# 초기화, 파이널리제이션 및 스레드

See Python Initialization Configuration for details on how to configure the interpreter prior to initialization.

## 파이썬 초기화 전

파이썬을 내장한 응용 프로그램에서는, 다른 파이썬/C API 함수를 사용하기 전에 `Py_Initialize()` 함수를 호출해야 합니다; 몇 가지 함수와 전역 구성 변수는 예외입니다.

파이썬이 초기화되기 전에 다음 함수를 안전하게 호출할 수 있습니다:

- Functions that initialize the interpreter:

  - `Py_Initialize()`

  - `Py_InitializeEx()`

  - `Py_InitializeFromConfig()`

  - `Py_BytesMain()`

  - `Py_Main()`

  - the runtime pre-initialization functions covered in 파이썬 초기화 구성

- 구성 함수:

  - `PyImport_AppendInittab()`

  - `PyImport_ExtendInittab()`

  - `PyInitFrozenExtensions()`

  - `PyMem_SetAllocator()`

  - `PyMem_SetupDebugHooks()`

  - `PyObject_SetArenaAllocator()`

  - `Py_SetProgramName()`

  - `Py_SetPythonHome()`

  - the configuration functions covered in 파이썬 초기화 구성

- 정보 함수:

  - `Py_IsInitialized()`

  - `PyMem_GetAllocator()`

  - `PyObject_GetArenaAllocator()`

  - `Py_GetBuildInfo()`

  - `Py_GetCompiler()`

  - `Py_GetCopyright()`

  - `Py_GetPlatform()`

  - `Py_GetVersion()`

  - `Py_IsInitialized()`

- 유틸리티:

  - `Py_DecodeLocale()`

  - the status reporting and utility functions covered in 파이썬 초기화 구성

- 메모리 할당자:

  - `PyMem_RawMalloc()`

  - `PyMem_RawRealloc()`

  - `PyMem_RawCalloc()`

  - `PyMem_RawFree()`

- Synchronization:

  - `PyMutex_Lock()`

  - `PyMutex_Unlock()`

참고

Despite their apparent similarity to some of the functions listed above, the following functions should not be called before the interpreter has been initialized: `Py_EncodeLocale()`, `PyEval_InitThreads()`, and `Py_RunMain()`.

## 전역 구성 변수

파이썬에는 다양한 기능과 옵션을 제어하기 위한 전역 구성 변수가 있습니다. 기본적으로, 이러한 플래그는 명령 줄 옵션에 의해 제어됩니다.

옵션에 의해 플래그가 설정되면, 플래그 값은 옵션이 설정된 횟수입니다. 예를 들어, `-b`는 `Py_BytesWarningFlag` 를 1로 설정하고 `-bb`는 `Py_BytesWarningFlag` 를 2로 설정합니다.

int Py_BytesWarningFlag

  This API is kept for backward compatibility: setting `PyConfig.bytes_warning` should be used instead, see Python Initialization Configuration.

  `bytes`나 `bytearray`와 `str`을, 또는 `bytes`를 `int`와 비교할 때 경고를 발행합니다. `2`보다 크거나 같으면 에러를 발행합니다.

  `-b` 옵션으로 설정합니다.

  Deprecated since version 3.12, removed in version 3.15.

int Py_DebugFlag

  This API is kept for backward compatibility: setting `PyConfig.parser_debug` should be used instead, see Python Initialization Configuration.

  구문 분석기 디버깅 출력을 켭니다 (전문가 전용, 컴파일 옵션에 의존합니다).

  `-d` 옵션과 `PYTHONDEBUG` 환경 변수로 설정됩니다.

  Deprecated since version 3.12, removed in version 3.15.

int Py_DontWriteBytecodeFlag

  This API is kept for backward compatibility: setting `PyConfig.write_bytecode` should be used instead, see Python Initialization Configuration.

  0이 아닌 값으로 설정하면, 파이썬은 소스 모듈을 임포트 할 때 `.pyc` 파일을 쓰려고 하지 않습니다.

  `-B` 옵션과 `PYTHONDONTWRITEBYTECODE` 환경 변수로 설정됩니다.

  Deprecated since version 3.12, removed in version 3.15.

int Py_FrozenFlag

  This API is kept for backward compatibility: setting `PyConfig.pathconfig_warnings` should be used instead, see Python Initialization Configuration.

  Private flag used by `_freeze_module` and `frozenmain` programs.

  Deprecated since version 3.12, removed in version 3.15.

int Py_HashRandomizationFlag

  This API is kept for backward compatibility: setting `PyConfig.hash_seed` and `PyConfig.use_hash_seed` should be used instead, see Python Initialization Configuration.

  `PYTHONHASHSEED` 환경 변수가 비어 있지 않은 문자열로 설정되면 `1`로 설정합니다.

  플래그가 0이 아니면, `PYTHONHASHSEED` 환경 변수를 읽어 비밀 해시 시드를 초기화합니다.

  Deprecated since version 3.12, removed in version 3.15.

int Py_IgnoreEnvironmentFlag

  This API is kept for backward compatibility: setting `PyConfig.use_environment` should be used instead, see Python Initialization Configuration.

  Ignore all `PYTHON*` environment variables, e.g. `PYTHONPATH` and `PYTHONHOME`, that might be set.

  `-E`와 `-I` 옵션으로 설정됩니다.

  Deprecated since version 3.12, removed in version 3.15.

int Py_InspectFlag

  This API is kept for backward compatibility: setting `PyConfig.inspect` should be used instead, see Python Initialization Configuration.

  스크립트가 첫 번째 인자로 전달되거나 `-c` 옵션을 사용할 때, `sys.stdin`가 터미널로 보이지 않더라도 스크립트나 명령을 실행한 후 대화 형 모드로 들어갑니다.

  `-i` 옵션과 `PYTHONINSPECT` 환경 변수로 설정됩니다.

  Deprecated since version 3.12, removed in version 3.15.

int Py_InteractiveFlag

  This API is kept for backward compatibility: setting `PyConfig.interactive` should be used instead, see Python Initialization Configuration.

  `-i` 옵션으로 설정됩니다.

  Deprecated since version 3.12, removed in version 3.15.

int Py_IsolatedFlag

  This API is kept for backward compatibility: setting `PyConfig.isolated` should be used instead, see Python Initialization Configuration.

  격리 모드로 파이썬을 실행합니다. 격리 모드에서 `sys.path`는 스크립트의 디렉터리도 사용자의 site-packages 디렉터리도 포함하지 않습니다.

  `-I` 옵션으로 설정됩니다.

  Added in version 3.4.

  Deprecated since version 3.12, removed in version 3.15.

int Py_LegacyWindowsFSEncodingFlag

  This API is kept for backward compatibility: setting `PyPreConfig.legacy_windows_fs_encoding` should be used instead, see Python Initialization Configuration.

  If the flag is non-zero, use the `mbcs` encoding with `replace` error handler, instead of the UTF-8 encoding with `surrogatepass` error handler, for the filesystem encoding and error handler.

  `PYTHONLEGACYWINDOWSFSENCODING` 환경 변수가 비어 있지 않은 문자열로 설정되면 `1`로 설정합니다.

  자세한 내용은 PEP 529를 참조하십시오.

  가용성: Windows.

  Deprecated since version 3.12, removed in version 3.15.

int Py_LegacyWindowsStdioFlag

  This API is kept for backward compatibility: setting `PyConfig.legacy_windows_stdio` should be used instead, see Python Initialization Configuration.

  If the flag is non-zero, use `io.FileIO` instead of `io._WindowsConsoleIO` for `sys` standard streams.

  `PYTHONLEGACYWINDOWSSTDIO` 환경 변수가 비어 있지 않은 문자열로 설정되면 `1`로 설정합니다.

  자세한 내용은 PEP 528을 참조하십시오.

  가용성: Windows.

  Deprecated since version 3.12, removed in version 3.15.

int Py_NoSiteFlag

  This API is kept for backward compatibility: setting `PyConfig.site_import` should be used instead, see Python Initialization Configuration.

  모듈 `site` 임포트와 이에 수반되는 `sys.path`의 사이트 종속적인 조작을 비활성화합니다. 또한 나중에 `site`를 명시적으로 임포트 할 때도 이러한 조작을 비활성화합니다 (트리거 하려면 `site.main()`을 호출하십시오).

  `-S` 옵션으로 설정됩니다.

  Deprecated since version 3.12, removed in version 3.15.

int Py_NoUserSiteDirectory

  This API is kept for backward compatibility: setting `PyConfig.user_site_directory` should be used instead, see Python Initialization Configuration.

  `사용자 site-packages 디렉터리`를 `sys.path`에 추가하지 않습니다.

  `-s`와 `-I` 옵션, 그리고 `PYTHONNOUSERSITE` 환경 변수로 설정됩니다.

  Deprecated since version 3.12, removed in version 3.15.

int Py_OptimizeFlag

  This API is kept for backward compatibility: setting `PyConfig.optimization_level` should be used instead, see Python Initialization Configuration.

  `-O` 옵션과 `PYTHONOPTIMIZE` 환경 변수로 설정됩니다.

  Deprecated since version 3.12, removed in version 3.15.

int Py_QuietFlag

  This API is kept for backward compatibility: setting `PyConfig.quiet` should be used instead, see Python Initialization Configuration.

  대화형 모드에서도 저작권과 버전 메시지를 표시하지 않습니다.

  `-q` 옵션으로 설정됩니다.

  Added in version 3.2.

  Deprecated since version 3.12, removed in version 3.15.

int Py_UnbufferedStdioFlag

  This API is kept for backward compatibility: setting `PyConfig.buffered_stdio` should be used instead, see Python Initialization Configuration.

  stdout과 stderr 스트림을 버퍼링 해제하도록 강제합니다.

  `-u` 옵션과 `PYTHONUNBUFFERED` 환경 변수로 설정됩니다.

  Deprecated since version 3.12, removed in version 3.15.

int Py_VerboseFlag

  This API is kept for backward compatibility: setting `PyConfig.verbose` should be used instead, see Python Initialization Configuration.

  모듈이 초기화될 때마다, 로드된 위치(파일명이나 내장 모듈)를 표시하는 메시지를 인쇄합니다. `2`보다 크거나 같으면, 모듈을 검색할 때 검사되는 각 파일에 대한 메시지를 인쇄합니다. 또한 종료 시 모듈 정리에 대한 정보를 제공합니다.

  `-v` 옵션과 `PYTHONVERBOSE` 환경 변수로 설정됩니다.

  Deprecated since version 3.12, removed in version 3.15.

## 인터프리터 초기화와 파이널리제이션

void Py_Initialize()
  Part of the 안정 ABI.

  파이썬 인터프리터를 초기화합니다. 파이썬을 내장하는 응용 프로그램에서는, 다른 파이썬/C API 함수를 사용하기 전에 호출해야 합니다; 몇 가지 예외는 파이썬 초기화 전을 참조하십시오.

  This initializes the table of loaded modules (`sys.modules`), and creates the fundamental modules `builtins`, `__main__` and `sys`. It also initializes the module search path (`sys.path`). It does not set `sys.argv`; use the Python Initialization Configuration API for that. This is a no-op when called for a second time (without calling `Py_FinalizeEx()` first). There is no return value; it is a fatal error if the initialization fails.

  Use `Py_InitializeFromConfig()` to customize the Python Initialization Configuration.

  참고

  윈도우에서, 콘솔 모드를 `O_TEXT`에서 `O_BINARY`로 변경합니다, C 런타임을 사용하는 콘솔의 비 파이썬 사용에도 영향을 미칩니다.

void Py_InitializeEx(int initsigs)
  Part of the 안정 ABI.

