Python 初始化配置 ¶

Added in version 3.8.

可以初始化 Python 采用 Py_InitializeFromConfig() 和 PyConfig 结构。可以预初始化它采用 Py_PreInitialize() 和 PyPreConfig 结构。

有 2 种配置：

The Python 配置 can be used to build a customized Python which behaves as the regular Python. For example, environment variables and command line arguments are used to configure Python.
The 隔离配置 can be used to embed Python into an application. It isolates Python from the system. For example, environment variables are ignored, the LC_CTYPE locale is left unchanged and no signal handler is registered.

The Py_RunMain() 函数可以用于编写定制 Python 程序。

另请参阅初始化、定稿和线程 .

另请参阅

PEP 587 Python 初始化配置。

范例 ¶

Example of customized Python always running in isolated mode:

int main(int argc, char **argv)
{
    PyStatus status;
    PyConfig config;
    PyConfig_InitPythonConfig(&config);
    config.isolated = 1;
    /* Decode command line arguments.
       Implicitly preinitialize Python (in isolated mode). */
    status = PyConfig_SetBytesArgv(&config, argc, argv);
    if (PyStatus_Exception(status)) {
        goto exception;
    }
    status = Py_InitializeFromConfig(&config);
    if (PyStatus_Exception(status)) {
        goto exception;
    }
    PyConfig_Clear(&config);
    return Py_RunMain();
exception:
    PyConfig_Clear(&config);
    if (PyStatus_IsExit(status)) {
        return status.exitcode;
    }
    /* Display the error message and exit the process with
       non-zero exit code */
    Py_ExitStatusException(status);
}

PyWideStringList ¶

type PyWideStringList ¶

List of wchar_t* strings.

若 length 非 0，项 must be non- NULL and all strings must be non- NULL .

Methods:

PyStatus PyWideStringList_Append ( PyWideStringList * list , const wchar_t * item ) ¶

追加 item to list .

Python must be preinitialized to call this function.

PyStatus PyWideStringList_Insert ( PyWideStringList * list , Py_ssize_t index , const wchar_t * item ) ¶

插入 item into list at index .

若 index >= list length, append item to list .

index must be greater than or equal to 0 .

Python must be preinitialized to call this function.

Structure fields:

Py_ssize_t length ¶: List length.

wchar_t * * items ¶: List items.

PyStatus ¶

type PyStatus ¶

Structure to store an initialization function status: success, error or exit.

For an error, it can store the C function name which created the error.

Structure fields:

int exitcode ¶: Exit code. Argument passed to exit() .

const char * err_msg ¶: Error message.

const char * func ¶: Name of the function which created an error, can be NULL .

Functions to create a status:

PyStatus PyStatus_Ok ( void ) ¶: Success.

PyStatus PyStatus_Error ( const char * err_msg ) ¶

Initialization error with a message.

err_msg 不得为 NULL .

PyStatus PyStatus_NoMemory ( void ) ¶: Memory allocation failure (out of memory).

PyStatus PyStatus_Exit ( int exitcode ) ¶: Exit Python with the specified exit code.

Functions to handle a status:

int PyStatus_Exception ( PyStatus status ) ¶: Is the status an error or an exit? If true, the exception must be handled; by calling Py_ExitStatusException() 例如。

int PyStatus_IsError ( PyStatus status ) ¶: Is the result an error?

int PyStatus_IsExit ( PyStatus status ) ¶: Is the result an exit?

void Py_ExitStatusException ( PyStatus status ) ¶: 调用 exit(exitcode) if status is an exit. Print the error message and exit with a non-zero exit code if status is an error. Must only be called if PyStatus_Exception(status) is non-zero.

注意

Internally, Python uses macros which set PyStatus.func , whereas functions to create a status set func to NULL .

范例：

PyStatus alloc(void **ptr, size_t size)
{
    *ptr = PyMem_RawMalloc(size);
    if (*ptr == NULL) {
        return PyStatus_NoMemory();
    }
    return PyStatus_Ok();
}
int main(int argc, char **argv)
{
    void *ptr;
    PyStatus status = alloc(&ptr, 16);
    if (PyStatus_Exception(status)) {
        Py_ExitStatusException(status);
    }
    PyMem_Free(ptr);
    return 0;
}

PyPreConfig ¶

type PyPreConfig ¶

Structure used to preinitialize Python.

Function to initialize a preconfiguration:

void PyPreConfig_InitPythonConfig ( PyPreConfig * preconfig ) ¶: Initialize the preconfiguration with Python 配置 .

void PyPreConfig_InitIsolatedConfig ( PyPreConfig * preconfig ) ¶: Initialize the preconfiguration with 隔离配置 .

Structure fields:

int allocator ¶

Name of the Python memory allocators:

PYMEM_ALLOCATOR_NOT_SET ( 0 ): don’t change memory allocators (use defaults).
PYMEM_ALLOCATOR_DEFAULT ( 1 ): 默认内存分配器 .
PYMEM_ALLOCATOR_DEBUG ( 2 ): 默认内存分配器 with debug hooks .
PYMEM_ALLOCATOR_MALLOC ( 3 ): use malloc() of the C library.
PYMEM_ALLOCATOR_MALLOC_DEBUG ( 4 ): force usage of malloc() with debug hooks .
PYMEM_ALLOCATOR_PYMALLOC ( 5 ): Python pymalloc memory allocator .
PYMEM_ALLOCATOR_PYMALLOC_DEBUG ( 6 ): Python pymalloc memory allocator with debug hooks .
PYMEM_ALLOCATOR_MIMALLOC ( 6 ): use mimalloc , a fast malloc replacement.
PYMEM_ALLOCATOR_MIMALLOC_DEBUG ( 7 ): use mimalloc , a fast malloc replacement with debug hooks .

