最終更新:2025-02-04 (火) 12:01:02 (97d)
python3
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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'.