  This function works like `Py_Initialize()` if initsigs is `1`. If initsigs is `0`, it skips initialization registration of signal handlers, which may be useful when CPython is embedded as part of a larger application.

  Use `Py_InitializeFromConfig()` to customize the Python Initialization Configuration.

PyStatus Py_InitializeFromConfig(const PyConfig *config)

  Initialize Python from config configuration, as described in PyConfig를 사용한 초기화.

  See the 파이썬 초기화 구성 section for details on pre-initializing the interpreter, populating the runtime configuration structure, and querying the returned status structure.

int Py_IsInitialized()
  Part of the 안정 ABI.

  파이썬 인터프리터가 초기화되었으면 참(0이 아님)을 반환하고, 그렇지 않으면 거짓(0)을 반환합니다. `Py_FinalizeEx()` 가 호출된 후, `Py_Initialize()`가 다시 호출될 때까지 거짓을 반환합니다.

int Py_IsFinalizing()
  Part of the 안정 ABI 버전 3.13 이후로.

  Return true (non-zero) if the main Python interpreter is shutting down. Return false (zero) otherwise.

  Added in version 3.13.

int Py_FinalizeEx()
  Part of the 안정 ABI 버전 3.6 이후로.

  Undo all initializations made by `Py_Initialize()` and subsequent use of Python/C API functions, and destroy all sub-interpreters (see `Py_NewInterpreter()` below) that were created and not yet destroyed since the last call to `Py_Initialize()`. This is a no-op when called for a second time (without calling `Py_Initialize()` again first).

  Since this is the reverse of `Py_Initialize()`, it should be called in the same thread with the same interpreter active. That means the main thread and the main interpreter. This should never be called while `Py_RunMain()` is running.

  Normally the return value is `0`. If there were errors during finalization (flushing buffered data), `-1` is returned.

  Note that Python will do a best effort at freeing all memory allocated by the Python interpreter. Therefore, any C-Extension should make sure to correctly clean up all of the preveiously allocated PyObjects before using them in subsequent calls to `Py_Initialize()`. Otherwise it could introduce vulnerabilities and incorrect behavior.

  이 함수는 여러 가지 이유로 제공됩니다. 내장 응용 프로그램이 응용 프로그램 자체를 다시 시작하지 않고 파이썬을 다시 시작하고 싶을 수 있습니다. 동적으로 로드할 수 있는 라이브러리(또는 DLL)에서 파이썬 인터프리터를 로드한 응용 프로그램은 DLL을 언로드 하기 전에 파이썬이 할당한 모든 메모리를 해제하고 싶을 수 있습니다. 응용 프로그램에서 메모리 누수를 찾는 동안 개발자는 응용 프로그램을 종료하기 전에 파이썬에서 할당한 모든 메모리를 해제하고 싶을 것입니다.

  Bugs and caveats: The destruction of modules and objects in modules is done in random order; this may cause destructors (`__del__()` methods) to fail when they depend on other objects (even functions) or modules. Dynamically loaded extension modules loaded by Python are not unloaded. Small amounts of memory allocated by the Python interpreter may not be freed (if you find a leak, please report it). Memory tied up in circular references between objects is not freed. Interned strings will all be deallocated regardless of their reference count. Some memory allocated by extension modules may not be freed. Some extensions may not work properly if their initialization routine is called more than once; this can happen if an application calls `Py_Initialize()` and `Py_FinalizeEx()` more than once. `Py_FinalizeEx()` must not be called recursively from within itself. Therefore, it must not be called by any code that may be run as part of the interpreter shutdown process, such as `atexit` handlers, object finalizers, or any code that may be run while flushing the stdout and stderr files.

  인자 없이 감사 이벤트 `cpython._PySys_ClearAuditHooks` 를 발생시킵니다.

  Added in version 3.6.

void Py_Finalize()
  Part of the 안정 ABI.

  이것은 `Py_FinalizeEx()`의 이전 버전과 호환되는 반환 값을 무시하는 버전입니다.

int Py_BytesMain(int argc, char **argv)
  Part of the 안정 ABI 버전 3.8 이후로.

  Similar to `Py_Main()` but argv is an array of bytes strings, allowing the calling application to delegate the text decoding step to the CPython runtime.

  Added in version 3.8.

int Py_Main(int argc, wchar_t **argv)
  Part of the 안정 ABI.

  The main program for the standard interpreter, encapsulating a full initialization/finalization cycle, as well as additional behaviour to implement reading configurations settings from the environment and command line, and then executing `__main__` in accordance with 명령 줄.

  This is made available for programs which wish to support the full CPython command line interface, rather than just embedding a Python runtime in a larger application.

  The argc and argv parameters are similar to those which are passed to a C program’s `main()` function, except that the argv entries are first converted to `wchar_t` using `Py_DecodeLocale()`. It is also important to note that the argument list entries may be modified to point to strings other than those passed in (however, the contents of the strings pointed to by the argument list are not modified).

  The return value is `2` if the argument list does not represent a valid Python command line, and otherwise the same as `Py_RunMain()`.

  In terms of the CPython runtime configuration APIs documented in the runtime configuration section (and without accounting for error handling), `Py_Main` is approximately equivalent to:

      PyConfig config;
      PyConfig_InitPythonConfig(&config);
      PyConfig_SetArgv(&config, argc, argv);
      Py_InitializeFromConfig(&config);
      PyConfig_Clear(&config);

      Py_RunMain();

  In normal usage, an embedding application will call this function instead of calling `Py_Initialize()`, `Py_InitializeEx()` or `Py_InitializeFromConfig()` directly, and all settings will be applied as described elsewhere in this documentation. If this function is instead called after a preceding runtime initialization API call, then exactly which environmental and command line configuration settings will be updated is version dependent (as it depends on which settings correctly support being modified after they have already been set once when the runtime was first initialized).

int Py_RunMain(void)

  Executes the main module in a fully configured CPython runtime.

  Executes the command (`PyConfig.run_command`), the script (`PyConfig.run_filename`) or the module (`PyConfig.run_module`) specified on the command line or in the configuration. If none of these values are set, runs the interactive Python prompt (REPL) using the `__main__` module’s global namespace.

  If `PyConfig.inspect` is not set (the default), the return value will be `0` if the interpreter exits normally (that is, without raising an exception), the exit status of an unhandled `SystemExit`, or `1` for any other unhandled exception.

  If `PyConfig.inspect` is set (such as when the `-i` option is used), rather than returning when the interpreter exits, execution will instead resume in an interactive Python prompt (REPL) using the `__main__` module’s global namespace. If the interpreter exited with an exception, it is immediately raised in the REPL session. The function return value is then determined by the way the REPL session terminates: `0`, `1`, or the status of a `SystemExit`, as specified above.

  This function always finalizes the Python interpreter before it returns.

  See Python Configuration for an example of a customized Python that always runs in isolated mode using `Py_RunMain()`.

int PyUnstable_AtExit(PyInterpreterState *interp, void (*func)(void*), void *data)
  이것은 불안정 API. It may change without warning in minor releases.

  Register an `atexit` callback for the target interpreter interp. This is similar to `Py_AtExit()`, but takes an explicit interpreter and data pointer for the callback.

  There must be an attached thread state for interp.

  Added in version 3.13.

## 프로세스 전체 매개 변수

void Py_SetProgramName(const wchar_t *name)
  Part of the 안정 ABI.

  This API is kept for backward compatibility: setting `PyConfig.program_name` should be used instead, see Python Initialization Configuration.

  This function should be called before `Py_Initialize()` is called for the first time, if it is called at all. It tells the interpreter the value of the `argv[0]` argument to the `main()` function of the program (converted to wide characters). This is used by some other functions below to find the Python run-time libraries relative to the interpreter executable. The default value is `'python'`. The argument should point to a zero-terminated wide character string in static storage whose contents will not change for the duration of the program’s execution. No code in the Python interpreter will change the contents of this storage.

  Use `Py_DecodeLocale()` to decode a bytes string to get a wchar_t* string.

  Deprecated since version 3.11, removed in version 3.15.

const char *Py_GetVersion()
  Part of the 안정 ABI.

  이 파이썬 인터프리터의 버전을 반환합니다. 이것은 다음과 같은 문자열입니다

      "3.0a5+ (py3k:63103M, May 12 2008, 00:53:55) \n[GCC 4.2.3]"

  The first word (up to the first space character) is the current Python version; the first characters are the major and minor version separated by a period. The returned string points into static storage; the caller should not modify its value. The value is available to Python code as `sys.version`.

  See also the `Py_Version` constant.

const char *Py_GetPlatform()
  Part of the 안정 ABI.

  Return the platform identifier for the current platform. On Unix, this is formed from the “official” name of the operating system, converted to lower case, followed by the major revision number; e.g., for Solaris 2.x, which is also known as SunOS 5.x, the value is `'sunos5'`. On macOS, it is `'darwin'`. On Windows, it is `'win'`. The returned string points into static storage; the caller should not modify its value. The value is available to Python code as `sys.platform`.

const char *Py_GetCopyright()
  Part of the 안정 ABI.

  현재 파이썬 버전에 대한 공식 저작권 문자열을 반환합니다, 예를 들어

  `'Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam'`

  반환된 문자열은 정적 저장소를 가리킵니다; 호출자는 값을 수정해서는 안 됩니다. 이 값은 파이썬 코드에서 `sys.copyright`로 사용할 수 있습니다.

const char *Py_GetCompiler()
  Part of the 안정 ABI.

  현재 파이썬 버전을 빌드하는 데 사용된 컴파일러 표시를 대괄호 감싸서 반환합니다, 예를 들면:

      "[GCC 2.7.2.2]"

  반환된 문자열은 정적 저장소를 가리킵니다; 호출자는 값을 수정해서는 안 됩니다. 이 값은 파이썬 코드에서 변수 `sys.version`의 일부로 제공됩니다.

const char *Py_GetBuildInfo()
  Part of the 안정 ABI.

  현재 파이썬 인터프리터 인스턴스의 시퀀스 번호와 빌드 날짜 및 시간에 대한 정보를 반환합니다, 예를 들어

      "#67, Aug  1 1997, 22:34:28"

  반환된 문자열은 정적 저장소를 가리킵니다; 호출자는 값을 수정해서는 안 됩니다. 이 값은 파이썬 코드에서 변수 `sys.version`의 일부로 제공됩니다.

void PySys_SetArgvEx(int argc, wchar_t **argv, int updatepath)
  Part of the 안정 ABI.

  This API is kept for backward compatibility: setting `PyConfig.argv`, `PyConfig.parse_argv` and `PyConfig.safe_path` should be used instead, see Python Initialization Configuration.

  argc 및 argv에 기반해서 `sys.argv`를 설정합니다. 이 매개 변수는 프로그램의 `main()` 함수에 전달된 것과 유사하지만, 첫 번째 항목이 파이썬 인터프리터를 호스팅하는 실행 파일이 아니라 실행될 스크립트 파일을 참조해야 한다는 차이점이 있습니다. 실행할 스크립트가 없으면, argv의 첫 번째 항목은 빈 문자열일 수 있습니다. 이 함수가 `sys.argv` 초기화에 실패하면, `Py_FatalError()`를 사용하여 치명적인 조건을 표시합니다.

  updatepath가 0이면, 여기까지가 이 함수가 하는 모든 일입니다. updatepath가 0이 아니면, 함수는 다음 알고리즘에 따라 `sys.path`도 수정합니다:

  - 기존 스크립트의 이름이 `argv[0]`으로 전달되면, 스크립트가 있는 디렉터리의 절대 경로가 `sys.path` 앞에 추가됩니다.

