maint branch, seems like it ought to be on the trunk as well. ........ r58023 | gregory.p.smith | 2007-09-07 00:59:59 +0200 (Fri, 07 Sep 2007) | 4 lines Apply the fix from Issue1112 to make this test more robust and keep windows happy. ........ r58031 | brett.cannon | 2007-09-07 05:17:50 +0200 (Fri, 07 Sep 2007) | 4 lines Make uuid1 and uuid4 tests conditional on whether ctypes can be imported; implementation of either function depends on ctypes but uuid as a whole does not. ........ r58032 | brett.cannon | 2007-09-07 06:18:30 +0200 (Fri, 07 Sep 2007) | 6 lines Fix a crasher where Python code managed to infinitely recurse in C code without ever going back out to Python code in PyObject_Call(). Required introducing a static RuntimeError instance so that normalizing an exception there is no reliance on a recursive call that would put the exception system over the recursion check itself. ........ r58034 | thomas.heller | 2007-09-07 08:32:17 +0200 (Fri, 07 Sep 2007) | 1 line Add a 'c_longdouble' type to the ctypes module. ........ r58035 | thomas.heller | 2007-09-07 11:30:40 +0200 (Fri, 07 Sep 2007) | 1 line Remove unneeded #include. ........ r58036 | thomas.heller | 2007-09-07 11:33:24 +0200 (Fri, 07 Sep 2007) | 6 lines Backport from py3k branch: Add a workaround for a strange bug on win64, when _ctypes is compiled with the SDK compiler. This should fix the failing Lib\ctypes\test\test_as_parameter.py test. ........ r58037 | georg.brandl | 2007-09-07 16:14:40 +0200 (Fri, 07 Sep 2007) | 2 lines Fix a wrong indentation for sublists. ........ r58043 | georg.brandl | 2007-09-07 22:10:49 +0200 (Fri, 07 Sep 2007) | 2 lines #1095: ln -f doesn't work portably, fix in Makefile. ........ r58049 | skip.montanaro | 2007-09-08 02:34:17 +0200 (Sat, 08 Sep 2007) | 1 line be explicit about the actual location of the missing file ........
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(also called :dfn:`mutexes` or :dfn:`binary semaphores`) are provided.
The :mod:`threading` module provides an easier to use and higher-level
threading API built on top of this module.
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.. index::
single: pthreads
pair: threads; POSIX
.. versionchanged:: 3.7
This module used to be optional, it is now always available.
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This module defines the following constants and functions:
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.. exception:: error
Raised on thread-specific errors.
.. versionchanged:: 3.3
This is now a synonym of the built-in :exc:`RuntimeError`.
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.. data:: LockType
This is the type of lock objects.
.. function:: start_new_thread(function, args[, kwargs])
Start a new thread and return its identifier. The thread executes the
function *function* with the argument list *args* (which must be a tuple).
The optional *kwargs* argument specifies a dictionary of keyword arguments.
When the function returns, the thread silently exits.
When the function terminates with an unhandled exception,
:func:`sys.unraisablehook` is called to handle the exception. The *object*
attribute of the hook argument is *function*. By default, a stack trace is
printed and then the thread exits (but other threads continue to run).
When the function raises a :exc:`SystemExit` exception, it is silently
ignored.
.. audit-event:: _thread.start_new_thread function,args,kwargs start_new_thread
.. versionchanged:: 3.8
:func:`sys.unraisablehook` is now used to handle unhandled exceptions.
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.. function:: interrupt_main(signum=signal.SIGINT, /)
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Simulate the effect of a signal arriving in the main thread.
A thread can use this function to interrupt the main thread, though
there is no guarantee that the interruption will happen immediately.
If given, *signum* is the number of the signal to simulate.
If *signum* is not given, :const:`signal.SIGINT` is simulated.
If the given signal isn't handled by Python (it was set to
:const:`signal.SIG_DFL` or :const:`signal.SIG_IGN`), this function does
nothing.
