diff --git a/Doc/library/io.rst b/Doc/library/io.rst
index 7eec1f87583b87..04cb4a5fc36ed7 100644
--- a/Doc/library/io.rst
+++ b/Doc/library/io.rst
@@ -168,6 +168,19 @@ High-level Module Interface
    :func:`os.stat`) if possible.
 
 
+.. data:: SEEK_SET
+          SEEK_CUR
+          SEEK_END
+
+   Parameters to the :meth:`~IOBase.seek` method,
+   used to specify the relative position
+   Their values are 0, 1, and 2, respectively.
+
+   .. seealso::
+
+      :data:`os.SEEK_SET`, :data:`os.SEEK_CUR`, and :data:`os.SEEK_END`.
+
+
 .. function:: open(file, mode='r', buffering=-1, encoding=None, errors=None, newline=None, closefd=True, opener=None)
 
    This is an alias for the builtin :func:`open` function.
@@ -405,18 +418,17 @@ I/O Base Classes
 
    .. method:: seek(offset, whence=SEEK_SET, /)
 
-      Change the stream position to the given byte *offset*.  *offset* is
-      interpreted relative to the position indicated by *whence*.  The default
-      value for *whence* is :data:`SEEK_SET`.  Values for *whence* are:
+      Change the stream position to the given byte *offset*,
+      and return the new absolute position as an integer.
+      *offset* is interpreted relative to the position indicated by *whence*.
+      Valid values for *whence* are:
 
-      * :data:`SEEK_SET` or ``0`` -- start of the stream (the default);
+      * :data:`SEEK_SET` -- seek from the start of the stream (the default);
         *offset* should be zero or positive
-      * :data:`SEEK_CUR` or ``1`` -- current stream position; *offset* may
-        be negative
-      * :data:`SEEK_END` or ``2`` -- end of the stream; *offset* is usually
-        negative
-
-      Return the new absolute position.
+      * :data:`SEEK_CUR` -- seek from current stream position;
+        *offset* may be negative
+      * :data:`SEEK_END` -- seek from the end of the stream;
+        *offset* is usually negative
 
       .. versionadded:: 3.1
          The ``SEEK_*`` constants.
@@ -911,21 +923,22 @@ Text I/O
 
    .. method:: seek(offset, whence=SEEK_SET, /)
 
-      Change the stream position to the given *offset*.  Behaviour depends on
-      the *whence* parameter.  The default value for *whence* is
-      :data:`SEEK_SET`.
-
-      * :data:`SEEK_SET` or ``0``: seek from the start of the stream
-        (the default); *offset* must either be a number returned by
-        :meth:`TextIOBase.tell`, or zero.  Any other *offset* value
-        produces undefined behaviour.
-      * :data:`SEEK_CUR` or ``1``: "seek" to the current position;
-        *offset* must be zero, which is a no-operation (all other values
-        are unsupported).
-      * :data:`SEEK_END` or ``2``: seek to the end of the stream;
-        *offset* must be zero (all other values are unsupported).
-
-      Return the new absolute position as an opaque number.
+      Change the stream position to the given byte *offset*,
+      and return the new absolute position as an opaque number.
+      *offset* is interpreted relative to the position indicated by *whence*.
+      Valid values for *whence* are:
+
+      * :data:`SEEK_SET` -- seek from the start of the stream (the default);
+        *offset* must either be a number returned by
+        :meth:`TextIOBase.tell`, or zero.
+        Any other *offset* value produces undefined behaviour.
+      * :data:`SEEK_CUR` -- seek from current stream position;
+        *offset* must be zero, which is a no-operation.
+        All other values are unsupported.
+      * :data:`SEEK_END` -- seek from the end of the stream;
+        *offset* must be zero.
+        All other values are unsupported.
+
 
       .. versionadded:: 3.1
          The ``SEEK_*`` constants.
diff --git a/Doc/tutorial/inputoutput.rst b/Doc/tutorial/inputoutput.rst
index f5cdd84cbadefe..5c415563d7ced7 100644
--- a/Doc/tutorial/inputoutput.rst
+++ b/Doc/tutorial/inputoutput.rst
@@ -433,10 +433,12 @@ an opaque number when in text mode.
 
