Python piping on Windows: Why does this not work?

I'm trying something like this

Output.py

print "Hello"

Input.py

greeting = raw_input("Give me the greeting. ")
print "The greeting is:", greeting

At the cmd line

Output.py | Input.py

But it returns an EOFError. Can someone tell me what I am doing wrong?

Thanks for your help.

EDIT
Patrick Harrington solution works but I don't know why...

From stackoverflow

• I tested this on my Windows machine and it works if you specify the Python exe:

  C:\>C:\Python25\python.exe output.py | C:\Python25\python.exe input.py
  Give me the greeting. The greeting is: hello
  

  But I get an EOFError also if running the commands directly as:

  output.py | input.py
  

  I'm not sure exactly why that is, I'm still looking into this one but at least this should provide you with a workaround for now. It may have something to do with the way the file handler is invoked for .py files.

  UPDATE: well, what do you know. Looks like this is actually a bug in Windows where stdin/stdout redirection may not work properly when started from a file association. So the workaround is as noted by myself and Patrick, you need to specify "python" will be running input.py, otherwise it will not redirect stdout from output.py to the stdin for input.py correctly.

  Reference:

  http://mail.python.org/pipermail/python-bugs-list/2004-August/024923.html

  http://support.microsoft.com/default.aspx?kbid=321788

  UPDATE 2:

  To change this behavior and make Windows pipes work as expected for stdin/stdout redirection, you can add this value to the registry (tested on my box and verified this works as desired).

  1. Start Registry Editor.

  2. Locate and then click the following key in the registry:

     HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer

  3. On the Edit menu, click Add Value, and then add the following registry value:

     Value name: InheritConsoleHandles
     Data type: *REG_DWORD*
     Radix: Decimal
     Value data: 1

  4. Quit Registry Editor.

  J.F. Sebastian : It is worth mentioning that now you can add `InheritConsoleHandles` value to Windows registry to use `output.py | input.py` as described in the linked microsoft.com page.

  Jay : good point, will do

• Change it to:

  Output.py | python Input.py
  

  The output will be:

  Give me the greeting. The greeting is: hello

  Casey : why does this work but leaving out python makes it not work?

  Jay : See my answer for the reason why this works.

• Here's why you get the EOFError (from the documentation on raw_input):

  The function then reads a line from input, converts it to a string (stripping a trailing newline), and returns that. When EOF is read, EOFError is raised.

  http://docs.python.org/library/functions.html?highlight=raw_input#raw_input

  You may want to use sys.stdin, it provides a file object from which you can use the read, readlines methods.

  import sys
  for greeting_line in sys.stdin.readlines():
      print "The greeting is:", greeting_line.strip()