  - 그렇지 않으면 (즉, argc가 `0`이거나 `argv[0]`이 기존 파일 이름을 가리키지 않으면), `sys.path` 앞에 빈 문자열이 추가됩니다, 이는 현재 작업 디렉터리(`"."`)를 앞에 추가하는 것과 같습니다.

  Use `Py_DecodeLocale()` to decode a bytes string to get a wchar_t* string.

  See also `PyConfig.orig_argv` and `PyConfig.argv` members of the Python Initialization Configuration.

  참고

  It is recommended that applications embedding the Python interpreter for purposes other than executing a single script pass `0` as updatepath, and update `sys.path` themselves if desired. See CVE 2008-5983.

  3.1.3 이전 버전에서는, `PySys_SetArgv()`를 호출한 후 첫 번째 `sys.path` 요소를 수동으로 제거하여 같은 효과를 얻을 수 있습니다, 예를 들어 다음을 사용하여:

      PyRun_SimpleString("import sys; sys.path.pop(0)\n");

  Added in version 3.1.3.

  Deprecated since version 3.11, removed in version 3.15.

void PySys_SetArgv(int argc, wchar_t **argv)
  Part of the 안정 ABI.

  This API is kept for backward compatibility: setting `PyConfig.argv` and `PyConfig.parse_argv` should be used instead, see Python Initialization Configuration.

  이 함수는 python 인터프리터가 `-I`로 시작되지 않는 한 updatepath가 `1`로 설정된 `PySys_SetArgvEx()`처럼 작동합니다.

  Use `Py_DecodeLocale()` to decode a bytes string to get a wchar_t* string.

  See also `PyConfig.orig_argv` and `PyConfig.argv` members of the Python Initialization Configuration.

  버전 3.4에서 변경: updatepath 값은 `-I`에 따라 다릅니다.

  Deprecated since version 3.11, removed in version 3.15.

void Py_SetPythonHome(const wchar_t *home)
  Part of the 안정 ABI.

  This API is kept for backward compatibility: setting `PyConfig.home` should be used instead, see Python Initialization Configuration.

  기본 “홈” 디렉터리, 즉 표준 파이썬 라이브러리의 위치를 설정합니다. 인자 문자열의 의미는 `PYTHONHOME` 을 참조하십시오.

  인자는 프로그램을 실행하는 동안 내용이 변경되지 않는 정적 저장소에 있는 0으로 끝나는 문자열을 가리켜야 합니다. 파이썬 인터프리터의 코드는 이 저장소의 내용을 변경하지 않습니다.

  Use `Py_DecodeLocale()` to decode a bytes string to get a wchar_t* string.

  Deprecated since version 3.11, removed in version 3.15.

## 스레드 상태와 전역 인터프리터 록

Unless on a free-threaded build of CPython, the Python interpreter is not fully thread-safe. In order to support multi-threaded Python programs, there’s a global lock, called the global interpreter lock or GIL, that must be held by the current thread before it can safely access Python objects. Without the lock, even the simplest operations could cause problems in a multi-threaded program: for example, when two threads simultaneously increment the reference count of the same object, the reference count could end up being incremented only once instead of twice.

따라서, GIL을 획득한 스레드만 파이썬 객체에서 작동하거나 파이썬/C API 함수를 호출할 수 있다는 규칙이 있습니다. 동시 실행을 모방하기 위해 인터프리터는 정기적으로 스레드 전환을 시도합니다 (`sys.setswitchinterval()`을 참조하십시오). 록은 파일 읽기나 쓰기와 같은 잠재적인 블로킹 I/O 연산에 대해서도 해제되므로, 그동안 다른 파이썬 스레드가 실행될 수 있습니다.

The Python interpreter keeps some thread-specific bookkeeping information inside a data structure called `PyThreadState`, known as a thread state. Each OS thread has a thread-local pointer to a `PyThreadState`; a thread state referenced by this pointer is considered to be attached.

A thread can only have one attached thread state at a time. An attached thread state is typically analogous with holding the GIL, except on free-threaded builds. On builds with the GIL enabled, attaching a thread state will block until the GIL can be acquired. However, even on builds with the GIL disabled, it is still required to have an attached thread state to call most of the C API.

In general, there will always be an attached thread state when using Python’s C API. Only in some specific cases (such as in a `Py_BEGIN_ALLOW_THREADS` block) will the thread not have an attached thread state. If uncertain, check if `PyThreadState_GetUnchecked()` returns `NULL`.

### Detaching the thread state from extension code

Most extension code manipulating the thread state has the following simple structure:

    Save the thread state in a local variable.
    ... Do some blocking I/O operation ...
    Restore the thread state from the local variable.

이것은 매우 일반적이어서 이를 단순화하기 위해 한 쌍의 매크로가 존재합니다:

    Py_BEGIN_ALLOW_THREADS
    ... Do some blocking I/O operation ...
    Py_END_ALLOW_THREADS

`Py_BEGIN_ALLOW_THREADS` 매크로는 새 블록을 열고 숨겨진 지역 변수를 선언합니다; `Py_END_ALLOW_THREADS` 매크로는 블록을 닫습니다.

위의 블록은 다음 코드로 확장됩니다:

    PyThreadState *_save;

    _save = PyEval_SaveThread();
    ... Do some blocking I/O operation ...
    PyEval_RestoreThread(_save);

Here is how these functions work:

The attached thread state holds the GIL for the entire interpreter. When detaching the attached thread state, the GIL is released, allowing other threads to attach a thread state to their own thread, thus getting the GIL and can start executing. The pointer to the prior attached thread state is stored as a local variable. Upon reaching `Py_END_ALLOW_THREADS`, the thread state that was previously attached is passed to `PyEval_RestoreThread()`. This function will block until another releases its thread state, thus allowing the old thread state to get re-attached and the C API can be called again.

For free-threaded builds, the GIL is normally out of the question, but detaching the thread state is still required for blocking I/O and long operations. The difference is that threads don’t have to wait for the GIL to be released to attach their thread state, allowing true multi-core parallelism.

참고

Calling system I/O functions is the most common use case for detaching the thread state, but it can also be useful before calling long-running computations which don’t need access to Python objects, such as compression or cryptographic functions operating over memory buffers. For example, the standard `zlib` and `hashlib` modules detach the thread state when compressing or hashing data.

### 파이썬이 만들지 않은 스레드

When threads are created using the dedicated Python APIs (such as the `threading` module), a thread state is automatically associated to them and the code showed above is therefore correct. However, when threads are created from C (for example by a third-party library with its own thread management), they don’t hold the GIL, because they don’t have an attached thread state.

If you need to call Python code from these threads (often this will be part of a callback API provided by the aforementioned third-party library), you must first register these threads with the interpreter by creating an attached thread state before you can start using the Python/C API. When you are done, you should detach the thread state, and finally free it.

`PyGILState_Ensure()`와 `PyGILState_Release()` 함수는 위의 모든 작업을 자동으로 수행합니다. C 스레드에서 파이썬을 호출하는 일반적인 관용구는 다음과 같습니다:

    PyGILState_STATE gstate;
    gstate = PyGILState_Ensure();

    /* Perform Python actions here. */
    result = CallSomeFunction();
    /* evaluate result or handle exception */

    /* Release the thread. No Python API allowed beyond this point. */
    PyGILState_Release(gstate);

Note that the `PyGILState_*` functions assume there is only one global interpreter (created automatically by `Py_Initialize()`). Python supports the creation of additional interpreters (using `Py_NewInterpreter()`), but mixing multiple interpreters and the `PyGILState_*` API is unsupported. This is because `PyGILState_Ensure()` and similar functions default to attaching a thread state for the main interpreter, meaning that the thread can’t safely interact with the calling subinterpreter.

### Supporting subinterpreters in non-Python threads

If you would like to support subinterpreters with non-Python created threads, you must use the `PyThreadState_*` API instead of the traditional `PyGILState_*` API.

In particular, you must store the interpreter state from the calling function and pass it to `PyThreadState_New()`, which will ensure that the thread state is targeting the correct interpreter:

    /* The return value of PyInterpreterState_Get() from the
       function that created this thread. */
    PyInterpreterState *interp = ThreadData->interp;
    PyThreadState *tstate = PyThreadState_New(interp);
    PyThreadState_Swap(tstate);

    /* GIL of the subinterpreter is now held.
       Perform Python actions here. */
    result = CallSomeFunction();
    /* evaluate result or handle exception */

    /* Destroy the thread state. No Python API allowed beyond this point. */
    PyThreadState_Clear(tstate);
    PyThreadState_DeleteCurrent();

### fork()에 대한 주의 사항

스레드에 대해 주목해야 할 또 다른 중요한 점은 C `fork()` 호출 시 스레드의 동작입니다. `fork()`를 사용하는 대부분의 시스템에서는, 프로세스가 포크한 후에 포크를 발행한 스레드만 존재합니다. 이는 록을 처리해야 하는 방법과 CPython 런타임에 저장된 모든 상태 모두에 구체적인 영향을 미칩니다.

The fact that only the “current” thread remains means any locks held by other threads will never be released. Python solves this for `os.fork()` by acquiring the locks it uses internally before the fork, and releasing them afterwards. In addition, it resets any Lock objects in the child. When extending or embedding Python, there is no way to inform Python of additional (non-Python) locks that need to be acquired before or reset after a fork. OS facilities such as `pthread_atfork()` would need to be used to accomplish the same thing. Additionally, when extending or embedding Python, calling `fork()` directly rather than through `os.fork()` (and returning to or calling into Python) may result in a deadlock by one of Python’s internal locks being held by a thread that is defunct after the fork. `PyOS_AfterFork_Child()` tries to reset the necessary locks, but is not always able to.

다른 모든 스레드가 사라진다는 사실은 또한 CPython의 런타임 상태가 `os.fork()`와 마찬가지로 적절하게 정리되어야 함을 의미합니다. 이것은 현재 인터프리터와 다른 모든 `PyInterpreterState` 객체에 속하는 다른 모든 `PyThreadState` 객체를 파이널리제이션 하는 것을 의미합니다. 이것과 “메인” 인터프리터의 특수한 특성으로 인해, `fork()`는 CPython 전역 런타임이 원래 초기화된 인터프리터의 “메인” 스레드에서만 호출되어야 합니다. 유일한 예외는 `exec()`가 그 후에 즉시 호출되는 경우입니다.

### Cautions regarding runtime finalization

In the late stage of interpreter shutdown, after attempting to wait for non-daemon threads to exit (though this can be interrupted by `KeyboardInterrupt`) and running the `atexit` functions, the runtime is marked as finalizing: `Py_IsFinalizing()` and `sys.is_finalizing()` return true. At this point, only the finalization thread that initiated finalization (typically the main thread) is allowed to acquire the GIL.

If any thread, other than the finalization thread, attempts to attach a thread state during finalization, either explicitly or implicitly, the thread enters a permanently blocked state where it remains until the program exits. In most cases this is harmless, but this can result in deadlock if a later stage of finalization attempts to acquire a lock owned by the blocked thread, or otherwise waits on the blocked thread.

Gross? Yes. This prevents random crashes and/or unexpectedly skipped C++ finalizations further up the call stack when such threads were forcibly exited here in CPython 3.13 and earlier. The CPython runtime thread state C APIs have never had any error reporting or handling expectations at thread state attachment time that would’ve allowed for graceful exit from this situation. Changing that would require new stable C APIs and rewriting the majority of C code in the CPython ecosystem to use those with error handling.