 To change the file object's position, use ``f.seek(offset, whence)``.  The position is computed
 from adding *offset* to a reference point; the reference point is selected by
-the *whence* argument.  A *whence* value of 0 measures from the beginning
-of the file, 1 uses the current file position, and 2 uses the end of the file as
-the reference point.  *whence* can be omitted and defaults to 0, using the
-beginning of the file as the reference point. ::
+the *whence* argument.
+A *whence* value of :data:`io.SEEK_SET` measures from the beginning of the file,
+:data:`io.SEEK_CUR` uses the current file position,
+and :data:`io.SEEK_END` uses the end of the file as the reference point.
+*whence* can be omitted and defaults to :data:`!io.SEEK_SET`,
+using the beginning of the file as the reference point. ::
 
    >>> f = open('workfile', 'rb+')
    >>> f.write(b'0123456789abcdef')
@@ -445,14 +447,14 @@ beginning of the file as the reference point. ::
    5
    >>> f.read(1)
    b'5'
-   >>> f.seek(-3, 2)  # Go to the 3rd byte before the end
+   >>> f.seek(-3, io.SEEK_END)  # Go to the 3rd byte before the end
    13
    >>> f.read(1)
    b'd'
 
 In text files (those opened without a ``b`` in the mode string), only seeks
 relative to the beginning of the file are allowed (the exception being seeking
-to the very file end with ``seek(0, 2)``) and the only valid *offset* values are
+to the very file end with ``seek(0, io.SEEK_END)``) and the only valid *offset* values are
 those returned from the ``f.tell()``, or zero. Any other *offset* value produces
 undefined behaviour.
 
diff --git a/Doc/whatsnew/3.1.rst b/Doc/whatsnew/3.1.rst
index c399f007fd63fb..b4ab0181d04ad9 100644
--- a/Doc/whatsnew/3.1.rst
+++ b/Doc/whatsnew/3.1.rst
@@ -367,8 +367,8 @@ New, Improved, and Deprecated Modules
 
   (Contributed by Benjamin Peterson and Antoine Pitrou.)
 
-* The :mod:`io` module has three new constants for the :meth:`seek`
-  method :data:`SEEK_SET`, :data:`SEEK_CUR`, and :data:`SEEK_END`.
+* The :mod:`io` module has three new constants for the :meth:`~io.IOBase.seek`
+  method :data:`~io.SEEK_SET`, :data:`~io.SEEK_CUR`, and :data:`~io.SEEK_END`.
 
 * The :data:`sys.version_info` tuple is now a named tuple::
 
diff --git a/Modules/_io/bufferedio.c b/Modules/_io/bufferedio.c
index 0983a7bd151f40..c13c16268d7637 100644
--- a/Modules/_io/bufferedio.c
+++ b/Modules/_io/bufferedio.c
@@ -1284,14 +1284,14 @@ _io__Buffered_tell_impl(buffered *self)
 
 /*[clinic input]
 _io._Buffered.seek
-    target as targetobj: object
-    whence: int = 0
+    offset as targetobj: object
+    whence: int(c_default='0') = io.SEEK_SET
     /
 [clinic start generated code]*/
 
 static PyObject *
 _io__Buffered_seek_impl(buffered *self, PyObject *targetobj, int whence)
-/*[clinic end generated code: output=7ae0e8dc46efdefb input=a9c4920bfcba6163]*/
+/*[clinic end generated code: output=7ae0e8dc46efdefb input=d9ac57b8f178bc05]*/
 {
     Py_off_t target, n;
     PyObject *res = NULL;
diff --git a/Modules/_io/bytesio.c b/Modules/_io/bytesio.c
index 3ab503c9e3998d..f6fcc9445c0f66 100644
--- a/Modules/_io/bytesio.c
+++ b/Modules/_io/bytesio.c
@@ -636,22 +636,18 @@ bytesio_iternext(bytesio *self)
 
 /*[clinic input]
 _io.BytesIO.seek
-    pos: Py_ssize_t
-    whence: int = 0
+    offset as pos: Py_ssize_t
+    whence: int(c_default='0') = io.SEEK_SET
     /
 
-Change stream position.
+Change stream position and return the new absolute position.
 
