#16937: document that stdin is always buffered, even when -u is used. Patch by Elena Oat.
diff --git a/Doc/using/cmdline.rst b/Doc/using/cmdline.rst
index e0c80f6..f2d2616 100644
--- a/Doc/using/cmdline.rst
+++ b/Doc/using/cmdline.rst
@@ -269,8 +269,8 @@
.. cmdoption:: -u
- Force the binary layer of the stdin, stdout and stderr streams (which is
- available as their ``buffer`` attribute) to be unbuffered. The text I/O
+ Force the binary layer of the stdout and stderr streams (which is
+ available as their ``buffer`` attribute) to be unbuffered. The text I/O
layer will still be line-buffered if writing to the console, or
block-buffered if redirected to a non-interactive file.
diff --git a/Misc/ACKS b/Misc/ACKS
index c85b437..288f186 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -896,6 +896,7 @@
Zooko O'Whielacronx
Aaron Oakley
James Oakley
+Elena Oat
Jon Oberheide
Pascal Oberndoerfer
Jeffrey Ollie
diff --git a/Misc/python.man b/Misc/python.man
index 8155e6a..bcb3ec8 100644
--- a/Misc/python.man
+++ b/Misc/python.man
@@ -172,7 +172,8 @@
is explicitly imported later.
.TP
.B \-u
-Force the binary I/O layers of stdin, stdout and stderr to be unbuffered.
+Force the binary I/O layers of stdout and stderr to be unbuffered.
+stdin is always buffered.
The text I/O layer will still be line-buffered.
.\" Note that there is internal buffering in readlines() and
.\" file-object iterators ("for line in sys.stdin") which is not
diff --git a/Modules/main.c b/Modules/main.c
index 4d2e03a..3cfc9c3 100644
--- a/Modules/main.c
+++ b/Modules/main.c
@@ -77,7 +77,8 @@
-S : don't imply 'import site' on initialization\n\
";
static char *usage_3 = "\
--u : unbuffered binary stdout and stderr; also PYTHONUNBUFFERED=x\n\
+-u : unbuffered binary stdout and stderr, stdin always buffered;\n\
+ also PYTHONUNBUFFERED=x\n\
see man page for details on internal buffering relating to '-u'\n\
-v : verbose (trace import statements); also PYTHONVERBOSE=x\n\
can be supplied multiple times to increase verbosity\n\