### 고수준 API

다음은 C 확장 코드를 작성하거나 파이썬 인터프리터를 내장할 때 가장 일반적으로 사용되는 형과 함수입니다:

type PyInterpreterState
  Part of the 제한된 API (as an opaque struct).

  이 자료 구조는 여러 협력 스레드가 공유하는 상태를 나타냅니다. 같은 인터프리터에 속하는 스레드는 모듈 관리와 몇 가지 다른 내부 항목을 공유합니다. 이 구조체에는 공개 멤버가 없습니다.

  다른 인터프리터에 속한 스레드는 사용 가능한 메모리, 열린 파일 기술자 등과 같은 프로세스 상태를 제외하고는, 처음에는 아무것도 공유하지 않습니다. 전역 인터프리터 록은 어떤 인터프리터에 속해 있는지에 관계없이 모든 스레드에서 공유됩니다.

  버전 3.12에서 변경: PEP 684 introduced the possibility of a per-interpreter GIL. See `Py_NewInterpreterFromConfig()`.

type PyThreadState
  Part of the 제한된 API (as an opaque struct).

  This data structure represents the state of a single thread. The only public data member is:

  PyInterpreterState *interp

    This thread’s interpreter state.

void PyEval_InitThreads()
  Part of the 안정 ABI.

  아무것도 하지 않는 폐지된 함수.

  파이썬 3.6과 이전 버전에서는, 이 함수가 존재하지 않으면 GIL을 만들었습니다.

  버전 3.9에서 변경: 이제 이 함수는 아무 작업도 수행하지 않습니다.

  버전 3.7에서 변경: 이 함수는 이제 `Py_Initialize()`에 의해 호출되어서, 여러분은 더는 직접 호출할 필요가 없습니다.

  버전 3.2에서 변경: 이 함수는 더는 `Py_Initialize()` 전에 호출할 수 없습니다.

  버전 3.9부터 폐지됨.

PyThreadState *PyEval_SaveThread()
  Part of the 안정 ABI.

  Detach the attached thread state and return it. The thread will have no thread state upon returning.

void PyEval_RestoreThread(PyThreadState *tstate)
  Part of the 안정 ABI.

  Set the attached thread state to tstate. The passed thread state should not be attached, otherwise deadlock ensues. tstate will be attached upon returning.

  참고

  Calling this function from a thread when the runtime is finalizing will hang the thread until the program exits, even if the thread was not created by Python. Refer to Cautions regarding runtime finalization for more details.

  버전 3.14에서 변경: Hangs the current thread, rather than terminating it, if called while the interpreter is finalizing.

PyThreadState *PyThreadState_Get()
  Part of the 안정 ABI.

  Return the attached thread state. If the thread has no attached thread state, (such as when inside of `Py_BEGIN_ALLOW_THREADS` block), then this issues a fatal error (so that the caller needn’t check for `NULL`).

  See also `PyThreadState_GetUnchecked()`.

PyThreadState *PyThreadState_GetUnchecked()

  Similar to `PyThreadState_Get()`, but don’t kill the process with a fatal error if it is NULL. The caller is responsible to check if the result is NULL.

  Added in version 3.13: In Python 3.5 to 3.12, the function was private and known as `_PyThreadState_UncheckedGet()`.

PyThreadState *PyThreadState_Swap(PyThreadState *tstate)
  Part of the 안정 ABI.

  Set the attached thread state to tstate, and return the thread state that was attached prior to calling.

  This function is safe to call without an attached thread state; it will simply return `NULL` indicating that there was no prior thread state.

  더 보기

  `PyEval_ReleaseThread()`

  참고

  Similar to `PyGILState_Ensure()`, this function will hang the thread if the runtime is finalizing.

다음 함수는 스레드 로컬 저장소를 사용하며, 서브 인터프리터와 호환되지 않습니다:

type PyGILState_STATE
  Part of the 안정 ABI.

  The type of the value returned by `PyGILState_Ensure()` and passed to `PyGILState_Release()`.

  enumerator PyGILState_LOCKED

    The GIL was already held when `PyGILState_Ensure()` was called.

  enumerator PyGILState_UNLOCKED

    The GIL was not held when `PyGILState_Ensure()` was called.

PyGILState_STATE PyGILState_Ensure()
  Part of the 안정 ABI.

  Ensure that the current thread is ready to call the Python C API regardless of the current state of Python, or of the attached thread state. This may be called as many times as desired by a thread as long as each call is matched with a call to `PyGILState_Release()`. In general, other thread-related APIs may be used between `PyGILState_Ensure()` and `PyGILState_Release()` calls as long as the thread state is restored to its previous state before the Release(). For example, normal usage of the `Py_BEGIN_ALLOW_THREADS` and `Py_END_ALLOW_THREADS` macros is acceptable.

  The return value is an opaque “handle” to the attached thread state when `PyGILState_Ensure()` was called, and must be passed to `PyGILState_Release()` to ensure Python is left in the same state. Even though recursive calls are allowed, these handles cannot be shared - each unique call to `PyGILState_Ensure()` must save the handle for its call to `PyGILState_Release()`.

  When the function returns, there will be an attached thread state and the thread will be able to call arbitrary Python code. Failure is a fatal error.

  경고

  Calling this function when the runtime is finalizing is unsafe. Doing so will either hang the thread until the program ends, or fully crash the interpreter in rare cases. Refer to Cautions regarding runtime finalization for more details.

  버전 3.14에서 변경: Hangs the current thread, rather than terminating it, if called while the interpreter is finalizing.

void PyGILState_Release(PyGILState_STATE)
  Part of the 안정 ABI.

  이전에 획득 한 모든 자원을 해제합니다. 이 호출 후에, 파이썬의 상태는 해당 `PyGILState_Ensure()` 호출 이전과 같습니다 (그러나 일반적으로 이 상태는 호출자에게 알려지지 않아서, GILState API를 사용합니다).

  `PyGILState_Ensure()`에 대한 모든 호출은 같은 스레드에서 `PyGILState_Release()`에 대한 호출과 쌍을 이뤄야 합니다.

PyThreadState *PyGILState_GetThisThreadState()
  Part of the 안정 ABI.

  Get the attached thread state for this thread. May return `NULL` if no GILState API has been used on the current thread. Note that the main thread always has such a thread-state, even if no auto-thread-state call has been made on the main thread. This is mainly a helper/diagnostic function.

  참고

  This function may return non-`NULL` even when the thread state is detached. Prefer `PyThreadState_Get()` or `PyThreadState_GetUnchecked()` for most cases.

  더 보기

  `PyThreadState_Get()`

int PyGILState_Check()

  Return `1` if the current thread is holding the GIL and `0` otherwise. This function can be called from any thread at any time. Only if it has had its thread state initialized via `PyGILState_Ensure()` will it return `1`. This is mainly a helper/diagnostic function. It can be useful for example in callback contexts or memory allocation functions when knowing that the GIL is locked can allow the caller to perform sensitive actions or otherwise behave differently.

  참고

  If the current Python process has ever created a subinterpreter, this function will always return `1`. Prefer `PyThreadState_GetUnchecked()` for most cases.

  Added in version 3.4.

다음 매크로는 일반적으로 후행 세미콜론 없이 사용됩니다; 파이썬 소스 배포에서 사용 예를 찾으십시오.

Py_BEGIN_ALLOW_THREADS
  Part of the 안정 ABI.

  이 매크로는 `{ PyThreadState *_save; _save = PyEval_SaveThread();` 로 확장됩니다. 여는 중괄호가 포함되어 있음에 유의하십시오; 뒤따르는 `Py_END_ALLOW_THREADS` 매크로와 일치해야 합니다. 이 매크로에 대한 자세한 내용은 위를 참조하십시오.

Py_END_ALLOW_THREADS
  Part of the 안정 ABI.

  이 매크로는 `PyEval_RestoreThread(_save); }`로 확장됩니다. 닫는 중괄호가 포함되어 있음에 유의하십시오; 이전 `Py_BEGIN_ALLOW_THREADS` 매크로와 일치해야 합니다. 이 매크로에 대한 자세한 내용은 위를 참조하십시오.

Py_BLOCK_THREADS
  Part of the 안정 ABI.

  이 매크로는 `PyEval_RestoreThread(_save);` 로 확장됩니다: 닫는 중괄호가 없는 `Py_END_ALLOW_THREADS`와 동등합니다.

Py_UNBLOCK_THREADS
  Part of the 안정 ABI.

  이 매크로는 `_save = PyEval_SaveThread();` 로 확장됩니다: 여는 중괄호와 변수 선언이 없는 `Py_BEGIN_ALLOW_THREADS`와 동등합니다.

### 저수준 API

다음 함수는 모두 `Py_Initialize()` 이후에 호출되어야 합니다.

버전 3.7에서 변경: `Py_Initialize()` now initializes the GIL and sets an attached thread state.

PyInterpreterState *PyInterpreterState_New()
  Part of the 안정 ABI.

  Create a new interpreter state object. An attached thread state is not needed, but may optionally exist if it is necessary to serialize calls to this function.

  인자 없이 감사 이벤트 `cpython.PyInterpreterState_New`를 발생시킵니다.

void PyInterpreterState_Clear(PyInterpreterState *interp)
  Part of the 안정 ABI.

  Reset all information in an interpreter state object. There must be an attached thread state for the interpreter.

  인자 없이 감사 이벤트 `cpython.PyInterpreterState_Clear`를 발생시킵니다.

void PyInterpreterState_Delete(PyInterpreterState *interp)
  Part of the 안정 ABI.

  Destroy an interpreter state object. There should not be an attached thread state for the target interpreter. The interpreter state must have been reset with a previous call to `PyInterpreterState_Clear()`.

PyThreadState *PyThreadState_New(PyInterpreterState *interp)
  Part of the 안정 ABI.

  Create a new thread state object belonging to the given interpreter object. An attached thread state is not needed.

void PyThreadState_Clear(PyThreadState *tstate)
  Part of the 안정 ABI.

  Reset all information in a thread state object. tstate must be attached

  버전 3.9에서 변경: This function now calls the `PyThreadState.on_delete` callback. Previously, that happened in `PyThreadState_Delete()`.

  버전 3.13에서 변경: The `PyThreadState.on_delete` callback was removed.

void PyThreadState_Delete(PyThreadState *tstate)
  Part of the 안정 ABI.

  Destroy a thread state object. tstate should not be attached to any thread. tstate must have been reset with a previous call to `PyThreadState_Clear()`.

void PyThreadState_DeleteCurrent(void)

  Detach the attached thread state (which must have been reset with a previous call to `PyThreadState_Clear()`) and then destroy it.

  No thread state will be attached upon returning.

PyFrameObject *PyThreadState_GetFrame(PyThreadState *tstate)
  Part of the 안정 ABI 버전 3.10 이후로.

  파이썬 스레드 상태 tstate의 현재 프레임을 가져옵니다.

  Return a strong reference. Return `NULL` if no frame is currently executing.

  `PyEval_GetFrame()`도 참조하십시오.

  tstate must not be `NULL`, and must be attached.

  Added in version 3.9.

uint64_t PyThreadState_GetID(PyThreadState *tstate)
  Part of the 안정 ABI 버전 3.10 이후로.

  Get the unique thread state identifier of the Python thread state tstate.

  tstate must not be `NULL`, and must be attached.

  Added in version 3.9.

PyInterpreterState *PyThreadState_GetInterpreter(PyThreadState *tstate)
  Part of the 안정 ABI 버전 3.10 이후로.

  파이썬 스레드 상태 tstate의 인터프리터를 가져옵니다.

  tstate must not be `NULL`, and must be attached.

  Added in version 3.9.

void PyThreadState_EnterTracing(PyThreadState *tstate)

  Suspend tracing and profiling in the Python thread state tstate.