PYMEM_ALLOCATOR_PYMALLOC and PYMEM_ALLOCATOR_PYMALLOC_DEBUG are not supported if Python is configured using --without-pymalloc .

PYMEM_ALLOCATOR_MIMALLOC and PYMEM_ALLOCATOR_MIMALLOC_DEBUG are not supported if Python is configured using --without-mimalloc or if the underlying atomic support isn’t available.

见内存管理 .

默认： PYMEM_ALLOCATOR_NOT_SET .

int configure_locale ¶

Set the LC_CTYPE locale to the user preferred locale.

If equals to 0 , set coerce_c_locale and coerce_c_locale_warn members to 0 .

见区域设置编码 .

默认： 1 in Python config, 0 in isolated config.

int coerce_c_locale ¶

If equals to 2 , coerce the C locale.

If equals to 1 , read the LC_CTYPE locale to decide if it should be coerced.

见区域设置编码 .

默认： -1 in Python config, 0 in isolated config.

int coerce_c_locale_warn ¶

If non-zero, emit a warning if the C locale is coerced.

默认： -1 in Python config, 0 in isolated config.

int dev_mode ¶

Python 开发模式 : see PyConfig.dev_mode .

默认： -1 按 Python 模式， 0 按隔离模式。

int isolated ¶

Isolated mode: see PyConfig.isolated .

默认： 0 按 Python 模式， 1 按隔离模式。

int legacy_windows_fs_encoding ¶

If non-zero:

Set PyPreConfig.utf8_mode to 0 ,
Set PyConfig.filesystem_encoding to "mbcs" ,
Set PyConfig.filesystem_errors to "replace" .

Initialized from the PYTHONLEGACYWINDOWSFSENCODING environment variable value.

只可用于 Windows。 #ifdef MS_WINDOWS macro can be used for Windows specific code.

默认： 0 .

int parse_argv ¶

If non-zero, Py_PreInitializeFromArgs() and Py_PreInitializeFromBytesArgs() parse their argv argument the same way the regular Python parses command line arguments: see 命令行自变量 .

默认： 1 in Python config, 0 in isolated config.

int use_environment ¶

使用环境变量 ? See PyConfig.use_environment .

默认： 1 in Python config and 0 in isolated config.

int utf8_mode ¶

若非 0，启用 Python UTF-8 模式 .

设为 0 or 1 通过 -X utf8 命令行选项和 PYTHONUTF8 环境变量。

Also set to 1 若 LC_CTYPE 区域设置是 C or POSIX .

默认： -1 in Python config and 0 in isolated config.

采用 PyPreConfig 预初始化 Python ¶

Python 的预初始化：

Set the Python memory allocators ( PyPreConfig.allocator )
Configure the LC_CTYPE locale ( 区域设置编码 )
设置 Python UTF-8 模式 ( PyPreConfig.utf8_mode )

The current preconfiguration ( PyPreConfig type) is stored in _PyRuntime.preconfig .

Functions to preinitialize Python:

PyStatus Py_PreInitialize ( const PyPreConfig * preconfig ) ¶

Preinitialize Python from preconfig preconfiguration.

preconfig 不得为 NULL .

PyStatus Py_PreInitializeFromBytesArgs ( const PyPreConfig * preconfig , int argc , char * const * argv ) ¶

Preinitialize Python from preconfig preconfiguration.

剖析 argv command line arguments (bytes strings) if parse_argv of preconfig is non-zero.

preconfig 不得为 NULL .

PyStatus Py_PreInitializeFromArgs ( const PyPreConfig * preconfig , int argc , wchar_t * const * argv ) ¶

Preinitialize Python from preconfig preconfiguration.

剖析 argv command line arguments (wide strings) if parse_argv of preconfig is non-zero.

preconfig 不得为 NULL .

调用者负责处理异常 (错误或退出) 使用 PyStatus_Exception() and Py_ExitStatusException() .

For Python 配置 ( PyPreConfig_InitPythonConfig() ), if Python is initialized with command line arguments, the command line arguments must also be passed to preinitialize Python, since they have an effect on the pre-configuration like encodings. For example, the -X utf8 command line option enables the Python UTF-8 模式 .

PyMem_SetAllocator() can be called after Py_PreInitialize() and before Py_InitializeFromConfig() to install a custom memory allocator. It can be called before Py_PreInitialize() if PyPreConfig.allocator 被设为 PYMEM_ALLOCATOR_NOT_SET .

Python memory allocation functions like PyMem_RawMalloc() must not be used before the Python preinitialization, whereas calling directly malloc() and free() is always safe. Py_DecodeLocale() must not be called before the Python preinitialization.

