diff --git a/Doc/library/tty.rst b/Doc/library/tty.rst index 20ba7d7e0a4..ed63561c40d 100644 --- a/Doc/library/tty.rst +++ b/Doc/library/tty.rst @@ -35,8 +35,15 @@ The :mod:`tty` module defines the following functions: Convert the tty attribute list *mode*, which is a list like the one returned by :func:`termios.tcgetattr`, to that of a tty in cbreak mode. + This clears the ``ECHO`` and ``ICANON`` local mode flags in *mode* as well + as setting the minimum input to 1 byte with no delay. + .. versionadded:: 3.12 + .. versionchanged:: 3.12.2 + The ``ICRNL`` flag is no longer cleared. This matches Linux and macOS + ``stty cbreak`` behavior and what :func:`setcbreak` historically did. + .. function:: setraw(fd, when=termios.TCSAFLUSH) @@ -56,9 +63,17 @@ The :mod:`tty` module defines the following functions: :func:`termios.tcsetattr`. The return value of :func:`termios.tcgetattr` is saved before setting *fd* to cbreak mode; this value is returned. + This clears the ``ECHO`` and ``ICANON`` local mode flags as well as setting + the minimum input to 1 byte with no delay. + .. versionchanged:: 3.12 The return value is now the original tty attributes, instead of None. + .. versionchanged:: 3.12.2 + The ``ICRNL`` flag is no longer cleared. This restores the behavior + of Python 3.11 and earlier as well as matching what Linux, macOS, & BSDs + describe in their ``stty(1)`` man pages regarding cbreak mode. + .. seealso:: diff --git a/Lib/test/test_tty.py b/Lib/test/test_tty.py index af20864aac3..4cb730c226f 100644 --- a/Lib/test/test_tty.py +++ b/Lib/test/test_tty.py @@ -19,7 +19,6 @@ class TestTty(unittest.TestCase): self.addCleanup(termios.tcsetattr, self.fd, termios.TCSAFLUSH, self.mode) def check_cbreak(self, mode): - self.assertEqual(mode[0] & termios.ICRNL, 0) self.assertEqual(mode[3] & termios.ECHO, 0) self.assertEqual(mode[3] & termios.ICANON, 0) self.assertEqual(mode[6][termios.VMIN], 1) @@ -56,6 +55,14 @@ class TestTty(unittest.TestCase): self.assertEqual(mode[2], self.mode[2]) self.assertEqual(mode[4], self.mode[4]) self.assertEqual(mode[5], self.mode[5]) + mode[tty.IFLAG] |= termios.ICRNL + tty.cfmakecbreak(mode) + self.assertEqual(mode[tty.IFLAG] & termios.ICRNL, termios.ICRNL, + msg="ICRNL should not be cleared by cbreak") + mode[tty.IFLAG] &= ~termios.ICRNL + tty.cfmakecbreak(mode) + self.assertEqual(mode[tty.IFLAG] & termios.ICRNL, 0, + msg="ICRNL should not be set by cbreak") def test_setraw(self): mode0 = termios.tcgetattr(self.fd) @@ -74,6 +81,9 @@ class TestTty(unittest.TestCase): self.assertEqual(mode1, mode0) mode2 = termios.tcgetattr(self.fd) self.check_cbreak(mode2) + ICRNL = termios.ICRNL + self.assertEqual(mode2[tty.IFLAG] & ICRNL, mode0[tty.IFLAG] & ICRNL, + msg="ICRNL should not be altered by cbreak") mode3 = tty.setcbreak(self.fd, termios.TCSANOW) self.assertEqual(mode3, mode2) tty.setcbreak(self.stream) diff --git a/Lib/tty.py b/Lib/tty.py index 283e5c334f5..5a49e040042 100644 --- a/Lib/tty.py +++ b/Lib/tty.py @@ -45,9 +45,6 @@ def cfmakeraw(mode): def cfmakecbreak(mode): """Make termios mode cbreak.""" - # Do not map CR to NL on input. - mode[IFLAG] &= ~(ICRNL) - # Do not echo characters; disable canonical input. mode[LFLAG] &= ~(ECHO | ICANON) diff --git a/Misc/NEWS.d/next/Library/2024-01-19-15-48-06.gh-issue-114328.hixxW3.rst b/Misc/NEWS.d/next/Library/2024-01-19-15-48-06.gh-issue-114328.hixxW3.rst new file mode 100644 index 00000000000..42262c05fd1 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2024-01-19-15-48-06.gh-issue-114328.hixxW3.rst @@ -0,0 +1,4 @@ +The :func:`tty.setcbreak` and new :func:`tty.cfmakecbreak` no longer clears +the terminal input ICRLF flag. This fixes a regression introduced in 3.12 +that no longer matched how OSes define cbreak mode in their ``stty(1)`` +manual pages.