kopia lustrzana https://github.com/micropython/micropython
124 wiersze
3.7 KiB
ReStructuredText
124 wiersze
3.7 KiB
ReStructuredText
:mod:`sys` -- system specific functions
|
|
=======================================
|
|
|
|
.. module:: sys
|
|
:synopsis: system specific functions
|
|
|
|
|see_cpython_module| :mod:`python:sys`.
|
|
|
|
Functions
|
|
---------
|
|
|
|
.. function:: exit(retval=0)
|
|
|
|
Terminate current program with a given exit code. Underlyingly, this
|
|
function raise as `SystemExit` exception. If an argument is given, its
|
|
value given as an argument to `SystemExit`.
|
|
|
|
.. function:: print_exception(exc, file=sys.stdout)
|
|
|
|
Print exception with a traceback to a file-like object *file* (or
|
|
`sys.stdout` by default).
|
|
|
|
.. admonition:: Difference to CPython
|
|
:class: attention
|
|
|
|
This is simplified version of a function which appears in the
|
|
``traceback`` module in CPython. Unlike ``traceback.print_exception()``,
|
|
this function takes just exception value instead of exception type,
|
|
exception value, and traceback object; *file* argument should be
|
|
positional; further arguments are not supported. CPython-compatible
|
|
``traceback`` module can be found in `micropython-lib`.
|
|
|
|
Constants
|
|
---------
|
|
|
|
.. data:: argv
|
|
|
|
A mutable list of arguments the current program was started with.
|
|
|
|
.. data:: byteorder
|
|
|
|
The byte order of the system (``"little"`` or ``"big"``).
|
|
|
|
.. data:: implementation
|
|
|
|
Object with information about the current Python implementation. For
|
|
MicroPython, it has following attributes:
|
|
|
|
* *name* - string "micropython"
|
|
* *version* - tuple (major, minor, micro), e.g. (1, 7, 0)
|
|
|
|
This object is the recommended way to distinguish MicroPython from other
|
|
Python implementations (note that it still may not exist in the very
|
|
minimal ports).
|
|
|
|
.. admonition:: Difference to CPython
|
|
:class: attention
|
|
|
|
CPython mandates more attributes for this object, but the actual useful
|
|
bare minimum is implemented in MicroPython.
|
|
|
|
.. data:: maxsize
|
|
|
|
Maximum value which a native integer type can hold on the current platform,
|
|
or maximum value representable by MicroPython integer type, if it's smaller
|
|
than platform max value (that is the case for MicroPython ports without
|
|
long int support).
|
|
|
|
This attribute is useful for detecting "bitness" of a platform (32-bit vs
|
|
64-bit, etc.). It's recommended to not compare this attribute to some
|
|
value directly, but instead count number of bits in it::
|
|
|
|
bits = 0
|
|
v = sys.maxsize
|
|
while v:
|
|
bits += 1
|
|
v >>= 1
|
|
if bits > 32:
|
|
# 64-bit (or more) platform
|
|
...
|
|
else:
|
|
# 32-bit (or less) platform
|
|
# Note that on 32-bit platform, value of bits may be less than 32
|
|
# (e.g. 31) due to peculiarities described above, so use "> 16",
|
|
# "> 32", "> 64" style of comparisons.
|
|
|
|
.. data:: modules
|
|
|
|
Dictionary of loaded modules. On some ports, it may not include builtin
|
|
modules.
|
|
|
|
.. data:: path
|
|
|
|
A mutable list of directories to search for imported modules.
|
|
|
|
.. data:: platform
|
|
|
|
The platform that MicroPython is running on. For OS/RTOS ports, this is
|
|
usually an identifier of the OS, e.g. ``"linux"``. For baremetal ports it
|
|
is an identifier of a board, e.g. ``"pyboard"`` for the original MicroPython
|
|
reference board. It thus can be used to distinguish one board from another.
|
|
If you need to check whether your program runs on MicroPython (vs other
|
|
Python implementation), use `sys.implementation` instead.
|
|
|
|
.. data:: stderr
|
|
|
|
Standard error `stream`.
|
|
|
|
.. data:: stdin
|
|
|
|
Standard input `stream`.
|
|
|
|
.. data:: stdout
|
|
|
|
Standard output `stream`.
|
|
|
|
.. data:: version
|
|
|
|
Python language version that this implementation conforms to, as a string.
|
|
|
|
.. data:: version_info
|
|
|
|
Python language version that this implementation conforms to, as a tuple of ints.
|