  Resume them using the `PyThreadState_LeaveTracing()` function.

  Added in version 3.11.

void PyThreadState_LeaveTracing(PyThreadState *tstate)

  Resume tracing and profiling in the Python thread state tstate suspended by the `PyThreadState_EnterTracing()` function.

  See also `PyEval_SetTrace()` and `PyEval_SetProfile()` functions.

  Added in version 3.11.

int PyUnstable_ThreadState_SetStackProtection(PyThreadState *tstate, void *stack_start_addr, size_t stack_size)
  이것은 불안정 API. It may change without warning in minor releases.

  Set the stack protection start address and stack protection size of a Python thread state.

  On success, return `0`. On failure, set an exception and return `-1`.

  CPython implements recursion control for C code by raising `RecursionError` when it notices that the machine execution stack is close to overflow. See for example the `Py_EnterRecursiveCall()` function. For this, it needs to know the location of the current thread’s stack, which it normally gets from the operating system. When the stack is changed, for example using context switching techniques like the Boost library’s `boost::context`, you must call `PyUnstable_ThreadState_SetStackProtection()` to inform CPython of the change.

  Call `PyUnstable_ThreadState_SetStackProtection()` either before or after changing the stack. Do not call any other Python C API between the call and the stack change.

  See `PyUnstable_ThreadState_ResetStackProtection()` for undoing this operation.

  Added in version 3.15.

void PyUnstable_ThreadState_ResetStackProtection(PyThreadState *tstate)
  이것은 불안정 API. It may change without warning in minor releases.

  Reset the stack protection start address and stack protection size of a Python thread state to the operating system defaults.

  See `PyUnstable_ThreadState_SetStackProtection()` for an explanation.

  Added in version 3.15.

PyInterpreterState *PyInterpreterState_Get(void)
  Part of the 안정 ABI 버전 3.9 이후로.

  현재 인터프리터를 가져옵니다.

  Issue a fatal error if there no attached thread state. It cannot return NULL.

  Added in version 3.9.

int64_t PyInterpreterState_GetID(PyInterpreterState *interp)
  Part of the 안정 ABI 버전 3.7 이후로.

  인터프리터의 고유 ID를 반환합니다. 그렇게 하는데 에러가 발생하면 `-1`이 반환되고 에러가 설정됩니다.

  The caller must have an attached thread state.

  Added in version 3.7.

PyObject *PyInterpreterState_GetDict(PyInterpreterState *interp)
  반환값: 빌린 참조. Part of the 안정 ABI 버전 3.8 이후로.

  인터프리터별 데이터가 저장될 수 있는 딕셔너리를 반환합니다. 이 함수가 `NULL`을 반환하면 예외는 발생하지 않았고 호출자는 인터프리터별 딕셔너리를 사용할 수 없다고 가정해야 합니다.

  이것은 확장이 인터프리터별 상태 정보를 저장하는 데 사용해야 하는 `PyModule_GetState()`를 대체하는 것이 아닙니다.

  The returned dictionary is borrowed from the interpreter and is valid until interpreter shutdown.

  Added in version 3.8.

typedef PyObject *(*_PyFrameEvalFunction)(PyThreadState *tstate, _PyInterpreterFrame *frame, int throwflag)

  프레임 평가 함수의 형.

  throwflag 매개 변수는 제너레이터의 `throw()` 메서드에서 사용됩니다: 0이 아니면, 현재 예외를 처리합니다.

  버전 3.9에서 변경: 이제 함수는 tstate 매개 변수를 취합니다.

  버전 3.11에서 변경: The frame parameter changed from `PyFrameObject*` to `_PyInterpreterFrame*`.

_PyFrameEvalFunction _PyInterpreterState_GetEvalFrameFunc(PyInterpreterState *interp)

  프레임 평가 함수를 가져옵니다.

  PEP 523 “CPython에 프레임 평가 API 추가”를 참조하십시오.

  Added in version 3.9.

void _PyInterpreterState_SetEvalFrameFunc(PyInterpreterState *interp, _PyFrameEvalFunction eval_frame)

  프레임 평가 함수를 설정합니다.

  PEP 523 “CPython에 프레임 평가 API 추가”를 참조하십시오.

  Added in version 3.9.

PyObject *PyThreadState_GetDict()
  반환값: 빌린 참조. Part of the 안정 ABI.

  Return a dictionary in which extensions can store thread-specific state information. Each extension should use a unique key to use to store state in the dictionary. It is okay to call this function when no thread state is attached. If this function returns `NULL`, no exception has been raised and the caller should assume no thread state is attached.

int PyThreadState_SetAsyncExc(unsigned long id, PyObject *exc)
  Part of the 안정 ABI.

  Asynchronously raise an exception in a thread. The id argument is the thread id of the target thread; exc is the exception object to be raised. This function does not steal any references to exc. To prevent naive misuse, you must write your own C extension to call this. Must be called with an attached thread state. Returns the number of thread states modified; this is normally one, but will be zero if the thread id isn’t found. If exc is `NULL`, the pending exception (if any) for the thread is cleared. This raises no exceptions.

  버전 3.7에서 변경: The type of the id parameter changed from long to unsigned long.

void PyEval_AcquireThread(PyThreadState *tstate)
  Part of the 안정 ABI.

  Attach tstate to the current thread, which must not be `NULL` or already attached.

  The calling thread must not already have an attached thread state.

  참고

  Calling this function from a thread when the runtime is finalizing will hang the thread until the program exits, even if the thread was not created by Python. Refer to Cautions regarding runtime finalization for more details.

  버전 3.8에서 변경: `PyEval_RestoreThread()`, `Py_END_ALLOW_THREADS()` 및 `PyGILState_Ensure()`와 일관되도록 갱신되었으며, 인터프리터가 파이널리제이션 하는 동안 호출되면 현재 스레드를 종료합니다.

  버전 3.14에서 변경: Hangs the current thread, rather than terminating it, if called while the interpreter is finalizing.

  `PyEval_RestoreThread()`는 (스레드가 초기화되지 않았을 때조차) 항상 사용할 수 있는 고수준 함수입니다.

void PyEval_ReleaseThread(PyThreadState *tstate)
  Part of the 안정 ABI.

  Detach the attached thread state. The tstate argument, which must not be `NULL`, is only used to check that it represents the attached thread state — if it isn’t, a fatal error is reported.

  `PyEval_SaveThread()`는 (스레드가 초기화되지 않은 경우에조차) 항상 사용할 수 있는 고수준 함수입니다.

## 서브 인터프리터 지원

대부분의 경우, 단일 파이썬 인터프리터만 내장할 것입니다만, 같은 프로세스, 어쩌면 같은 스레드에서 여러 독립 인터프리터를 만들어야 하는 경우가 있습니다. 서브 인터프리터는 그렇게 할 수 있도록 합니다.

“메인” 인터프리터는 런타임이 초기화될 때 만들어지는 첫 번째 인터프리터입니다. 보통은 프로세스에서 유일한 파이썬 인터프리터입니다. 서브 인터프리터와 달리, 메인 인터프리터는 시그널 처리와 같은 고유한 프로세스 전역 책임을 갖습니다. 또한 런타임 초기화 동안 실행을 담당하며 일반적으로 런타임 파이널리제이션 동안 활성 인터프리터입니다. `PyInterpreterState_Main()` 함수는 그것의 상태에 대한 포인터를 반환합니다.

`PyThreadState_Swap()` 함수를 사용하여 서브 인터프리터 간에 전환할 수 있습니다. 다음 함수를 사용하여 만들고 파괴할 수 있습니다:

type PyInterpreterConfig

  Structure containing most parameters to configure a sub-interpreter. Its values are used only in `Py_NewInterpreterFromConfig()` and never modified by the runtime.

  Added in version 3.12.

  Structure fields:

  int use_main_obmalloc

    If this is `0` then the sub-interpreter will use its own “object” allocator state. Otherwise it will use (share) the main interpreter’s.

    If this is `0` then `check_multi_interp_extensions` must be `1` (non-zero). If this is `1` then `gil` must not be `PyInterpreterConfig_OWN_GIL`.

  int allow_fork

    If this is `0` then the runtime will not support forking the process in any thread where the sub-interpreter is currently active. Otherwise fork is unrestricted.

    Note that the `subprocess` module still works when fork is disallowed.

  int allow_exec

    If this is `0` then the runtime will not support replacing the current process via exec (e.g. `os.execv()`) in any thread where the sub-interpreter is currently active. Otherwise exec is unrestricted.

    Note that the `subprocess` module still works when exec is disallowed.

  int allow_threads

    If this is `0` then the sub-interpreter’s `threading` module won’t create threads. Otherwise threads are allowed.

  int allow_daemon_threads

    If this is `0` then the sub-interpreter’s `threading` module won’t create daemon threads. Otherwise daemon threads are allowed (as long as `allow_threads` is non-zero).

  int check_multi_interp_extensions

    If this is `0` then all extension modules may be imported, including legacy (single-phase init) modules, in any thread where the sub-interpreter is currently active. Otherwise only multi-phase init extension modules (see PEP 489) may be imported. (Also see `Py_mod_multiple_interpreters`.)

    This must be `1` (non-zero) if `use_main_obmalloc` is `0`.

  int gil

    This determines the operation of the GIL for the sub-interpreter. It may be one of the following:

    PyInterpreterConfig_DEFAULT_GIL

      Use the default selection (`PyInterpreterConfig_SHARED_GIL`).

    PyInterpreterConfig_SHARED_GIL

      Use (share) the main interpreter’s GIL.

    PyInterpreterConfig_OWN_GIL

      Use the sub-interpreter’s own GIL.

    If this is `PyInterpreterConfig_OWN_GIL` then `PyInterpreterConfig.use_main_obmalloc` must be `0`.

PyStatus Py_NewInterpreterFromConfig(PyThreadState **tstate_p, const PyInterpreterConfig *config)

  새 서브 인터프리터를 만듭니다. 이것은 파이썬 코드 실행을 위한 (거의) 완전히 분리된 환경입니다. 특히, 새 인터프리터에는 기본 모듈 `builtins`, `__main__` 및 `sys`를 포함하여, 모든 임포트 된 모듈의 개별, 독립 버전을 갖습니다. 로드된 모듈 테이블(`sys.modules`)과 모듈 검색 경로(`sys.path`)도 별개입니다. 새 환경에는 `sys.argv` 변수가 없습니다. 새로운 표준 I/O 스트림 파일 객체 `sys.stdin`, `sys.stdout` 및 `sys.stderr`을 갖습니다 (단, 같은 하부 파일 기술자를 참조합니다).

  The given config controls the options with which the interpreter is initialized.

  Upon success, tstate_p will be set to the first thread state created in the new sub-interpreter. This thread state is attached. Note that no actual thread is created; see the discussion of thread states below. If creation of the new interpreter is unsuccessful, tstate_p is set to `NULL`; no exception is set since the exception state is stored in the attached thread state, which might not exist.

  Like all other Python/C API functions, an attached thread state must be present before calling this function, but it might be detached upon returning. On success, the returned thread state will be attached. If the sub-interpreter is created with its own GIL then the attached thread state of the calling interpreter will be detached. When the function returns, the new interpreter’s thread state will be attached to the current thread and the previous interpreter’s attached thread state will remain detached.

  Added in version 3.12.