Example using the preinitialization to enable the Python UTF-8 模式 :

PyStatus status;
PyPreConfig preconfig;
PyPreConfig_InitPythonConfig(&preconfig);
preconfig.utf8_mode = 1;
status = Py_PreInitialize(&preconfig);
if (PyStatus_Exception(status)) {
    Py_ExitStatusException(status);
}
/* at this point, Python speaks UTF-8 */
Py_Initialize();
/* ... use Python API here ... */
Py_Finalize();

PyConfig ¶

type PyConfig ¶

Structure containing most parameters to configure Python.

When done, the PyConfig_Clear() function must be used to release the configuration memory.

Structure 方法：

void PyConfig_InitPythonConfig ( PyConfig * config ) ¶: Initialize configuration with the Python 配置 .

void PyConfig_InitIsolatedConfig ( PyConfig * config ) ¶: Initialize configuration with the 隔离配置 .

PyStatus PyConfig_SetString ( PyConfig * config , wchar_t * const * config_str , const wchar_t * str ) ¶

Copy the wide character string str into *config_str .

预初始化 Python 若需要。

PyStatus PyConfig_SetBytesString ( PyConfig * config , wchar_t * const * config_str , const char * str ) ¶

解码 str 使用 Py_DecodeLocale() and set the result into *config_str .

预初始化 Python 若需要。

PyStatus PyConfig_SetArgv ( PyConfig * config , int argc , wchar_t * const * argv ) ¶

设置命令行自变量 ( argv member of config ) from the argv list of wide character strings.

预初始化 Python 若需要。

PyStatus PyConfig_SetBytesArgv ( PyConfig * config , int argc , char * const * argv ) ¶

设置命令行自变量 ( argv member of config ) from the argv list of bytes strings. Decode bytes using Py_DecodeLocale() .

预初始化 Python 若需要。

PyStatus PyConfig_SetWideStringList ( PyConfig * config , PyWideStringList * list , Py_ssize_t length , wchar_t * * items ) ¶

设置宽字符串列表 list to length and 项 .

预初始化 Python 若需要。

PyStatus PyConfig_Read ( PyConfig * config ) ¶

读取所有 Python 配置。

Fields which are already initialized are left unchanged.

Fields for 路径配置 are no longer calculated or modified when calling this function, as of Python 3.11.

The PyConfig_Read() function only parses PyConfig.argv arguments once: PyConfig.parse_argv 被设为 2 after arguments are parsed. Since Python arguments are stripped from PyConfig.argv , parsing arguments twice would parse the application options as Python options.

预初始化 Python 若需要。

3.10 版改变： The PyConfig.argv arguments are now only parsed once, PyConfig.parse_argv 被设为 2 after arguments are parsed, and arguments are only parsed if PyConfig.parse_argv 等于 1 .

3.11 版改变： PyConfig_Read() no longer calculates all paths, and so fields listed under Python 路径配置 may no longer be updated until Py_InitializeFromConfig() 被调用。

void PyConfig_Clear ( PyConfig * config ) ¶: Release configuration memory.

Most PyConfig 方法 preinitialize Python if needed. In that case, the Python preinitialization configuration ( PyPreConfig ) in based on the PyConfig . If configuration fields which are in common with PyPreConfig are tuned, they must be set before calling a PyConfig 方法：

PyConfig.dev_mode
PyConfig.isolated
PyConfig.parse_argv
PyConfig.use_environment

Moreover, if PyConfig_SetArgv() or PyConfig_SetBytesArgv() is used, this method must be called before other methods, since the preinitialization configuration depends on command line arguments (if parse_argv is non-zero).

The caller of these methods is responsible to handle exceptions (error or exit) using PyStatus_Exception() and Py_ExitStatusException() .

Structure fields:

PyWideStringList argv ¶

Set sys.argv command line arguments based on argv . These parameters are similar to those passed to the program’s main() function with the difference that the first entry should refer to the script file to be executed rather than the executable hosting the Python interpreter. If there isn’t a script that will be run, the first entry in argv can be an empty string.

Set parse_argv to 1 to parse argv the same way the regular Python parses Python command line arguments and then to strip Python arguments from argv .

若 argv is empty, an empty string is added to ensure that sys.argv always exists and is never empty.

默认： NULL .

另请参阅 orig_argv 成员。

int safe_path ¶

If equals to zero, Py_RunMain() prepends a potentially unsafe path to sys.path at startup:

若 argv[0] 等于 L"-m" ( python -m module ), prepend the current working directory.
If running a script ( python script.py ), prepend the script’s directory. If it’s a symbolic link, resolve symbolic links.
Otherwise ( python -c code and python ), prepend an empty string, which means the current working directory.

设为 1 通过 -P 命令行选项和 PYTHONSAFEPATH 环境变量。

默认： 0 in Python config, 1 in isolated config.

Added in version 3.11.

wchar_t * base_exec_prefix ¶

sys.base_exec_prefix .

默认： NULL .

属于 Python 路径配置输出。

另请参阅 PyConfig.exec_prefix .

wchar_t * base_executable ¶

Python base executable: sys._base_executable .

设置通过 __PYVENV_LAUNCHER__ 环境变量。

Set from PyConfig.executable if NULL .

默认： NULL .

属于 Python 路径配置输出。

另请参阅 PyConfig.executable .

wchar_t * base_prefix ¶

sys.base_prefix .

默认： NULL .

属于 Python 路径配置输出。

另请参阅 PyConfig.prefix .

int buffered_stdio ¶

If equals to 0 and configure_c_stdio is non-zero, disable buffering on the C streams stdout and stderr.