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.. versionchanged:: 3.10
The *signum* argument is added to customize the signal number.
.. note::
This does not emit the corresponding signal but schedules a call to
the associated handler (if it exists).
If you want to truly emit the signal, use :func:`signal.raise_signal`.
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.. function:: exit()
Raise the :exc:`SystemExit` exception. When not caught, this will cause the
thread to exit silently.
..
function:: exit_prog(status)
Exit all threads and report the value of the integer argument
*status* as the exit status of the entire program.
**Caveat:** code in pending :keyword:`finally` clauses, in this thread
or in other threads, is not executed.
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.. function:: allocate_lock()
Return a new lock object. Methods of locks are described below. The lock is
initially unlocked.
.. function:: get_ident()
Return the 'thread identifier' of the current thread. This is a nonzero
integer. Its value has no direct meaning; it is intended as a magic cookie to
be used e.g. to index a dictionary of thread-specific data. Thread identifiers
may be recycled when a thread exits and another thread is created.
.. function:: get_native_id()
Return the native integral Thread ID of the current thread assigned by the kernel.
This is a non-negative integer.
Its value may be used to uniquely identify this particular thread system-wide
(until the thread terminates, after which the value may be recycled by the OS).
.. availability:: Windows, FreeBSD, Linux, macOS, OpenBSD, NetBSD, AIX, DragonFlyBSD, GNU/kFreeBSD.
.. versionadded:: 3.8
.. versionchanged:: 3.13
Added support for GNU/kFreeBSD.
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.. function:: stack_size([size])
Return the thread stack size used when creating new threads. The optional
*size* argument specifies the stack size to be used for subsequently created
threads, and must be 0 (use platform or configured default) or a positive
integer value of at least 32,768 (32 KiB). If *size* is not specified,
0 is used. If changing the thread stack size is
unsupported, a :exc:`RuntimeError` is raised. If the specified stack size is
invalid, a :exc:`ValueError` is raised and the stack size is unmodified. 32 KiB
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is currently the minimum supported stack size value to guarantee sufficient
stack space for the interpreter itself. Note that some platforms may have
particular restrictions on values for the stack size, such as requiring a
minimum stack size > 32 KiB or requiring allocation in multiples of the system
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memory page size - platform documentation should be referred to for more
information (4 KiB pages are common; using multiples of 4096 for the stack size is
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the suggested approach in the absence of more specific information).
.. availability:: Windows, pthreads.
Unix platforms with POSIX threads support.
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.. data:: TIMEOUT_MAX
The maximum value allowed for the *timeout* parameter of
:meth:`Lock.acquire <threading.Lock.acquire>`. Specifying a timeout greater
than this value will raise an :exc:`OverflowError`.
.. versionadded:: 3.2
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Lock objects have the following methods:
.. method:: lock.acquire(blocking=True, timeout=-1)
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Without any optional argument, this method acquires the lock unconditionally, if
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necessary waiting until it is released by another thread (only one thread at a
time can acquire a lock --- that's their reason for existence).
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If the *blocking* argument is present, the action depends on its
value: if it is false, the lock is only acquired if it can be acquired
immediately without waiting, while if it is true, the lock is acquired
unconditionally as above.
If the floating-point *timeout* argument is present and positive, it
specifies the maximum wait time in seconds before returning. A negative
*timeout* argument specifies an unbounded wait. You cannot specify
a *timeout* if *blocking* is false.
The return value is ``True`` if the lock is acquired successfully,
``False`` if not.
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.. versionchanged:: 3.2
The *timeout* parameter is new.
.. versionchanged:: 3.2
Lock acquires can now be interrupted by signals on POSIX.
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.. method:: lock.release()
Releases the lock. The lock must have been acquired earlier, but not
necessarily by the same thread.
.. method:: lock.locked()
Return the status of the lock: ``True`` if it has been acquired by some thread,
``False`` if not.
