Bad pipe filedescriptor when reading from stdin in python

Question

Duplicate of this question. Vote to close.

Consider this at the windows commandline.

scriptA.py | scriptB.py

In scriptA.py:

sys.stdout.write( "hello" )

In scriptB.py:

print sys.stdin.read()

This generates the following error:

c:\> scriptA.py | scriptB.py
close failed: [Errno 22] Invalid argument
Traceback (most recent call last):
  File "c:\scriptB.py", line 20, in <module>
    print sys.stdin.read()
IOError: [Errno 9] Bad file descriptor

The "close failed" message seems to come from execution of scriptA.py.

It doesn't matter if I use sys.stdin.read(), sys.stdin.read(1), sys.stdin.readlines() etc etc.

What's wrong?

Duplicate of this question. Vote to close.

I just tried it with python a.py | python b.py , which works fine. See Johan's answer for the reason. — balpha
– balpha ♦, Commented Jun 29, 2009 at 10:51

Johan · Accepted Answer · 2009-06-29 12:09:29Z

7

It seems that stdin/stdout redirect does not work when starting from a file association. This is not specific to python, but a problem caused by win32 cmd.exe.

See: http://mail.python.org/pipermail/python-bugs-list/2004-August/024920.html

edited Jun 29, 2009 at 12:09

answered Jun 29, 2009 at 10:48

Johan

3,0891 gold badge22 silver badges15 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

John Machin Over a year ago

Please consider editing your response so that it states that the problem is in Windows CMD.EXE, not in Python.

sdaau Over a year ago

Not sure if this problem is really Windows specific, as I just encountered something similar on Linux - see my entry Linux: Pipe into Python (ncurses) script, stdin and termios - Stack Overflow

Collectives™ on Stack Overflow

Bad pipe filedescriptor when reading from stdin in python

1 Answer 1

2 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related