设为 0 通过 -u 命令行选项和 PYTHONUNBUFFERED 环境变量。

stdin is always opened in buffered mode.

默认： 1 .

int bytes_warning ¶

If equals to 1 , issue a warning when comparing bytes or bytearray with str , or comparing bytes with int .

If equal or greater to 2 ，引发 BytesWarning exception in these cases.

Incremented by the -b 命令行选项。

默认： 0 .

int warn_default_encoding ¶

If non-zero, emit a EncodingWarning warning when io.TextIOWrapper uses its default encoding. See 选择加入 EncodingWarning 了解细节。

默认： 0 .

3.10 版添加。

int code_debug_ranges ¶

If equals to 0 , disables the inclusion of the end line and column mappings in code objects. Also disables traceback printing carets to specific error locations.

设为 0 通过 PYTHONNODEBUGRANGES environment variable and by the -X no_debug_ranges 命令行选项。

默认： 1 .

Added in version 3.11.

wchar_t * check_hash_pycs_mode ¶

Control the validation behavior of hash-based .pyc files: value of the --check-hash-based-pycs 命令行选项。

Valid values:

L"always" : Hash the source file for invalidation regardless of value of the ‘check_source’ flag.
L"never" : Assume that hash-based pycs always are valid.
L"default" : The ‘check_source’ flag in hash-based pycs determines invalidation.

默认： L"default" .

另请参阅 PEP 552 “Deterministic pycs”.

int configure_c_stdio ¶

If non-zero, configure C standard streams:

On Windows, set the binary mode ( O_BINARY ) on stdin, stdout and stderr.
若 buffered_stdio equals zero, disable buffering of stdin, stdout and stderr streams.
若 interactive is non-zero, enable stream buffering on stdin and stdout (only stdout on Windows).

默认： 1 in Python config, 0 in isolated config.

int dev_mode ¶

若非 0，启用 Python 开发模式 .

设为 1 通过 -X dev 选项和 PYTHONDEVMODE 环境变量。

默认： -1 按 Python 模式， 0 按隔离模式。

int dump_refs ¶

转储 Python 引用？

If non-zero, dump all objects which are still alive at exit.

设为 1 通过 PYTHONDUMPREFS 环境变量。

Needs a special build of Python with the Py_TRACE_REFS macro defined: see the configure --with-trace-refs option .

默认： 0 .

wchar_t * exec_prefix ¶

The site-specific directory prefix where the platform-dependent Python files are installed: sys.exec_prefix .

默认： NULL .

属于 Python 路径配置输出。

另请参阅 PyConfig.base_exec_prefix .

wchar_t * executable ¶

The absolute path of the executable binary for the Python interpreter: sys.executable .

默认： NULL .

属于 Python 路径配置输出。

另请参阅 PyConfig.base_executable .

int faulthandler ¶

Enable faulthandler?

If non-zero, call faulthandler.enable() at startup.

设为 1 by -X faulthandler 和 PYTHONFAULTHANDLER 环境变量。

默认： -1 按 Python 模式， 0 按隔离模式。

wchar_t * filesystem_encoding ¶

Filesystem encoding : sys.getfilesystemencoding() .

On macOS, Android and VxWorks: use "utf-8" 在默认情况下。

在 Windows：使用 "utf-8" by default, or "mbcs" if legacy_windows_fs_encoding of PyPreConfig is non-zero.

Default encoding on other platforms:

"utf-8" if PyPreConfig.utf8_mode is non-zero.
"ascii" if Python detects that nl_langinfo(CODESET) announces the ASCII encoding, whereas the mbstowcs() function decodes from a different encoding (usually Latin1).
"utf-8" if nl_langinfo(CODESET) returns an empty string.
Otherwise, use the 区域设置编码 : nl_langinfo(CODESET) 结果。

At Python startup, the encoding name is normalized to the Python codec name. For example, "ANSI_X3.4-1968" 被替换采用 "ascii" .

另请参阅 filesystem_errors 成员。

wchar_t * filesystem_errors ¶

Filesystem error handler : sys.getfilesystemencodeerrors() .

在 Windows：使用 "surrogatepass" by default, or "replace" if legacy_windows_fs_encoding of PyPreConfig is non-zero.

在其它平台：使用 "surrogateescape" 在默认情况下。

支持的错误处理程序：

"strict"
"surrogateescape"
"surrogatepass" (only supported with the UTF-8 encoding)

另请参阅 filesystem_encoding 成员。

unsigned long hash_seed ¶

int use_hash_seed ¶

Randomized hash function seed.

若 use_hash_seed is zero, a seed is chosen randomly at Python startup, and hash_seed 被忽略。

设置通过 PYTHONHASHSEED 环境变量。

默认 use_hash_seed 值： -1 按 Python 模式， 0 按隔离模式。

wchar_t * home ¶

Set the default Python “home” directory, that is, the location of the standard Python libraries (see PYTHONHOME ).

设置通过 PYTHONHOME 环境变量。

默认： NULL .

属于 Python 路径配置输入。

int import_time ¶

If non-zero, profile import time.

设置 1 通过 -X importtime 选项和 PYTHONPROFILEIMPORTTIME 环境变量。

默认： 0 .

int inspect ¶

Enter interactive mode after executing a script or a command.