-Seek to byte offset pos relative to position indicated by whence:
-     0  Start of stream (the default).  pos should be >= 0;
-     1  Current position - pos may be negative;
-     2  End of stream - pos usually negative.
-Returns the new absolute position.
+Set the byte offset 'offset', relative to position indicated by 'whence':
 [clinic start generated code]*/
 
 static PyObject *
 _io_BytesIO_seek_impl(bytesio *self, Py_ssize_t pos, int whence)
-/*[clinic end generated code: output=c26204a68e9190e4 input=1e875e6ebc652948]*/
+/*[clinic end generated code: output=c26204a68e9190e4 input=dbeeba9f5f031b6e]*/
 {
     CHECK_CLOSED(self);
 
diff --git a/Modules/_io/clinic/bufferedio.c.h b/Modules/_io/clinic/bufferedio.c.h
index 4f40fdadf8ec85..671a4162b8226b 100644
--- a/Modules/_io/clinic/bufferedio.c.h
+++ b/Modules/_io/clinic/bufferedio.c.h
@@ -697,7 +697,7 @@ _io__Buffered_tell(buffered *self, PyObject *Py_UNUSED(ignored))
 }
 
 PyDoc_STRVAR(_io__Buffered_seek__doc__,
-"seek($self, target, whence=0, /)\n"
+"seek($self, offset, whence=io.SEEK_SET, /)\n"
 "--\n"
 "\n");
 
@@ -1098,4 +1098,4 @@ _io_BufferedRandom___init__(PyObject *self, PyObject *args, PyObject *kwargs)
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=b7ddf84a5bc2bf34 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=24202f17f6d2f4f7 input=a9049054013a1b77]*/
diff --git a/Modules/_io/clinic/bytesio.c.h b/Modules/_io/clinic/bytesio.c.h
index 9550c8728c251e..b7678ae8e0ee5f 100644
--- a/Modules/_io/clinic/bytesio.c.h
+++ b/Modules/_io/clinic/bytesio.c.h
@@ -385,16 +385,12 @@ _io_BytesIO_truncate(bytesio *self, PyObject *const *args, Py_ssize_t nargs)
 }
 
 PyDoc_STRVAR(_io_BytesIO_seek__doc__,
-"seek($self, pos, whence=0, /)\n"
+"seek($self, offset, whence=io.SEEK_SET, /)\n"
 "--\n"
 "\n"
-"Change stream position.\n"
+"Change stream position and return the new absolute position.\n"
 "\n"
-"Seek to byte offset pos relative to position indicated by whence:\n"
-"     0  Start of stream (the default).  pos should be >= 0;\n"
-"     1  Current position - pos may be negative;\n"
-"     2  End of stream - pos usually negative.\n"
-"Returns the new absolute position.");
+"Set the byte offset \'offset\', relative to position indicated by \'whence\':");
 
 #define _IO_BYTESIO_SEEK_METHODDEF    \
     {"seek", _PyCFunction_CAST(_io_BytesIO_seek), METH_FASTCALL, _io_BytesIO_seek__doc__},
@@ -538,4 +534,4 @@ _io_BytesIO___init__(PyObject *self, PyObject *args, PyObject *kwargs)
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=098584d485420b65 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=f9239531031159de input=a9049054013a1b77]*/
diff --git a/Modules/_io/clinic/fileio.c.h b/Modules/_io/clinic/fileio.c.h
index 33a37a389d223d..e97508d5b0af1d 100644
--- a/Modules/_io/clinic/fileio.c.h
+++ b/Modules/_io/clinic/fileio.c.h
@@ -397,18 +397,9 @@ _io_FileIO_write(fileio *self, PyTypeObject *cls, PyObject *const *args, Py_ssiz
 }
 
 PyDoc_STRVAR(_io_FileIO_seek__doc__,
-"seek($self, pos, whence=0, /)\n"
+"seek($self, offset, whence=io.SEEK_SET, /)\n"
 "--\n"
-"\n"
-"Move to new file position and return the file position.\n"
-"\n"
-"Argument offset is a byte count.  Optional argument whence defaults to\n"
-"SEEK_SET or 0 (offset from start of file, offset should be >= 0); other values\n"
-"are SEEK_CUR or 1 (move relative to current position, positive or negative),\n"
-"and SEEK_END or 2 (move relative to end of file, usually negative, although\n"
-"many platforms allow seeking beyond the end of a file).\n"
-"\n"
-"Note that not all file objects are seekable.");
+"\n");
 
