Maximum read size for sys.stdin

[Brian Quinlan]

Does anyone have an explanation for why stdin has a maximum read size on
Windows?

>>> sys.stdin.read(10000)
^Z
''
>>> sys.stdin.read(100000)
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
IOError: [Errno 12] Not enough space

Cheers,
Brian