  Sub-interpreters are most effective when isolated from each other, with certain functionality restricted:

      PyInterpreterConfig config = {
          .use_main_obmalloc = 0,
          .allow_fork = 0,
          .allow_exec = 0,
          .allow_threads = 1,
          .allow_daemon_threads = 0,
          .check_multi_interp_extensions = 1,
          .gil = PyInterpreterConfig_OWN_GIL,
      };
      PyThreadState *tstate = NULL;
      PyStatus status = Py_NewInterpreterFromConfig(&tstate, &config);
      if (PyStatus_Exception(status)) {
          Py_ExitStatusException(status);
      }

  Note that the config is used only briefly and does not get modified. During initialization the config’s values are converted into various `PyInterpreterState` values. A read-only copy of the config may be stored internally on the `PyInterpreterState`.

  확장 모듈은 다음과 같이 (서브) 인터프리터 간에 공유됩니다:

  - 다단계 초기화를 사용하는 모듈의 경우, 예를 들어 `PyModule_FromDefAndSpec()`, 각 인터프리터에 대해 별도의 모듈 객체가 만들어지고 초기화됩니다. C 수준 정적과 전역 변수만 이러한 모듈 객체 간에 공유됩니다.

  - For modules using legacy single-phase initialization, e.g. `PyModule_Create()`, the first time a particular extension is imported, it is initialized normally, and a (shallow) copy of its module’s dictionary is squirreled away. When the same extension is imported by another (sub-)interpreter, a new module is initialized and filled with the contents of this copy; the extension’s `init` function is not called. Objects in the module’s dictionary thus end up shared across (sub-)interpreters, which might cause unwanted behavior (see Bugs and caveats below).

    이것은 인터프리터가 `Py_FinalizeEx()`와 `Py_Initialize()`를 호출하여 완전히 다시 초기화된 후 확장을 임포트 할 때 일어나는 것과 다름에 유의하십시오; 이 경우, 확장의 `initmodule` 함수가 다시 호출됩니다. 다단계 초기화와 마찬가지로, 이는 C 수준의 정적과 전역 변수만 이러한 모듈 간에 공유됨을 의미합니다.

PyThreadState *Py_NewInterpreter(void)
  Part of the 안정 ABI.

  Create a new sub-interpreter. This is essentially just a wrapper around `Py_NewInterpreterFromConfig()` with a config that preserves the existing behavior. The result is an unisolated sub-interpreter that shares the main interpreter’s GIL, allows fork/exec, allows daemon threads, and allows single-phase init modules.

void Py_EndInterpreter(PyThreadState *tstate)
  Part of the 안정 ABI.

  Destroy the (sub-)interpreter represented by the given thread state. The given thread state must be attached. When the call returns, there will be no attached thread state. All thread states associated with this interpreter are destroyed.

  `Py_FinalizeEx()` will destroy all sub-interpreters that haven’t been explicitly destroyed at that point.

### A Per-Interpreter GIL

Using `Py_NewInterpreterFromConfig()` you can create a sub-interpreter that is completely isolated from other interpreters, including having its own GIL. The most important benefit of this isolation is that such an interpreter can execute Python code without being blocked by other interpreters or blocking any others. Thus a single Python process can truly take advantage of multiple CPU cores when running Python code. The isolation also encourages a different approach to concurrency than that of just using threads. (See PEP 554 and PEP 684.)

Using an isolated interpreter requires vigilance in preserving that isolation. That especially means not sharing any objects or mutable state without guarantees about thread-safety. Even objects that are otherwise immutable (e.g. `None`, `(1, 5)`) can’t normally be shared because of the refcount. One simple but less-efficient approach around this is to use a global lock around all use of some state (or object). Alternately, effectively immutable objects (like integers or strings) can be made safe in spite of their refcounts by making them immortal. In fact, this has been done for the builtin singletons, small integers, and a number of other builtin objects.

If you preserve isolation then you will have access to proper multi-core computing without the complications that come with free-threading. Failure to preserve isolation will expose you to the full consequences of free-threading, including races and hard-to-debug crashes.

Aside from that, one of the main challenges of using multiple isolated interpreters is how to communicate between them safely (not break isolation) and efficiently. The runtime and stdlib do not provide any standard approach to this yet. A future stdlib module would help mitigate the effort of preserving isolation and expose effective tools for communicating (and sharing) data between interpreters.

Added in version 3.12.

### 버그와 주의 사항

서브 인터프리터(및 메인 인터프리터)는 같은 프로세스의 일부이기 때문에, 그들 간의 절연이 완벽하지 않습니다 — 예를 들어, `os.close()`와 같은 저수준 파일 연산을 사용하면 서로의 열린 파일에 (실수로 혹은 악의적으로) 영향을 미칠 수 있습니다. (서브) 인터프리터 간에 확장이 공유되는 방식 때문에, 일부 확장이 제대로 작동하지 않을 수 있습니다; 이것은 특히 단단계 초기화나 (정적) 전역 변수를 사용할 때 특히 그렇습니다. 한 서브 인터프리터에서 만든 객체를 다른 (서브) 인터프리터의 이름 공간에 삽입할 수 있습니다; 가능하면 피해야 합니다.

서브 인터프리터 간에 사용자 정의 함수, 메서드, 인스턴스 또는 클래스를 공유하지 않도록 특별한 주의를 기울여야 합니다. 이러한 객체에 의해 실행되는 임포트 연산은 잘못된 (서브) 인터프리터의 로드된 모듈 딕셔너리에 영향을 미칠 수 있기 때문입니다. 위의 것들에서 접근할 수 있는 객체를 공유하지 않는 것도 마찬가지로 중요합니다.

Also note that combining this functionality with `PyGILState_*` APIs is delicate, because these APIs assume a bijection between Python thread states and OS-level threads, an assumption broken by the presence of sub-interpreters. It is highly recommended that you don’t switch sub-interpreters between a pair of matching `PyGILState_Ensure()` and `PyGILState_Release()` calls. Furthermore, extensions (such as `ctypes`) using these APIs to allow calling of Python code from non-Python created threads will probably be broken when using sub-interpreters.

## 비동기 알림

메인 인터프리터 스레드에 비동기 알림을 보내는 메커니즘이 제공됩니다. 이러한 알림은 함수 포인터와 void 포인터 인자의 형태를 취합니다.

int Py_AddPendingCall(int (*func)(void*), void *arg)
  Part of the 안정 ABI.

  메인 인터프리터 스레드에서 호출할 함수를 예약합니다. 성공하면 `0`이 반환되고 func는 메인 스레드에서 호출되기 위해 큐에 추가됩니다. 실패 시, 예외 설정 없이 `-1`이 반환됩니다.

  성공적으로 큐에 넣으면, func는 arg 인자를 사용하여 결국 메인 인터프리터 스레드에서 호출됩니다. 정상적으로 실행되는 파이썬 코드와 비교할 때 비동기적으로 호출되지만, 다음 두 조건이 모두 충족됩니다:

  - 바이트 코드 경계에서;

  - with the main thread holding an attached thread state (func can therefore use the full C API).

  func must return `0` on success, or `-1` on failure with an exception set. func won’t be interrupted to perform another asynchronous notification recursively, but it can still be interrupted to switch threads if the thread state is detached.

  This function doesn’t need an attached thread state. However, to call this function in a subinterpreter, the caller must have an attached thread state. Otherwise, the function func can be scheduled to be called from the wrong interpreter.

  경고

  이것은 매우 특별한 경우에만 유용한, 저수준 함수입니다. func가 가능한 한 빨리 호출된다는 보장은 없습니다. 메인 스레드가 시스템 호출을 실행 중이라 바쁘면, 시스템 호출이 반환되기 전에 func가 호출되지 않습니다. 이 함수는 일반적으로 임의의 C 스레드에서 파이썬 코드를 호출하는 데 적합하지 않습니다. 대신, PyGILState API를 사용하십시오.

  Added in version 3.1.

  버전 3.9에서 변경: 이 함수가 서브 인터프리터에서 호출되면, func 함수는 이제 메인 인터프리터에서 호출되지 않고 서브 인터프리터에서 호출되도록 예약됩니다. 이제 각 서브 인터프리터는 자체 예약된 호출 목록을 갖습니다.

  버전 3.12에서 변경: This function now always schedules func to be run in the main interpreter.

int Py_MakePendingCalls(void)
  Part of the 안정 ABI.

  Execute all pending calls. This is usually executed automatically by the interpreter.

  This function returns `0` on success, and returns `-1` with an exception set on failure.

  If this is not called in the main thread of the main interpreter, this function does nothing and returns `0`. The caller must hold an attached thread state.

  Added in version 3.1.

  버전 3.12에서 변경: This function only runs pending calls in the main interpreter.

## 프로파일링과 추적

파이썬 인터프리터는 프로파일링과 실행 추적 기능을 연결하기 위한 몇 가지 저수준 지원을 제공합니다. 프로파일링, 디버깅 및 커버리지 분석 도구에 사용됩니다.

이 C 인터페이스를 사용하면 프로파일링이나 추적 코드가 파이썬 수준의 콜러블 객체를 통해 호출하는 오버헤드를 피하고, 대신 직접 C 함수를 호출할 수 있습니다. 시설의 필수 어트리뷰트는 변경되지 않았습니다; 인터페이스는 추적 함수를 스레드별로 설치할 수 있도록 하며, 추적 함수에 보고되는 기본 이벤트는 이전 버전의 파이썬 수준 추적 함수에 보고된 것과 같습니다.

typedef int (*Py_tracefunc)(PyObject *obj, PyFrameObject *frame, int what, PyObject *arg)

  The type of the trace function registered using `PyEval_SetProfile()` and `PyEval_SetTrace()`. The first parameter is the object passed to the registration function as obj, frame is the frame object to which the event pertains, what is one of the constants `PyTrace_CALL`, `PyTrace_EXCEPTION`, `PyTrace_LINE`, `PyTrace_RETURN`, `PyTrace_C_CALL`, `PyTrace_C_EXCEPTION`, `PyTrace_C_RETURN`, or `PyTrace_OPCODE`, and arg depends on the value of what:

  what의 값 | arg의 의미
  --- | ---
  `PyTrace_CALL` | 항상 `Py_None`.
  `PyTrace_EXCEPTION` | `sys.exc_info()`에서 반환된 예외 정보.
  `PyTrace_LINE` | 항상 `Py_None`.
  `PyTrace_RETURN` | 호출자에게 반환되는 값, 또는 예외로 인한 것이면 `NULL`.
  `PyTrace_C_CALL` | 호출되는 함수 객체.
  `PyTrace_C_EXCEPTION` | 호출되는 함수 객체.
  `PyTrace_C_RETURN` | 호출되는 함수 객체.
  `PyTrace_OPCODE` | 항상 `Py_None`.

int PyTrace_CALL

  함수나 메서드에 대한 새 호출이 보고되거나, 제너레이터에 대한 새 항목이 보고될 때 `Py_tracefunc` 함수에 대한 what 매개 변수의 값. 제너레이터 함수에 대한 이터레이터의 생성은 해당 프레임의 파이썬 바이트 코드로의 제어 전송이 없기 때문에 보고되지 않음에 유의하십시오.

int PyTrace_EXCEPTION

  예외가 발생했을 때 `Py_tracefunc` 함수에 대한 what 매개 변수의 값. 콜백 함수는 실행되는 프레임 내에서 바이트 코드가 처리된 후 예외가 설정될 때 what에 대해 이 값으로 호출됩니다. 이것의 효과는 예외 전파로 인해 파이썬 스택이 되감기는 것입니다, 예외가 전파되어 각 프레임으로 반환할 때 콜백이 호출됩니다. 추적 함수만 이러한 이벤트를 수신합니다; 프로파일러에는 필요하지 않습니다.

int PyTrace_LINE

  The value passed as the what parameter to a `Py_tracefunc` function (but not a profiling function) when a line-number event is being reported. It may be disabled for a frame by setting `f_trace_lines` to 0 on that frame.

int PyTrace_RETURN

  호출이 반환되려고 할 때 `Py_tracefunc` 함수에 대한 what 매개 변수의 값.

int PyTrace_C_CALL

  C 함수가 호출되려고 할 때 `Py_tracefunc` 함수에 대한 what 매개 변수의 값.

int PyTrace_C_EXCEPTION

  C 함수에서 예외가 발생했을 때 `Py_tracefunc` 함수에 대한 what 매개 변수의 값.

int PyTrace_C_RETURN

  C 함수가 반환했을 때 `Py_tracefunc` 함수에 대한 what 매개 변수의 값.

int PyTrace_OPCODE

  The value for the what parameter to `Py_tracefunc` functions (but not profiling functions) when a new opcode is about to be executed. This event is not emitted by default: it must be explicitly requested by setting `f_trace_opcodes` to 1 on the frame.

void PyEval_SetProfile(Py_tracefunc func, PyObject *obj)

  Set the profiler function to func. The obj parameter is passed to the function as its first parameter, and may be any Python object, or `NULL`. If the profile function needs to maintain state, using a different value for obj for each thread provides a convenient and thread-safe place to store it. The profile function is called for all monitored events except `PyTrace_LINE` `PyTrace_OPCODE` and `PyTrace_EXCEPTION`.