若大于 0 , enable inspect: when a script is passed as first argument or the -c option is used, enter interactive mode after executing the script or the command, even when sys.stdin does not appear to be a terminal.

Incremented by the -i command line option. Set to 1 若 PYTHONINSPECT environment variable is non-empty.

默认： 0 .

int install_signal_handlers ¶

安装 Python 信号处理程序？

默认： 1 按 Python 模式， 0 按隔离模式。

int interactive ¶

若大于 0 , enable the interactive mode (REPL).

Incremented by the -i 命令行选项。

默认： 0 .

int int_max_str_digits ¶

Configures the 整数字符串转换长度局限性 . An initial value of -1 means the value will be taken from the command line or environment or otherwise default to 4300 ( sys.int_info.default_max_str_digits ). A value of 0 disables the limitation. Values greater than zero but less than 640 ( sys.int_info.str_digits_check_threshold ) are unsupported and will produce an error.

Configured by the -X int_max_str_digits command line flag or the PYTHONINTMAXSTRDIGITS 环境变量。

默认： -1 in Python mode. 4300 ( sys.int_info.default_max_str_digits ) in isolated mode.

3.12 版添加。

int cpu_count ¶

若值 cpu_count 不是 -1 then it will override the return values of os.cpu_count() , os.process_cpu_count() ，和 multiprocessing.cpu_count() .

Configured by the -X cpu_count=n|default command line flag or the PYTHON_CPU_COUNT 环境变量。

默认： -1 .

3.13 版添加。

int isolated ¶

若大于 0 , enable isolated mode:

Set safe_path to 1 : don’t prepend a potentially unsafe path to sys.path at Python startup, such as the current directory, the script’s directory or an empty string.
Set use_environment to 0 : ignore PYTHON 环境变量。
Set user_site_directory to 0 : don’t add the user site directory to sys.path .
Python REPL doesn’t import readline nor enable default readline configuration on interactive prompts.

设为 1 通过 -I 命令行选项。

默认： 0 按 Python 模式， 1 按隔离模式。

另请参阅隔离配置 and PyPreConfig.isolated .

int legacy_windows_stdio ¶

If non-zero, use io.FileIO 而不是 io._WindowsConsoleIO for sys.stdin , sys.stdout and sys.stderr .

设为 1 若 PYTHONLEGACYWINDOWSSTDIO 环境变量被设为非空字符串。

只可用于 Windows。 #ifdef MS_WINDOWS macro can be used for Windows specific code.

默认： 0 .

另请参阅 PEP 528 (Change Windows console encoding to UTF-8).

int malloc_stats ¶

If non-zero, dump statistics on Python pymalloc memory allocator at exit.

设为 1 通过 PYTHONMALLOCSTATS 环境变量。

The option is ignored if Python is configured using the --without-pymalloc option .

默认： 0 .

wchar_t * platlibdir ¶

平台库目录名： sys.platlibdir .

设置通过 PYTHONPLATLIBDIR 环境变量。

Default: value of the PLATLIBDIR macro which is set by the configure --with-platlibdir option (default: "lib" ，或 "DLLs" 在 Windows)。

属于 Python 路径配置输入。

Added in version 3.9.

3.11 版改变： This macro is now used on Windows to locate the standard library extension modules, typically under DLLs . However, for compatibility, note that this value is ignored for any non-standard layouts, including in-tree builds and virtual environments.

wchar_t * pythonpath_env ¶

模块搜索路径 ( sys.path ) as a string separated by DELIM ( os.pathsep ).

设置通过 PYTHONPATH 环境变量。

默认： NULL .

属于 Python 路径配置输入。

PyWideStringList module_search_paths ¶

int module_search_paths_set ¶

模块搜索路径： sys.path .

若 module_search_paths_set 等于 0 , Py_InitializeFromConfig() will replace module_search_paths 并设置 module_search_paths_set to 1 .

Default: empty list ( module_search_paths ) 和 0 ( module_search_paths_set ).

属于 Python 路径配置输出。

int optimization_level ¶

编译优化级别：

0 : Peephole optimizer, set __debug__ to True .
1 : Level 0, remove assertions, set __debug__ to False .
2 : Level 1, strip docstrings.

Incremented by the -O command line option. Set to the PYTHONOPTIMIZE environment variable value.

默认： 0 .

PyWideStringList orig_argv ¶

The list of the original command line arguments passed to the Python executable: sys.orig_argv .

若 orig_argv list is empty and argv is not a list only containing an empty string, PyConfig_Read() copies argv into orig_argv before modifying argv (若 parse_argv is non-zero).

另请参阅 argv member and the Py_GetArgcArgv() 函数。

默认：空列表。

3.10 版添加。

int parse_argv ¶

Parse command line arguments?

If equals to 1 , parse argv the same way the regular Python parses command line arguments , and strip Python arguments from argv .

默认： 1 按 Python 模式， 0 按隔离模式。

3.10 版改变： The PyConfig.argv arguments are now only parsed if PyConfig.parse_argv equals to 1 .

int parser_debug ¶

Parser debug mode. If greater than 0 , turn on parser debugging output (for expert only, depending on compilation options).

Incremented by the -d command line option. Set to the PYTHONDEBUG environment variable value.

Needs a debug build of Python ( Py_DEBUG macro must be defined).

