* Add F_SETPIPE_SZ and F_GETPIPE_SZ to fcntl module
* Add pipesize parameter for subprocess.Popen class
This will allow the user to control the size of the pipes.
On linux the default is 64K. When a pipe is full it blocks for writing.
When a pipe is empty it blocks for reading. On processes that are
very fast this can lead to a lot of wasted CPU cycles. On a typical
Linux system the max pipe size is 1024K which is much better.
For high performance-oriented libraries such as xopen it is nice to
be able to set the pipe size.
The workaround without this feature is to use my_popen_process.stdout.fileno() in
conjuction with fcntl and 1031 (value of F_SETPIPE_SZ) to acquire this behavior.
Prepare unicodedata to add a state per module: start with a global
"module" state, pass it to subfunctions which access &UCD_Type. This
change also prepares the conversion of the UCD_Type static type to a
heap type.
This API is relatively lightweight and organizationally, given that it's
used by multiple modules, it makes sense to move it to fileutils.
Requires making sure that _posixsubprocess is compiled with the appropriate
Py_BUIILD_CORE_BUILTIN macro.
This suppression is no longer needed in os_closerange_impl, as it just
invokes the internal _Py_closerange implementation. On the other hand,
consumers of _Py_closerange may not have any other reason to suppress
invalid parameter issues, so narrow the scope to here.
close_range(2) should be preferred at all times if it's available, otherwise we'll use closefrom(2) if available with a fallback to fdwalk(3) or plain old loop over fd range in order of most efficient to least.
[note that this version does check for ENOSYS, but currently ignores all other errors]
Automerge-Triggered-By: @pablogsal
Such an API can be used both for os.closerange and subprocess. For the latter, this yields potential improvement for platforms that have fdwalk but wouldn't have used it there. This will prove even more beneficial later for platforms that have close_range(2), as the new API will prefer that over all else if it's available.
The new API is structured to look more like close_range(2), closing from [start, end] rather than the [low, high) of os.closerange().
Automerge-Triggered-By: @gpshead
* bpo-26680: Adds support for int.is_integer() for compatibility with float.is_integer().
The int.is_integer() method always returns True.
* bpo-26680: Adds a test to ensure that False.is_integer() and True.is_integer() are always True.
* bpo-26680: Adds Real.is_integer() with a trivial implementation using conversion to int.
This default implementation is intended to reduce the workload for subclass
implementers. It is not robust in the presence of infinities or NaNs and
may have suboptimal performance for other types.
* bpo-26680: Adds Rational.is_integer which returns True if the denominator is one.
This implementation assumes the Rational is represented in it's
lowest form, as required by the class docstring.
* bpo-26680: Adds Integral.is_integer which always returns True.
* bpo-26680: Adds tests for Fraction.is_integer called as an instance method.
The tests for the Rational abstract base class use an unbound
method to sidestep the inability to directly instantiate Rational.
These tests check that everything works correct as an instance method.
* bpo-26680: Updates documentation for Real.is_integer and built-ins int and float.
The call x.is_integer() is now listed in the table of operations
which apply to all numeric types except complex, with a reference
to the full documentation for Real.is_integer(). Mention of
is_integer() has been removed from the section 'Additional Methods
on Float'.
The documentation for Real.is_integer() describes its purpose, and
mentions that it should be overridden for performance reasons, or
to handle special values like NaN.
* bpo-26680: Adds Decimal.is_integer to the Python and C implementations.
The C implementation of Decimal already implements and uses
mpd_isinteger internally, we just expose the existing function to
Python.
The Python implementation uses internal conversion to integer
using to_integral_value().
In both cases, the corresponding context methods are also
implemented.
Tests and documentation are included.
* bpo-26680: Updates the ACKS file.
* bpo-26680: NEWS entries for int, the numeric ABCs and Decimal.
Co-authored-by: Robert Smallshire <rob@sixty-north.com>
Use _PyType_HasFeature() in the _io module and in structseq
implementation. Replace PyType_HasFeature() opaque function call with
_PyType_HasFeature() inlined function.
The new API allows to efficiently send values into native generators
and coroutines avoiding use of StopIteration exceptions to signal
returns.
ceval loop now uses this method instead of the old "private"
_PyGen_Send C API. This translates to 1.6x increased performance
of 'await' calls in micro-benchmarks.
Aside from CPython core improvements, this new API will also allow
Cython to generate more efficient code, benefiting high-performance
IO libraries like uvloop.
* When the parameters argument is a list, correctly handle the case
of changing it during iteration.
* When the parameters argument is a custom sequence, no longer
override an exception raised in ``__len__()``.
I just realized that my recent PR with sendfile on Solaris ([PR 22040](https://github.com/python/cpython/pull/22040)) has broken error handling.
Sorry for that, this simple followup fixes that.
Automerge-Triggered-By: @1st1
TIGirardi
Jakub Jelen
Raymond Hettinger
Ruben Vorderman
Jason R. Coombs
Serhiy Storchaka
Hai Shi
Victor Stinner
Erlend Egeberg Aasland
Brandt Bucher
Kyle Evans
Yunlongs
Vladimir Matveev
Ram Rachum
Robert Smallshire
Dong-hee Na
Zackery Spytz
Mohamed Koubaa
Thomas Grainger
Berker Peksag
Peter McCormick
Jakub Kulík