  See also the `sys.setprofile()` function.

  The caller must have an attached thread state.

void PyEval_SetProfileAllThreads(Py_tracefunc func, PyObject *obj)

  Like `PyEval_SetProfile()` but sets the profile function in all running threads belonging to the current interpreter instead of the setting it only on the current thread.

  The caller must have an attached thread state.

  As `PyEval_SetProfile()`, this function ignores any exceptions raised while setting the profile functions in all threads.

Added in version 3.12.

void PyEval_SetTrace(Py_tracefunc func, PyObject *obj)

  Set the tracing function to func. This is similar to `PyEval_SetProfile()`, except the tracing function does receive line-number events and per-opcode events, but does not receive any event related to C function objects being called. Any trace function registered using `PyEval_SetTrace()` will not receive `PyTrace_C_CALL`, `PyTrace_C_EXCEPTION` or `PyTrace_C_RETURN` as a value for the what parameter.

  See also the `sys.settrace()` function.

  The caller must have an attached thread state.

void PyEval_SetTraceAllThreads(Py_tracefunc func, PyObject *obj)

  Like `PyEval_SetTrace()` but sets the tracing function in all running threads belonging to the current interpreter instead of the setting it only on the current thread.

  The caller must have an attached thread state.

  As `PyEval_SetTrace()`, this function ignores any exceptions raised while setting the trace functions in all threads.

Added in version 3.12.

## Reference tracing

Added in version 3.13.

typedef int (*PyRefTracer)(PyObject*, int event, void *data)

  The type of the trace function registered using `PyRefTracer_SetTracer()`. The first parameter is a Python object that has been just created (when event is set to `PyRefTracer_CREATE`) or about to be destroyed (when event is set to `PyRefTracer_DESTROY`). The data argument is the opaque pointer that was provided when `PyRefTracer_SetTracer()` was called.

  If a new tracing function is registered replacing the current a call to the trace function will be made with the object set to NULL and event set to `PyRefTracer_TRACKER_REMOVED`. This will happen just before the new function is registered.

Added in version 3.13.

int PyRefTracer_CREATE

  The value for the event parameter to `PyRefTracer` functions when a Python object has been created.

int PyRefTracer_DESTROY

  The value for the event parameter to `PyRefTracer` functions when a Python object has been destroyed.

int PyRefTracer_TRACKER_REMOVED

  The value for the event parameter to `PyRefTracer` functions when the current tracer is about to be replaced by a new one.

  Added in version 3.14.

int PyRefTracer_SetTracer(PyRefTracer tracer, void *data)

  Register a reference tracer function. The function will be called when a new Python has been created or when an object is going to be destroyed. If data is provided it must be an opaque pointer that will be provided when the tracer function is called. Return `0` on success. Set an exception and return `-1` on error.

  Not that tracer functions must not create Python objects inside or otherwise the call will be re-entrant. The tracer also must not clear any existing exception or set an exception. A thread state will be active every time the tracer function is called.

  There must be an attached thread state when calling this function.

  If another tracer function was already registered, the old function will be called with event set to `PyRefTracer_TRACKER_REMOVED` just before the new function is registered.

Added in version 3.13.

PyRefTracer PyRefTracer_GetTracer(void **data)

  Get the registered reference tracer function and the value of the opaque data pointer that was registered when `PyRefTracer_SetTracer()` was called. If no tracer was registered this function will return NULL and will set the data pointer to NULL.

  There must be an attached thread state when calling this function.

Added in version 3.13.

## 고급 디버거 지원

이 함수들은 고급 디버깅 도구에서만 사용하기 위한 것입니다.

PyInterpreterState *PyInterpreterState_Head()

  인터프리터 상태 객체들의 리스트의 머리에 있는 객체를 반환합니다.

PyInterpreterState *PyInterpreterState_Main()

  메인 인터프리터 상태 객체를 반환합니다.

PyInterpreterState *PyInterpreterState_Next(PyInterpreterState *interp)

  인터프리터 상태 객체들의 리스트에서 interp 이후의 다음 인터프리터 상태 객체를 반환합니다.

PyThreadState *PyInterpreterState_ThreadHead(PyInterpreterState *interp)

  인터프리터 interp와 관련된 스레드 리스트에서 첫 번째 `PyThreadState` 객체에 대한 포인터를 반환합니다.

PyThreadState *PyThreadState_Next(PyThreadState *tstate)

  같은 `PyInterpreterState` 객체에 속하는 모든 스레드 객체 리스트에서 tstate 이후의 다음 스레드 상태 객체를 반환합니다.

## 스레드 로컬 저장소 지원

The Python interpreter provides low-level support for thread-local storage (TLS) which wraps the underlying native TLS implementation to support the Python-level thread local storage API (`threading.local`). The CPython C level APIs are similar to those offered by pthreads and Windows: use a thread key and functions to associate a void* value per thread.

A thread state does not need to be attached when calling these functions; they supply their own locking.

`Python.h`에는 TLS API 선언이 포함되어 있지 않음에 유의하십시오, 스레드 로컬 저장소를 사용하려면 `pythread.h`를 포함해야 합니다.

참고

None of these API functions handle memory management on behalf of the void* values. You need to allocate and deallocate them yourself. If the void* values happen to be PyObject*, these functions don’t do refcount operations on them either.

### 스레드별 저장소 (TSS - Thread Specific Storage) API

TSS API is introduced to supersede the use of the existing TLS API within the CPython interpreter. This API uses a new type `Py_tss_t` instead of int to represent thread keys.

Added in version 3.7.

더 보기

“CPython의 스레드-로컬 저장소를 위한 새로운 C-API” (PEP 539)

type Py_tss_t

  이 자료 구조는 스레드 키의 상태를 나타내며, 정의는 하부 TLS 구현에 따라 달라질 수 있으며, 키의 초기화 상태를 나타내는 내부 필드가 있습니다. 이 구조체에는 공개 멤버가 없습니다.

  Py_LIMITED_API가 정의되지 않을 때, `Py_tss_NEEDS_INIT`로 이 형의 정적 할당이 허용됩니다.

Py_tss_NEEDS_INIT

  이 매크로는 `Py_tss_t` 변수의 초기화자(initializer)로 확장됩니다. 이 매크로는 Py_LIMITED_API에서 정의되지 않음에 유의하십시오.

#### 동적 할당

Py_LIMITED_API로 빌드된 확장 모듈에 필요한, 빌드 시점에 구현이 불투명해서 형의 정적 할당이 불가능한 `Py_tss_t`의 동적 할당.

Py_tss_t *PyThread_tss_alloc()
  Part of the 안정 ABI 버전 3.7 이후로.

  `Py_tss_NEEDS_INIT`로 초기화된 값과 같은 상태의 값을 반환하거나, 동적 할당 실패 시 `NULL`을 반환합니다.

void PyThread_tss_free(Py_tss_t *key)
  Part of the 안정 ABI 버전 3.7 이후로.

  Free the given key allocated by `PyThread_tss_alloc()`, after first calling `PyThread_tss_delete()` to ensure any associated thread locals have been unassigned. This is a no-op if the key argument is `NULL`.

  참고

  A freed key becomes a dangling pointer. You should reset the key to `NULL`.

#### 메서드

이 함수들의 매개 변수 key는 `NULL`이 아니어야 합니다. 또한, 주어진 `Py_tss_t`가 `PyThread_tss_create()`로 초기화되지 않았으면, `PyThread_tss_set()`과 `PyThread_tss_get()`의 동작은 정의되지 않습니다.

int PyThread_tss_is_created(Py_tss_t *key)
  Part of the 안정 ABI 버전 3.7 이후로.

  주어진 `Py_tss_t`가 `PyThread_tss_create()`로 초기화되었으면 0이 아닌 값을 반환합니다.

int PyThread_tss_create(Py_tss_t *key)
  Part of the 안정 ABI 버전 3.7 이후로.

  TSS 키 초기화에 성공하면 0 값을 반환합니다. key 인자가 가리키는 값이 `Py_tss_NEEDS_INIT`로 초기화되지 않으면 동작이 정의되지 않습니다. 이 함수는 같은 키에서 반복적으로 호출될 수 있습니다 – 이미 초기화된 키에 대해 호출하면 아무런 일도 하지 않으며 즉시 성공을 반환합니다.

void PyThread_tss_delete(Py_tss_t *key)
  Part of the 안정 ABI 버전 3.7 이후로.

  TSS 키를 삭제하여 모든 스레드에서 키와 관련된 값을 잊게 하고, 키의 초기화 상태를 초기화되지 않음으로 변경합니다. 파괴된 키는 `PyThread_tss_create()`로 다시 초기화할 수 있습니다. 이 함수는 같은 키에서 반복적으로 호출될 수 있습니다 – 이미 파괴된 키에 대해 호출하면 아무런 일도 하지 않습니다.

int PyThread_tss_set(Py_tss_t *key, void *value)
  Part of the 안정 ABI 버전 3.7 이후로.

  Return a zero value to indicate successfully associating a void* value with a TSS key in the current thread. Each thread has a distinct mapping of the key to a void* value.

void *PyThread_tss_get(Py_tss_t *key)
  Part of the 안정 ABI 버전 3.7 이후로.

  Return the void* value associated with a TSS key in the current thread. This returns `NULL` if no value is associated with the key in the current thread.

### 스레드 로컬 저장소 (TLS) API

버전 3.7부터 폐지됨: 이 API는 스레드별 저장소 (TSS) API로 대체됩니다.

참고

이 버전의 API는 `int`로 안전하게 캐스트 할 수 없는 방식으로 네이티브 TLS 키가 정의된 플랫폼을 지원하지 않습니다. 이러한 플랫폼에서, `PyThread_create_key()`는 실패 상태로 즉시 반환되며, 다른 TLS 함수는 이러한 플랫폼에서 모두 아무런 일도 하지 않습니다.

위에서 언급한 호환성 문제로 인해, 이 버전의 API를 새 코드에서 사용해서는 안 됩니다.

int PyThread_create_key()
  Part of the 안정 ABI.

void PyThread_delete_key(int key)
  Part of the 안정 ABI.

int PyThread_set_key_value(int key, void *value)
  Part of the 안정 ABI.

void *PyThread_get_key_value(int key)
  Part of the 안정 ABI.

void PyThread_delete_key_value(int key)
  Part of the 안정 ABI.

void PyThread_ReInitTLS()
  Part of the 안정 ABI.