 #define _IO_FILEIO_SEEK_METHODDEF    \
     {"seek", _PyCFunction_CAST(_io_FileIO_seek), METH_FASTCALL, _io_FileIO_seek__doc__},
@@ -421,7 +412,7 @@ _io_FileIO_seek(fileio *self, PyObject *const *args, Py_ssize_t nargs)
 {
     PyObject *return_value = NULL;
     PyObject *pos;
-    int whence = 0;
+    int whence = SEEK_SET;
 
     if (!_PyArg_CheckPositional("seek", nargs, 1, 2)) {
         goto exit;
@@ -536,4 +527,4 @@ _io_FileIO_isatty(fileio *self, PyObject *Py_UNUSED(ignored))
 #ifndef _IO_FILEIO_TRUNCATE_METHODDEF
     #define _IO_FILEIO_TRUNCATE_METHODDEF
 #endif /* !defined(_IO_FILEIO_TRUNCATE_METHODDEF) */
-/*[clinic end generated code: output=bef47b31b644996a input=a9049054013a1b77]*/
+/*[clinic end generated code: output=7450ee2e06306599 input=a9049054013a1b77]*/
diff --git a/Modules/_io/clinic/iobase.c.h b/Modules/_io/clinic/iobase.c.h
index 773e0010477053..6d0a794596496e 100644
--- a/Modules/_io/clinic/iobase.c.h
+++ b/Modules/_io/clinic/iobase.c.h
@@ -9,19 +9,28 @@ preserve
 
 
 PyDoc_STRVAR(_io__IOBase_seek__doc__,
-"seek($self, offset, whence=os.SEEK_SET, /)\n"
+"seek($self, offset, whence=io.SEEK_SET, /)\n"
 "--\n"
 "\n"
-"Change the stream position to the given byte offset.\n"
+"Change the stream position and return the new absolute position.\n"
 "\n"
-"The offset is interpreted relative to the position indicated by whence.\n"
-"Values for whence are:\n"
+"  offset\n"
+"    Offset as byte count.\n"
+"    Relative to the position given by \'whence\'.\n"
+"  whence\n"
+"    Relative position, used by \'offset\'. Valid values are:\n"
+"    * io.SEEK_SET -- Start of stream (the default)\n"
+"    * io.SEEK_CUR -- Current position\n"
+"    * io.SEEK_END -- End of stream\n"
 "\n"
-"* os.SEEK_SET or 0 -- start of stream (the default); offset should be zero or positive\n"
-"* os.SEEK_CUR or 1 -- current stream position; offset may be negative\n"
-"* os.SEEK_END or 2 -- end of stream; offset is usually negative\n"
+"Offsets relative to the start of the stream are usually zero or\n"
+"positive, offsets relative to the current stream position may be\n"
+"zero, positive or negative, and offsets relative to the end of the\n"
+"stream are usually zero or negative.\n"
 "\n"
-"Return the new absolute position.");
+"Some platforms allow seeking beyond the end of a file.\n"
+"\n"
+"Note that not all file objects are seekable.");
 
 #define _IO__IOBASE_SEEK_METHODDEF    \
     {"seek", _PyCFunction_CAST(_io__IOBase_seek), METH_METHOD|METH_FASTCALL|METH_KEYWORDS, _io__IOBase_seek__doc__},
@@ -436,4 +445,4 @@ _io__RawIOBase_readall(PyObject *self, PyObject *Py_UNUSED(ignored))
 {
     return _io__RawIOBase_readall_impl(self);
 }
-/*[clinic end generated code: output=301b22f8f75ce3dc input=a9049054013a1b77]*/
+/*[clinic end generated code: output=386caf503869c9c2 input=a9049054013a1b77]*/
diff --git a/Modules/_io/clinic/stringio.c.h b/Modules/_io/clinic/stringio.c.h
index d495dd10c16330..f5c2362b87d2b5 100644
--- a/Modules/_io/clinic/stringio.c.h
+++ b/Modules/_io/clinic/stringio.c.h
@@ -156,16 +156,18 @@ _io_StringIO_truncate(stringio *self, PyObject *const *args, Py_ssize_t nargs)
 }
 
 PyDoc_STRVAR(_io_StringIO_seek__doc__,
-"seek($self, pos, whence=0, /)\n"
+"seek($self, offset, whence=io.SEEK_SET, /)\n"
 "--\n"
 "\n"
-"Change stream position.\n"
+"Change the stream position and return the new absolute position.\n"
 "\n"
-"Seek to character offset pos relative to position indicated by whence:\n"
-"    0  Start of stream (the default).  pos should be >= 0;\n"
-"    1  Current position - pos must be 0;\n"
-"    2  End of stream - pos must be 0.\n"
-"Returns the new absolute position.");
+"Offsets relative to the start of the stream are usually zero or positive.\n"
+"Offsets relative to the current and end of file positions must zero;\n"
+"any other values are unsupported, and will raise OSError.\n"
+"\n"
+"Some platforms allow seeking beyond the end of a file.\n"
+"\n"
+"Note that not all file objects are seekable.");
 
