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bpo-30404: The -u option now makes the stdout and stderr streams tota… · python/cpython@77732be

4 files changed

lines changed

Original file line numberDiff line numberDiff line change

@@ -303,13 +303,13 @@ Miscellaneous options

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.. cmdoption:: -u

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Force the binary layer of the stdout and stderr streams (which is

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available as their ``buffer`` attribute) to be unbuffered. The text I/O

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layer will still be line-buffered if writing to the console, or

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block-buffered if redirected to a non-interactive file.

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Force the stdout and stderr streams to be unbuffered.

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See also :envvar:`PYTHONUNBUFFERED`.

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.. versionchanged:: 3.7

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The text layer of the stdout and stderr streams now is unbuffered.

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.. cmdoption:: -v

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Original file line numberDiff line numberDiff line change

@@ -221,13 +221,12 @@ def test_unbuffered_output(self):

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rc, out, err = assert_python_ok('-u', '-c', code)

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data = err if stream == 'stderr' else out

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self.assertEqual(data, b'x', "binary %s not unbuffered" % stream)

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# Text is line-buffered

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code = ("import os, sys; sys.%s.write('x\\n'); os._exit(0)"

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# Text is unbuffered

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code = ("import os, sys; sys.%s.write('x'); os._exit(0)"

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% stream)

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rc, out, err = assert_python_ok('-u', '-c', code)

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data = err if stream == 'stderr' else out

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self.assertEqual(data.strip(), b'x',

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"text %s not line-buffered" % stream)

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self.assertEqual(data, b'x', "text %s not unbuffered" % stream)

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def test_unbuffered_input(self):

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# sys.stdin still works with '-u'

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@@ -0,0 +1,2 @@

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The -u option now makes the stdout and stderr streams unbuffered rather than

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line-buffered.

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@@ -1498,7 +1498,7 @@ create_stdio(PyObject* io,

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PyObject *buf = NULL, *stream = NULL, *text = NULL, *raw = NULL, *res;

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const char* mode;

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const char* newline;

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PyObject *line_buffering;

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PyObject *line_buffering, *write_through;

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int buffering, isatty;

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_Py_IDENTIFIER(open);

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_Py_IDENTIFIER(isatty);

@@ -1555,7 +1555,11 @@ create_stdio(PyObject* io,

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Py_DECREF(res);

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if (isatty == -1)

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goto error;

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if (isatty || Py_UnbufferedStdioFlag)

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if (Py_UnbufferedStdioFlag)

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write_through = Py_True;

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else

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write_through = Py_False;

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if (isatty && !Py_UnbufferedStdioFlag)

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line_buffering = Py_True;

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else

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line_buffering = Py_False;

@@ -1574,9 +1578,9 @@ create_stdio(PyObject* io,

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newline = "\n";

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#endif

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stream = _PyObject_CallMethodId(io, &PyId_TextIOWrapper, "OsssO",

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stream = _PyObject_CallMethodId(io, &PyId_TextIOWrapper, "OsssOO",

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buf, encoding, errors,

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newline, line_buffering);

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newline, line_buffering, write_through);

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Py_CLEAR(buf);

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if (stream == NULL)

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goto error;