默认： 0 .

int pathconfig_warnings ¶

If non-zero, calculation of path configuration is allowed to log warnings into stderr . If equals to 0 , suppress these warnings.

默认： 1 按 Python 模式， 0 按隔离模式。

属于 Python 路径配置输入。

3.11 版改变： Now also applies on Windows.

wchar_t * prefix ¶

The site-specific directory prefix where the platform independent Python files are installed: sys.prefix .

默认： NULL .

属于 Python 路径配置输出。

另请参阅 PyConfig.base_prefix .

wchar_t * program_name ¶

Program name used to initialize executable and in early error messages during Python initialization.

On macOS, use PYTHONEXECUTABLE environment variable if set.
若 WITH_NEXT_FRAMEWORK macro is defined, use __PYVENV_LAUNCHER__ environment variable if set.
使用 argv[0] of argv if available and non-empty.
Otherwise, use L"python" on Windows, or L"python3" 在其它平台。

默认： NULL .

属于 Python 路径配置输入。

wchar_t * pycache_prefix ¶

Directory where cached .pyc files are written: sys.pycache_prefix .

设置通过 -X pycache_prefix=PATH 命令行选项和 PYTHONPYCACHEPREFIX environment variable. The command-line option takes precedence.

若 NULL , sys.pycache_prefix 被设为 None .

默认： NULL .

int quiet ¶

Quiet mode. If greater than 0 , don’t display the copyright and version at Python startup in interactive mode.

Incremented by the -q 命令行选项。

默认： 0 .

wchar_t * run_command ¶

Value of the -c 命令行选项。

用于 Py_RunMain() .

默认： NULL .

wchar_t * run_filename ¶

Filename passed on the command line: trailing command line argument without -c or -m . It is used by the Py_RunMain() 函数。

For example, it is set to script.py 通过 python3 script.py arg 命令行。

另请参阅 PyConfig.skip_source_first_line 选项。

默认： NULL .

wchar_t * run_module ¶

Value of the -m 命令行选项。

用于 Py_RunMain() .

默认： NULL .

wchar_t * run_presite ¶

package.module path to module that should be imported before site.py is run.

设置通过 -X presite=package.module command-line option and the PYTHON_PRESITE environment variable. The command-line option takes precedence.

Needs a debug build of Python ( Py_DEBUG macro must be defined).

默认： NULL .

int show_ref_count ¶

Show total reference count at exit (excluding immortal objects)?

设为 1 by -X showrefcount 命令行选项。

Needs a debug build of Python ( Py_REF_DEBUG macro must be defined).

默认： 0 .

int site_import ¶

导入 site module at startup?

If equal to zero, disable the import of the module site and the site-dependent manipulations of sys.path that it entails.

Also disable these manipulations if the site module is explicitly imported later (call site.main() 若想要触发它们)。

设为 0 通过 -S 命令行选项。

sys.flags.no_site is set to the inverted value of site_import .

默认： 1 .

int skip_source_first_line ¶

If non-zero, skip the first line of the PyConfig.run_filename 源。

It allows the usage of non-Unix forms of #!cmd . This is intended for a DOS specific hack only.

设为 1 通过 -x 命令行选项。

默认： 0 .

wchar_t * stdio_encoding ¶

wchar_t * stdio_errors ¶

Encoding and encoding errors of sys.stdin , sys.stdout and sys.stderr (但 sys.stderr always uses "backslashreplace" error handler).

使用 PYTHONIOENCODING environment variable if it is non-empty.

Default encoding:

"UTF-8" if PyPreConfig.utf8_mode is non-zero.
Otherwise, use the 区域设置编码 .

Default error handler:

在 Windows：使用 "surrogateescape" .
"surrogateescape" if PyPreConfig.utf8_mode is non-zero, or if the LC_CTYPE locale is “C” or “POSIX”.
"strict" 否则。

另请参阅 PyConfig.legacy_windows_stdio .

int tracemalloc ¶

Enable tracemalloc?

If non-zero, call tracemalloc.start() at startup.

设置通过 -X tracemalloc=N command line option and by the PYTHONTRACEMALLOC 环境变量。

默认： -1 按 Python 模式， 0 按隔离模式。

int perf_profiling ¶

Enable compatibility mode with the perf profiler?

If non-zero, initialize the perf trampoline. See Python support for the Linux perf profiler 了解更多信息。

设置通过 -X perf command-line option and by the PYTHON_PERF_JIT_SUPPORT environment variable for perf support with stack pointers and -X perf_jit command-line option and by the PYTHON_PERF_JIT_SUPPORT environment variable for perf support with DWARF JIT information.

默认： -1 .

3.12 版添加。

int use_environment ¶

使用环境变量 ?

If equals to zero, ignore the 环境变量 .

设为 0 通过 -E 环境变量。

默认： 1 in Python config and 0 in isolated config.

int user_site_directory ¶

If non-zero, add the user site directory to sys.path .

设为 0 通过 -s and -I command line options.

设为 0 通过 PYTHONNOUSERSITE 环境变量。

默认： 1 按 Python 模式， 0 按隔离模式。

int verbose ¶

Verbose mode. If greater than 0 , print a message each time a module is imported, showing the place (filename or built-in module) from which it is loaded.

If greater than or equal to 2 , print a message for each file that is checked for when searching for a module. Also provides information on module cleanup at exit.