 #define _IO_STRINGIO_SEEK_METHODDEF    \
     {"seek", _PyCFunction_CAST(_io_StringIO_seek), METH_FASTCALL, _io_StringIO_seek__doc__},
@@ -367,4 +369,4 @@ _io_StringIO_seekable(stringio *self, PyObject *Py_UNUSED(ignored))
 {
     return _io_StringIO_seekable_impl(self);
 }
-/*[clinic end generated code: output=533f20ae9b773126 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=e57b92b21538d3df input=a9049054013a1b77]*/
diff --git a/Modules/_io/clinic/textio.c.h b/Modules/_io/clinic/textio.c.h
index 5c2162529ff2dd..c59d3c6cf42d3c 100644
--- a/Modules/_io/clinic/textio.c.h
+++ b/Modules/_io/clinic/textio.c.h
@@ -756,9 +756,19 @@ _io_TextIOWrapper_readline(textio *self, PyObject *const *args, Py_ssize_t nargs
 }
 
 PyDoc_STRVAR(_io_TextIOWrapper_seek__doc__,
-"seek($self, cookie, whence=0, /)\n"
+"seek($self, offset, whence=io.SEEK_SET, /)\n"
 "--\n"
-"\n");
+"\n"
+"Change the file position and return the new absolute position.\n"
+"\n"
+"Offsets relative to the start of the file are usually zero or positive.\n"
+"Offsets relative to the current and end of file positions must zero;\n"
+"any other values are unsupported, and will raise the\n"
+"io.UnsupportedOperation exception.\n"
+"\n"
+"Some platforms allow seeking beyond the end of a file.\n"
+"\n"
+"Note that not all file objects are seekable.");
 
 #define _IO_TEXTIOWRAPPER_SEEK_METHODDEF    \
     {"seek", _PyCFunction_CAST(_io_TextIOWrapper_seek), METH_FASTCALL, _io_TextIOWrapper_seek__doc__},
@@ -957,4 +967,4 @@ _io_TextIOWrapper_close(textio *self, PyObject *Py_UNUSED(ignored))
 {
     return _io_TextIOWrapper_close_impl(self);
 }
-/*[clinic end generated code: output=e1060638b65e8a63 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=6bdd72dabb204764 input=a9049054013a1b77]*/
diff --git a/Modules/_io/fileio.c b/Modules/_io/fileio.c
index 7fe37eee787e50..fe923c02e5bb0b 100644
--- a/Modules/_io/fileio.c
+++ b/Modules/_io/fileio.c
@@ -953,24 +953,14 @@ portable_lseek(fileio *self, PyObject *posobj, int whence, bool suppress_pipe_er
 
 /*[clinic input]
 _io.FileIO.seek
-    pos: object
-    whence: int = 0
+    offset as pos: object
+    whence: int(c_default='SEEK_SET') = io.SEEK_SET
     /
-
-Move to new file position and return the file position.
-
-Argument offset is a byte count.  Optional argument whence defaults to
-SEEK_SET or 0 (offset from start of file, offset should be >= 0); other values
-are SEEK_CUR or 1 (move relative to current position, positive or negative),
-and SEEK_END or 2 (move relative to end of file, usually negative, although
-many platforms allow seeking beyond the end of a file).
-
-Note that not all file objects are seekable.
 [clinic start generated code]*/
 
 static PyObject *
 _io_FileIO_seek_impl(fileio *self, PyObject *pos, int whence)
-/*[clinic end generated code: output=c976acdf054e6655 input=0439194b0774d454]*/
+/*[clinic end generated code: output=c976acdf054e6655 input=ec74977caf7c656b]*/
 {
     if (self->fd < 0)
         return err_closed();
diff --git a/Modules/_io/iobase.c b/Modules/_io/iobase.c
index 5fd19895311c0c..647afbba868c91 100644
--- a/Modules/_io/iobase.c
+++ b/Modules/_io/iobase.c
@@ -83,25 +83,31 @@ iobase_unsupported(_PyIO_State *state, const char *message)
 _io._IOBase.seek
     cls: defining_class
     offset: int(unused=True)
-    whence: int(unused=True, c_default='0') = os.SEEK_SET
+      Offset as byte count.
+      Relative to the position given by 'whence'.
+    whence: int(unused=True, c_default='0') = io.SEEK_SET
+      Relative position, used by 'offset'. Valid values are:
+      * io.SEEK_SET -- Start of stream (the default)
+      * io.SEEK_CUR -- Current position
+      * io.SEEK_END -- End of stream
     /
 
-Change the stream position to the given byte offset.
+Change the stream position and return the new absolute position.
 
