最終更新:2025-02-04 (火) 12:01:02 (97d)  

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  • usage: python3 [option] ... [-c cmd | -m mod | file | -] [arg] ...
    Options and arguments (and corresponding environment variables):
    -b     : issue warnings about str(bytes_instance), str(bytearray_instance)
             and comparing bytes/bytearray with str. (-bb: issue errors)
    -B     : don't write .pyc files on import; also PYTHONDONTWRITEBYTECODE=x
    -c cmd : program passed in as string (terminates option list)
    -d     : turn on parser debugging output (for experts only, only works on
             debug builds); also PYTHONDEBUG=x
    -E     : ignore PYTHON* environment variables (such as PYTHONPATH)
    -h     : print this help message and exit (also -? or --help)
    -i     : inspect interactively after running script; forces a prompt even
             if stdin does not appear to be a terminal; also PYTHONINSPECT=x
    -I     : isolate Python from the user's environment (implies -E and -s)
    -m mod : run library module as a script (terminates option list)
    -O     : remove assert and __debug__-dependent statements; add .opt-1 before
             .pyc extension; also PYTHONOPTIMIZE=x
    -OO    : do -O changes and also discard docstrings; add .opt-2 before
             .pyc extension
    -q     : don't print version and copyright messages on interactive startup
    -s     : don't add user site directory to sys.path; also PYTHONNOUSERSITE
    -S     : don't imply 'import site' on initialization
    -u     : force the stdout and stderr streams to be unbuffered;
             this option has no effect on stdin; also PYTHONUNBUFFERED=x
    -v     : verbose (trace import statements); also PYTHONVERBOSE=x
             can be supplied multiple times to increase verbosity
    -V     : print the Python version number and exit (also --version)
             when given twice, print more information about the build
    -W arg : warning control; arg is action:message:category:module:lineno
             also PYTHONWARNINGS=arg
    -x     : skip first line of source, allowing use of non-Unix forms of #!cmd
    -X opt : set implementation-specific option. The following options are available:
             -X faulthandler: enable faulthandler
             -X showrefcount: output the total reference count and number of used
                 memory blocks when the program finishes or after each statement in the
                 interactive interpreter. This only works on debug builds
             -X tracemalloc: start tracing Python memory allocations using the
                 tracemalloc module. By default, only the most recent frame is stored in a
                 traceback of a trace. Use -X tracemalloc=NFRAME to start tracing with a
                 traceback limit of NFRAME frames
             -X importtime: show how long each import takes. It shows module name,
                 cumulative time (including nested imports) and self time (excluding
                 nested imports). Note that its output may be broken in multi-threaded
                 application. Typical usage is python3 -X importtime -c 'import asyncio'
             -X dev: enable CPython's "development mode", introducing additional runtime
                 checks which are too expensive to be enabled by default. Effect of the
                 developer mode:
                    * Add default warning filter, as -W default
                    * Install debug hooks on memory allocators: see the PyMem_SetupDebugHooks()
                      C function
                    * Enable the faulthandler module to dump the Python traceback on a crash
                    * Enable asyncio debug mode
                    * Set the dev_mode attribute of sys.flags to True
                    * io.IOBase destructor logs close() exceptions
             -X utf8: enable UTF-8 mode for operating system interfaces, overriding the default
                 locale-aware mode. -X utf8=0 explicitly disables UTF-8 mode (even when it would
                 otherwise activate automatically)
             -X pycache_prefix=PATH: enable writing .pyc files to a parallel tree rooted at the
                 given directory instead of to the code tree
             -X warn_default_encoding: enable opt-in EncodingWarning for 'encoding=None'
             -X int_max_str_digits=number: limit the size of int<->str conversions.
                 This helps avoid denial of service attacks when parsing untrusted data.
                 The default is sys.int_info.default_max_str_digits.  0 disables.
    
    --check-hash-based-pycs always|default|never:
        control how Python invalidates hash-based .pyc files
    file   : program read from script file
    -      : program read from stdin (default; interactive mode if a tty)
    arg ...: arguments passed to program in sys.argv[1:]
    
    Other environment variables:
    PYTHONSTARTUP: file executed on interactive startup (no default)
    PYTHONPATH   : ':'-separated list of directories prefixed to the
                   default module search path.  The result is sys.path.
    PYTHONHOME   : alternate <prefix> directory (or <prefix>:<exec_prefix>).
                   The default module search path uses <prefix>/lib/pythonX.X.
    PYTHONPLATLIBDIR : override sys.platlibdir.
    PYTHONCASEOK : ignore case in 'import' statements (Windows).
    PYTHONUTF8: if set to 1, enable the UTF-8 mode.
    PYTHONIOENCODING: Encoding[:errors] used for stdin/stdout/stderr.
    PYTHONFAULTHANDLER: dump the Python traceback on fatal errors.
    PYTHONHASHSEED: if this variable is set to 'random', a random value is used
       to seed the hashes of str and bytes objects.  It can also be set to an
       integer in the range [0,4294967295] to get hash values with a
       predictable seed.
    PYTHONINTMAXSTRDIGITS: limits the maximum digit characters in an int value
       when converting from a string and when converting an int back to a str.
       A value of 0 disables the limit.  Conversions to or from bases 2, 4, 8,
       16, and 32 are never limited.
    PYTHONMALLOC: set the Python memory allocators and/or install debug hooks
       on Python memory allocators. Use PYTHONMALLOC=debug to install debug
       hooks.
    PYTHONCOERCECLOCALE: if this variable is set to 0, it disables the locale
       coercion behavior. Use PYTHONCOERCECLOCALE=warn to request display of
       locale coercion and locale compatibility warnings on stderr.
    PYTHONBREAKPOINT: if this variable is set to 0, it disables the default
       debugger. It can be set to the callable of your debugger of choice.
    PYTHONDEVMODE: enable the development mode.
    PYTHONPYCACHEPREFIX: root directory for bytecode cache (pyc) files.
    PYTHONWARNDEFAULTENCODING: enable opt-in EncodingWarning for 'encoding=None'.