Incremented by the -v 命令行选项。

设置通过 PYTHONVERBOSE environment variable value.

默认： 0 .

PyWideStringList warnoptions ¶

Options of the warnings module to build warnings filters, lowest to highest priority: sys.warnoptions .

The warnings module adds sys.warnoptions in the reverse order: the last PyConfig.warnoptions item becomes the first item of warnings.filters which is checked first (highest priority).

The -W command line options adds its value to warnoptions , it can be used multiple times.

The PYTHONWARNINGS environment variable can also be used to add warning options. Multiple options can be specified, separated by commas ( , ).

默认：空列表。

int write_bytecode ¶

若等于 0 ，Python 不会试着写入 .pyc files on the import of source modules.

设为 0 通过 -B 命令行选项和 PYTHONDONTWRITEBYTECODE 环境变量。

sys.dont_write_bytecode is initialized to the inverted value of write_bytecode .

默认： 1 .

PyWideStringList xoptions ¶

Values of the -X 命令行选项： sys._xoptions .

默认：空列表。

若 parse_argv 非 0， argv arguments are parsed the same way the regular Python parses command line arguments , and Python arguments are stripped from argv .

The xoptions options are parsed to set other options: see the -X 命令行选项。

3.9 版改变： The show_alloc_count 字段被移除。

采用 PyConfig 初始化 ¶

Initializing the interpreter from a populated configuration struct is handled by calling Py_InitializeFromConfig() .

调用者负责处理异常 (错误或退出) 使用 PyStatus_Exception() and Py_ExitStatusException() .

若 PyImport_FrozenModules() , PyImport_AppendInittab() or PyImport_ExtendInittab() are used, they must be set or called after Python preinitialization and before the Python initialization. If Python is initialized multiple times, PyImport_AppendInittab() or PyImport_ExtendInittab() must be called before each Python initialization.

当前配置 ( PyConfig type) is stored in PyInterpreterState.config .

范例设置程序名称：

void init_python(void)
{
    PyStatus status;
    PyConfig config;
    PyConfig_InitPythonConfig(&config);
    /* Set the program name. Implicitly preinitialize Python. */
    status = PyConfig_SetString(&config, &config.program_name,
                                L"/path/to/my_program");
    if (PyStatus_Exception(status)) {
        goto exception;
    }
    status = Py_InitializeFromConfig(&config);
    if (PyStatus_Exception(status)) {
        goto exception;
    }
    PyConfig_Clear(&config);
    return;
exception:
    PyConfig_Clear(&config);
    Py_ExitStatusException(status);
}

More complete example modifying the default configuration, read the configuration, and then override some parameters. Note that since 3.11, many parameters are not calculated until initialization, and so values cannot be read from the configuration structure. Any values set before initialize is called will be left unchanged by initialization:

PyStatus init_python(const char *program_name)
{
    PyStatus status;
    PyConfig config;
    PyConfig_InitPythonConfig(&config);
    /* Set the program name before reading the configuration
       (decode byte string from the locale encoding).
       Implicitly preinitialize Python. */
    status = PyConfig_SetBytesString(&config, &config.program_name,
                                     program_name);
    if (PyStatus_Exception(status)) {
        goto done;
    }
    /* Read all configuration at once */
    status = PyConfig_Read(&config);
    if (PyStatus_Exception(status)) {
        goto done;
    }
    /* Specify sys.path explicitly */
    /* If you want to modify the default set of paths, finish
       initialization first and then use PySys_GetObject("path") */
    config.module_search_paths_set = 1;
    status = PyWideStringList_Append(&config.module_search_paths,
                                     L"/path/to/stdlib");
    if (PyStatus_Exception(status)) {
        goto done;
    }
    status = PyWideStringList_Append(&config.module_search_paths,
                                     L"/path/to/more/modules");
    if (PyStatus_Exception(status)) {
        goto done;
    }
    /* Override executable computed by PyConfig_Read() */
    status = PyConfig_SetString(&config, &config.executable,
                                L"/path/to/my_executable");
    if (PyStatus_Exception(status)) {
        goto done;
    }
    status = Py_InitializeFromConfig(&config);
done:
    PyConfig_Clear(&config);
    return status;
}

隔离配置 ¶

PyPreConfig_InitIsolatedConfig() and PyConfig_InitIsolatedConfig() functions create a configuration to isolate Python from the system. For example, to embed Python into an application.

This configuration ignores global configuration variables, environment variables, command line arguments ( PyConfig.argv is not parsed) and user site directory. The C standard streams (ex: stdout ) and the LC_CTYPE locale are left unchanged. Signal handlers are not installed.

Configuration files are still used with this configuration to determine paths that are unspecified. Ensure PyConfig.home is specified to avoid computing the default path configuration.

Python 配置 ¶

PyPreConfig_InitPythonConfig() and PyConfig_InitPythonConfig() functions create a configuration to build a customized Python which behaves as the regular Python.

Environments variables and command line arguments are used to configure Python, whereas global configuration variables are ignored.