-The offset is interpreted relative to the position indicated by whence.
-Values for whence are:
+Offsets relative to the start of the stream are usually zero or
+positive, offsets relative to the current stream position may be
+zero, positive or negative, and offsets relative to the end of the
+stream are usually zero or negative.
 
-* os.SEEK_SET or 0 -- start of stream (the default); offset should be zero or positive
-* os.SEEK_CUR or 1 -- current stream position; offset may be negative
-* os.SEEK_END or 2 -- end of stream; offset is usually negative
+Some platforms allow seeking beyond the end of a file.
 
-Return the new absolute position.
+Note that not all file objects are seekable.
 [clinic start generated code]*/
 
 static PyObject *
 _io__IOBase_seek_impl(PyObject *self, PyTypeObject *cls,
                       int Py_UNUSED(offset), int Py_UNUSED(whence))
-/*[clinic end generated code: output=8bd74ea6538ded53 input=8d4e6adcd08292f2]*/
+/*[clinic end generated code: output=8bd74ea6538ded53 input=bcdff2c6dd398df8]*/
 {
     _PyIO_State *state = get_io_state_by_cls(cls);
     return iobase_unsupported(state, "seek");
diff --git a/Modules/_io/stringio.c b/Modules/_io/stringio.c
index 1856b07108bab6..0e0f36994bb08a 100644
--- a/Modules/_io/stringio.c
+++ b/Modules/_io/stringio.c
@@ -463,22 +463,24 @@ _io_StringIO_truncate_impl(stringio *self, Py_ssize_t size)
 
 /*[clinic input]
 _io.StringIO.seek
-    pos: Py_ssize_t
-    whence: int = 0
+    offset as pos: Py_ssize_t
+    whence: int(c_default='0') = io.SEEK_SET
     /
 
-Change stream position.
+Change the stream position and return the new absolute position.
 
-Seek to character offset pos relative to position indicated by whence:
-    0  Start of stream (the default).  pos should be >= 0;
-    1  Current position - pos must be 0;
-    2  End of stream - pos must be 0.
-Returns the new absolute position.
+Offsets relative to the start of the stream are usually zero or positive.
+Offsets relative to the current and end of file positions must zero;
+any other values are unsupported, and will raise OSError.
+
+Some platforms allow seeking beyond the end of a file.
+
+Note that not all file objects are seekable.
 [clinic start generated code]*/
 
 static PyObject *
 _io_StringIO_seek_impl(stringio *self, Py_ssize_t pos, int whence)
-/*[clinic end generated code: output=e9e0ac9a8ae71c25 input=e3855b24e7cae06a]*/
+/*[clinic end generated code: output=e9e0ac9a8ae71c25 input=50823fbdc8782825]*/
 {
     CHECK_INITIALIZED(self);
     CHECK_CLOSED(self);
diff --git a/Modules/_io/textio.c b/Modules/_io/textio.c
index 6ce90b2ed774c0..27a3cf6744c28f 100644
--- a/Modules/_io/textio.c
+++ b/Modules/_io/textio.c
@@ -2427,14 +2427,25 @@ _textiowrapper_encoder_setstate(textio *self, cookie_type *cookie)
 
 /*[clinic input]
 _io.TextIOWrapper.seek
-    cookie as cookieObj: object
-    whence: int = 0
+    offset as cookieObj: object
+    whence: int(c_default='0') = io.SEEK_SET
     /
+
+Change the file position and return the new absolute position.
+
+Offsets relative to the start of the file are usually zero or positive.
+Offsets relative to the current and end of file positions must zero;
+any other values are unsupported, and will raise the
+io.UnsupportedOperation exception.
+
+Some platforms allow seeking beyond the end of a file.
+
+Note that not all file objects are seekable.
 [clinic start generated code]*/
 
 static PyObject *
 _io_TextIOWrapper_seek_impl(textio *self, PyObject *cookieObj, int whence)
-/*[clinic end generated code: output=0a15679764e2d04d input=0458abeb3d7842be]*/
+/*[clinic end generated code: output=0a15679764e2d04d input=35d7e7156afb3e56]*/
 {
     PyObject *posobj;
     cookie_type cookie;