## Synchronization Primitives

The C-API provides a basic mutual exclusion lock.

type PyMutex

  A mutual exclusion lock. The `PyMutex` should be initialized to zero to represent the unlocked state. For example:

      PyMutex mutex = {0};

  Instances of `PyMutex` should not be copied or moved. Both the contents and address of a `PyMutex` are meaningful, and it must remain at a fixed, writable location in memory.

  참고

  A `PyMutex` currently occupies one byte, but the size should be considered unstable. The size may change in future Python releases without a deprecation period.

  Added in version 3.13.

void PyMutex_Lock(PyMutex *m)

  Lock mutex m. If another thread has already locked it, the calling thread will block until the mutex is unlocked. While blocked, the thread will temporarily detach the thread state if one exists.

  Added in version 3.13.

void PyMutex_Unlock(PyMutex *m)

  Unlock mutex m. The mutex must be locked — otherwise, the function will issue a fatal error.

  Added in version 3.13.

int PyMutex_IsLocked(PyMutex *m)

  Returns non-zero if the mutex m is currently locked, zero otherwise.

  참고

  This function is intended for use in assertions and debugging only and should not be used to make concurrency control decisions, as the lock state may change immediately after the check.

  Added in version 3.14.

### Python Critical Section API

The critical section API provides a deadlock avoidance layer on top of per-object locks for free-threaded CPython. They are intended to replace reliance on the global interpreter lock, and are no-ops in versions of Python with the global interpreter lock.

Critical sections are intended to be used for custom types implemented in C-API extensions. They should generally not be used with built-in types like `list` and `dict` because their public C-APIs already use critical sections internally, with the notable exception of `PyDict_Next()`, which requires critical section to be acquired externally.

Critical sections avoid deadlocks by implicitly suspending active critical sections, hence, they do not provide exclusive access such as provided by traditional locks like `PyMutex`. When a critical section is started, the per-object lock for the object is acquired. If the code executed inside the critical section calls C-API functions then it can suspend the critical section thereby releasing the per-object lock, so other threads can acquire the per-object lock for the same object.

Variants that accept `PyMutex` pointers rather than Python objects are also available. Use these variants to start a critical section in a situation where there is no `PyObject` – for example, when working with a C type that does not extend or wrap `PyObject` but still needs to call into the C API in a manner that might lead to deadlocks.

The functions and structs used by the macros are exposed for cases where C macros are not available. They should only be used as in the given macro expansions. Note that the sizes and contents of the structures may change in future Python versions.

참고

Operations that need to lock two objects at once must use `Py_BEGIN_CRITICAL_SECTION2`. You cannot use nested critical sections to lock more than one object at once, because the inner critical section may suspend the outer critical sections. This API does not provide a way to lock more than two objects at once.

Example usage:

    static PyObject *
    set_field(MyObject *self, PyObject *value)
    {
       Py_BEGIN_CRITICAL_SECTION(self);
       Py_SETREF(self->field, Py_XNewRef(value));
       Py_END_CRITICAL_SECTION();
       Py_RETURN_NONE;
    }

In the above example, `Py_SETREF` calls `Py_DECREF`, which can call arbitrary code through an object’s deallocation function. The critical section API avoids potential deadlocks due to reentrancy and lock ordering by allowing the runtime to temporarily suspend the critical section if the code triggered by the finalizer blocks and calls `PyEval_SaveThread()`.

Py_BEGIN_CRITICAL_SECTION(op)

  Acquires the per-object lock for the object op and begins a critical section.

  In the free-threaded build, this macro expands to:

      {
          PyCriticalSection _py_cs;
          PyCriticalSection_Begin(&_py_cs, (PyObject*)(op))

  In the default build, this macro expands to `{`.

  Added in version 3.13.

Py_BEGIN_CRITICAL_SECTION_MUTEX(m)

  Locks the mutex m and begins a critical section.

  In the free-threaded build, this macro expands to:

      {
           PyCriticalSection _py_cs;
           PyCriticalSection_BeginMutex(&_py_cs, m)

  Note that unlike `Py_BEGIN_CRITICAL_SECTION`, there is no cast for the argument of the macro - it must be a `PyMutex` pointer.

  On the default build, this macro expands to `{`.

  Added in version 3.14.

Py_END_CRITICAL_SECTION()

  Ends the critical section and releases the per-object lock.

  In the free-threaded build, this macro expands to:

          PyCriticalSection_End(&_py_cs);
      }

  In the default build, this macro expands to `}`.

  Added in version 3.13.

Py_BEGIN_CRITICAL_SECTION2(a, b)

  Acquires the per-objects locks for the objects a and b and begins a critical section. The locks are acquired in a consistent order (lowest address first) to avoid lock ordering deadlocks.

  In the free-threaded build, this macro expands to:

      {
          PyCriticalSection2 _py_cs2;
          PyCriticalSection2_Begin(&_py_cs2, (PyObject*)(a), (PyObject*)(b))

  In the default build, this macro expands to `{`.

  Added in version 3.13.

Py_BEGIN_CRITICAL_SECTION2_MUTEX(m1, m2)

  Locks the mutexes m1 and m2 and begins a critical section.

  In the free-threaded build, this macro expands to:

      {
           PyCriticalSection2 _py_cs2;
           PyCriticalSection2_BeginMutex(&_py_cs2, m1, m2)

  Note that unlike `Py_BEGIN_CRITICAL_SECTION2`, there is no cast for the arguments of the macro - they must be `PyMutex` pointers.

  On the default build, this macro expands to `{`.

  Added in version 3.14.

Py_END_CRITICAL_SECTION2()

  Ends the critical section and releases the per-object locks.

  In the free-threaded build, this macro expands to:

          PyCriticalSection2_End(&_py_cs2);
      }

  In the default build, this macro expands to `}`.

  Added in version 3.13.

### Legacy Locking APIs

These APIs are obsolete since Python 3.13 with the introduction of `PyMutex`.

버전 3.15에서 변경: These APIs are now a simple wrapper around `PyMutex`.

type PyThread_type_lock

  A pointer to a mutual exclusion lock.

type PyLockStatus

  The result of acquiring a lock with a timeout.

  enumerator PY_LOCK_FAILURE

    Failed to acquire the lock.

  enumerator PY_LOCK_ACQUIRED

    The lock was successfully acquired.

  enumerator PY_LOCK_INTR

    The lock was interrupted by a signal.

PyThread_type_lock PyThread_allocate_lock(void)
  Part of the 안정 ABI.

  Allocate a new lock.

  On success, this function returns a lock; on failure, this function returns `0` without an exception set.

  The caller does not need to hold an attached thread state.

  버전 3.15에서 변경: This function now always uses `PyMutex`. In prior versions, this would use a lock provided by the operating system.

void PyThread_free_lock(PyThread_type_lock lock)
  Part of the 안정 ABI.

  Destroy lock. The lock should not be held by any thread when calling this.

  The caller does not need to hold an attached thread state.

PyLockStatus PyThread_acquire_lock_timed(PyThread_type_lock lock, long long microseconds, int intr_flag)
  Part of the 안정 ABI.

  Acquire lock with a timeout.

  This will wait for microseconds microseconds to acquire the lock. If the timeout expires, this function returns `PY_LOCK_FAILURE`. If microseconds is `-1`, this will wait indefinitely until the lock has been released.

  If intr_flag is `1`, acquiring the lock may be interrupted by a signal, in which case this function returns `PY_LOCK_INTR`. Upon interruption, it’s generally expected that the caller makes a call to `Py_MakePendingCalls()` to propagate an exception to Python code.

  If the lock is successfully acquired, this function returns `PY_LOCK_ACQUIRED`.

  The caller does not need to hold an attached thread state.

int PyThread_acquire_lock(PyThread_type_lock lock, int waitflag)
  Part of the 안정 ABI.

  Acquire lock.

  If waitflag is `1` and another thread currently holds the lock, this function will wait until the lock can be acquired and will always return `1`.

  If waitflag is `0` and another thread holds the lock, this function will not wait and instead return `0`. If the lock is not held by any other thread, then this function will acquire it and return `1`.

  Unlike `PyThread_acquire_lock_timed()`, acquiring the lock cannot be interrupted by a signal.

  The caller does not need to hold an attached thread state.

int PyThread_release_lock(PyThread_type_lock lock)
  Part of the 안정 ABI.

  Release lock. If lock is not held, then this function issues a fatal error.

  The caller does not need to hold an attached thread state.

## Operating System Thread APIs

PYTHREAD_INVALID_THREAD_ID

  Sentinel value for an invalid thread ID.

  This is currently equivalent to `(unsigned long)-1`.

unsigned long PyThread_start_new_thread(void (*func)(void*), void *arg)
  Part of the 안정 ABI.

  Start function func in a new thread with argument arg. The resulting thread is not intended to be joined.

  func must not be `NULL`, but arg may be `NULL`.

  On success, this function returns the identifier of the new thread; on failure, this returns `PYTHREAD_INVALID_THREAD_ID`.

  The caller does not need to hold an attached thread state.

unsigned long PyThread_get_thread_ident(void)
  Part of the 안정 ABI.

  Return the identifier of the current thread, which will never be zero.

  This function cannot fail, and the caller does not need to hold an attached thread state.

  더 보기

  `threading.get_ident()`

PyObject *PyThread_GetInfo(void)
  Part of the 안정 ABI 버전 3.3 이후로.

  Get general information about the current thread in the form of a struct sequence object. This information is accessible as `sys.thread_info` in Python.

  On success, this returns a new strong reference to the thread information; on failure, this returns `NULL` with an exception set.

  The caller must hold an attached thread state.

PY_HAVE_THREAD_NATIVE_ID

  This macro is defined when the system supports native thread IDs.

unsigned long PyThread_get_thread_native_id(void)
  Part of the 안정 ABI on platforms with native thread IDs.

  Get the native identifier of the current thread as it was assigned by the operating system’s kernel, which will never be less than zero.

  This function is only available when `PY_HAVE_THREAD_NATIVE_ID` is defined.

  This function cannot fail, and the caller does not need to hold an attached thread state.

  더 보기

  `threading.get_native_id()`

void PyThread_exit_thread(void)
  Part of the 안정 ABI.

  Terminate the current thread. This function is generally considered unsafe and should be avoided. It is kept solely for backwards compatibility.

  This function is only safe to call if all functions in the full call stack are written to safely allow it.

  경고

  If the current system uses POSIX threads (also known as “pthreads”), this calls pthread_exit(3), which attempts to unwind the stack and call C++ destructors on some libc implementations. However, if a `noexcept` function is reached, it may terminate the process. Other systems, such as macOS, do unwinding.

  On Windows, this function calls `_endthreadex()`, which kills the thread without calling C++ destructors.

  In any case, there is a risk of corruption on the thread’s stack.

  버전 3.14부터 폐지됨.

void PyThread_init_thread(void)
  Part of the 안정 ABI.

  Initialize `PyThread*` APIs. Python executes this function automatically, so there’s little need to call it from an extension module.

int PyThread_set_stacksize(size_t size)
  Part of the 안정 ABI.

  Set the stack size of the current thread to size bytes.

  This function returns `0` on success, `-1` if size is invalid, or `-2` if the system does not support changing the stack size. This function does not set exceptions.

  The caller does not need to hold an attached thread state.

size_t PyThread_get_stacksize(void)
  Part of the 안정 ABI.

  Return the stack size of the current thread in bytes, or `0` if the system’s default stack size is in use.

  The caller does not need to hold an attached thread state.