posix: deprecate "nonblocking" method

3 files changed, 9 insertions, 10 deletions

diff --git a/documentation/pyserial_api.rst b/documentation/pyserial_api.rst
index 6e9cf20..75e19e7 100644
--- a/documentation/pyserial_api.rst
+++ b/documentation/pyserial_api.rst
@@ -485,9 +485,10 @@ Native ports
 
         :platform: Posix
 
-        Configure the device for nonblocking operation. This can be useful if
-        the port is used with :mod:`select`. Note that :attr:`timeout` must
-        also be set to ``0``
+        .. deprecated:: 3.2
+           The serial port is already opened in this mode. This method is not
+           needed and going away.
+
 
     .. method:: fileno()
 
diff --git a/serial/aio.py b/serial/aio.py
index b3238db..5756be0 100644
--- a/serial/aio.py
+++ b/serial/aio.py
@@ -52,7 +52,6 @@ class SerialTransport(asyncio.Transport):
         # Asynchronous I/O requires non-blocking devices
         self._serial.timeout = 0
         self._serial.write_timeout = 0
-        self._serial.nonblocking()
 
         # These two callbacks will be enqueued in a FIFO queue by asyncio
         loop.call_soon(protocol.connection_made, self)
diff --git a/serial/serialposix.py b/serial/serialposix.py
index 28164d8..bc2468c 100644
--- a/serial/serialposix.py
+++ b/serial/serialposix.py
@@ -635,12 +635,6 @@ class Serial(SerialBase, PlatformSpecific):
         s = fcntl.ioctl(self.fd, TIOCOUTQ, TIOCM_zero_str)
         return struct.unpack('I', s)[0]
 
-    def nonblocking(self):
-        """internal - not portable!"""
-        if not self.is_open:
-            raise portNotOpenError
-        fcntl.fcntl(self.fd, fcntl.F_SETFL, os.O_NONBLOCK)
-
     def fileno(self):
         """\
         For easier use of the serial port instance with select.
@@ -676,6 +670,11 @@ class Serial(SerialBase, PlatformSpecific):
         else:
             termios.tcflow(self.fd, termios.TCOOFF)
 
+    def nonblocking(self):
+        """DEPRECATED - has no use"""
+        import warnings
+        warnings.warn("nonblocking() has no effect, already nonblocking", DeprecationWarning)
+
 
 class PosixPollSerial(Serial):
     """\