此函数启用 C 区域设置强制 ( PEP 538 ) 和 Python UTF-8 模式 ( PEP 540 ) 从属 LC_CTYPE 区域设置， PYTHONUTF8 and PYTHONCOERCECLOCALE 环境变量。

Python 路径配置 ¶

PyConfig 包含路径配置的多个字段：

路径配置输入：
- PyConfig.home
- PyConfig.platlibdir
- PyConfig.pathconfig_warnings
- PyConfig.program_name
- PyConfig.pythonpath_env
- current working directory: to get absolute paths
- PATH environment variable to get the program full path (from PyConfig.program_name )
- __PYVENV_LAUNCHER__ 环境变量
- (Windows only) Application paths in the registry under “SoftwarePythonPythonCoreX.YPythonPath” of HKEY_CURRENT_USER and HKEY_LOCAL_MACHINE (where X.Y is the Python version).
路径配置输出字段：

If at least one “output field” is not set, Python calculates the path configuration to fill unset fields. If module_search_paths_set 等于 0 , module_search_paths is overridden and module_search_paths_set 被设为 1 .

It is possible to completely ignore the function calculating the default path configuration by setting explicitly all path configuration output fields listed above. A string is considered as set even if it is non-empty. module_search_paths is considered as set if module_search_paths_set 被设为 1 。在此情况下， module_search_paths will be used without modification.

Set pathconfig_warnings to 0 to suppress warnings when calculating the path configuration (Unix only, Windows does not log any warning).

若 base_prefix or base_exec_prefix fields are not set, they inherit their value from prefix and exec_prefix 分别。

Py_RunMain() and Py_Main() 修改 sys.path :

若 run_filename is set and is a directory which contains a __main__.py script, prepend run_filename to sys.path .
若 isolated 为 0：
- 若 run_module is set, prepend the current directory to sys.path . Do nothing if the current directory cannot be read.
- 若 run_filename is set, prepend the directory of the filename to sys.path .
- Otherwise, prepend an empty string to sys.path .

若 site_import 非 0， sys.path can be modified by the site module. If user_site_directory is non-zero and the user’s site-package directory exists, the site module appends the user’s site-package directory to sys.path .

The following configuration files are used by the path configuration:

pyvenv.cfg
._pth file (ex: python._pth )
pybuilddir.txt (仅 Unix)

若 ._pth 文件存在：

Set isolated to 1 .
Set use_environment to 0 .
Set site_import to 0 .
Set safe_path to 1 .

The __PYVENV_LAUNCHER__ 环境变量用于设置 PyConfig.base_executable .

Py_GetArgcArgv() ¶

void Py_GetArgcArgv ( int * argc , wchar_t * * * argv ) ¶

Get the original command line arguments, before Python modified them.

另请参阅 PyConfig.orig_argv 成员。

多阶段初始化私有暂行 API ¶

This section is a private provisional API introducing multi-phase initialization, the core feature of PEP 432 :

“Core” initialization phase, “bare minimum Python”:
- Builtin types;
- Builtin exceptions;
- Builtin and frozen modules;
- The sys module is only partially initialized (ex: sys.path doesn’t exist yet).
“Main” initialization phase, Python is fully initialized:
- Install and configure importlib ;
- Apply the 路径配置 ;
- Install signal handlers;
- Finish sys module initialization (ex: create sys.stdout and sys.path );
- Enable optional features like faulthandler and tracemalloc ;
- 导入 site 模块；
- etc.

Private provisional API:

PyConfig._init_main : if set to 0 , Py_InitializeFromConfig() stops at the “Core” initialization phase.

PyStatus _Py_InitializeMain ( void ) ¶: Move to the “Main” initialization phase, finish the Python initialization.

No module is imported during the “Core” phase and the importlib module is not configured: the 路径配置 is only applied during the “Main” phase. It may allow to customize Python in Python to override or tune the 路径配置 , maybe install a custom sys.meta_path importer or an import hook, etc.

It may become possible to calculate the 路径配置 in Python, after the Core phase and before the Main phase, which is one of the PEP 432 motivation.

The “Core” phase is not properly defined: what should be and what should not be available at this phase is not specified yet. The API is marked as private and provisional: the API can be modified or even be removed anytime until a proper public API is designed.

Example running Python code between “Core” and “Main” initialization phases:

void init_python(void)
{
    PyStatus status;
    PyConfig config;
    PyConfig_InitPythonConfig(&config);
    config._init_main = 0;
    /* ... customize 'config' configuration ... */
    status = Py_InitializeFromConfig(&config);
    PyConfig_Clear(&config);
    if (PyStatus_Exception(status)) {
        Py_ExitStatusException(status);
    }
    /* Use sys.stderr because sys.stdout is only created
       by _Py_InitializeMain() */
    int res = PyRun_SimpleString(
        "import sys; "
        "print('Run Python code before _Py_InitializeMain', "
               "file=sys.stderr)");
    if (res < 0) {
        exit(1);
    }
    /* ... put more configuration code here ... */
    status = _Py_InitializeMain();
    if (PyStatus_Exception(status)) {
        Py_ExitStatusException(status);
    }
}

内容表

上一话题

下一话题

本页

Python 初始化配置 ¶

范例 ¶

PyWideStringList ¶

PyStatus ¶

PyPreConfig ¶

采用 PyPreConfig 预初始化 Python ¶

PyConfig ¶

采用 PyConfig 初始化 ¶

隔离配置 ¶

Python 配置 ¶

Python 路径配置 ¶

Py_GetArgcArgv() ¶

多阶段初始化私有暂行 API ¶

内容表

上一话题

下一话题

本页