In addition to these methods, lock objects can also be used via the
:keyword:`with` statement, e.g.::
import _thread
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a_lock = _thread.allocate_lock()
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with a_lock:
print("a_lock is locked while this executes")
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**Caveats:**
.. index:: pair: module; signal
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* Interrupts always go to the main thread (the :exc:`KeyboardInterrupt`
exception will be received by that thread.)
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* Calling :func:`sys.exit` or raising the :exc:`SystemExit` exception is
Merged revisions 74542,74544-74548,74550,74554-74555,74578,74588,74590,74603,74616-74618,74621 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r74542 | georg.brandl | 2009-08-23 23:28:56 +0200 (So, 23 Aug 2009) | 1 line Restore alphabetic order. ........ r74544 | georg.brandl | 2009-08-24 19:12:30 +0200 (Mo, 24 Aug 2009) | 1 line #6775: fix python.org URLs in README. ........ r74545 | georg.brandl | 2009-08-24 19:14:29 +0200 (Mo, 24 Aug 2009) | 1 line #6772: mention utf-8 as utf8 alias. ........ r74546 | georg.brandl | 2009-08-24 19:20:40 +0200 (Mo, 24 Aug 2009) | 1 line #6725: spell "namespace" consistently. ........ r74547 | georg.brandl | 2009-08-24 19:22:05 +0200 (Mo, 24 Aug 2009) | 1 line #6718: fix example. ........ r74548 | georg.brandl | 2009-08-24 19:24:27 +0200 (Mo, 24 Aug 2009) | 1 line #6677: mention "deleting" as an alias for removing files. ........ r74550 | georg.brandl | 2009-08-24 19:48:40 +0200 (Mo, 24 Aug 2009) | 1 line #6677: note that rmdir only removes empty directories. ........ r74554 | georg.brandl | 2009-08-27 20:59:02 +0200 (Do, 27 Aug 2009) | 1 line Typo fix. ........ r74555 | georg.brandl | 2009-08-27 21:02:43 +0200 (Do, 27 Aug 2009) | 1 line #6787: reference fix. ........ r74578 | tarek.ziade | 2009-08-29 15:33:21 +0200 (Sa, 29 Aug 2009) | 1 line fixed #6801: symmetric_difference_update also accepts pipe ........ r74588 | georg.brandl | 2009-08-30 10:35:01 +0200 (So, 30 Aug 2009) | 1 line #6803: fix old name. ........ r74590 | georg.brandl | 2009-08-30 13:51:53 +0200 (So, 30 Aug 2009) | 1 line #6801: fix copy-paste oversight. ........ r74603 | georg.brandl | 2009-08-31 08:38:29 +0200 (Mo, 31 Aug 2009) | 1 line other -> others where multiple arguments are accepted. ........ r74616 | georg.brandl | 2009-09-01 09:46:26 +0200 (Di, 01 Sep 2009) | 1 line #6808: clarification. ........ r74617 | georg.brandl | 2009-09-01 09:53:37 +0200 (Di, 01 Sep 2009) | 1 line #6765: hint that log(x, base) is not very sophisticated. ........ r74618 | georg.brandl | 2009-09-01 10:00:47 +0200 (Di, 01 Sep 2009) | 1 line #6810: add a link to the section about frame objects instead of just a description where to find it. ........ r74621 | georg.brandl | 2009-09-01 10:06:03 +0200 (Di, 01 Sep 2009) | 1 line #6638: fix wrong parameter name and markup a class. ........
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equivalent to calling :func:`_thread.exit`.
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* It is platform-dependent whether the :meth:`~threading.Lock.acquire` method
on a lock can be interrupted (so that the :exc:`KeyboardInterrupt` exception
will happen immediately, rather than only after the lock has been acquired or
the operation has timed out). It can be interrupted on POSIX, but not on
Windows.
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* When the main thread exits, it is system defined whether the other threads
survive. On most systems, they are killed without executing
:keyword:`try` ... :keyword:`finally` clauses or executing object
destructors.
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