On 2/07/2006 5:02 AM, Christoph Haas wrote: > Hi... > > I encountered a problem that - according to my google search - other > people have found, too. Example code: > > import sys > for line in sys.stdin: > print line > > Running this code in Python 2.3 or 2.4 has the problem that I need to > send two EOFs (Ctrl-D) to break out of that loop. > > Use case is a piped Python script that I run as a "CustomLog" pipe for > an Apache web server. I want to run all the log output through that pipe > but haven't had much luck. First it takes ages until the script > processes the input (even though I ran Python with "-u" to make it > unbuffered)
Which "it" did you expect to make unbuffered? -u unbuffers sys.stdout and sys.stderr (and makes them binary, which wouldn't be a good idea on a Windows box). If you are concerned that output shows up in real time, use sys.stdXXX.flush(). > and then the script needs one EOF to do something with the > input and a second EOF to break out of the loop. > > Is this a bug? I'm close to write a Perl script for this case. :( I can reproduce your problem on Windows with Python 2.4.2 (note ^Z is EOF for Windows): |>> import sys |>> for line in sys.stdin: ... print >> sys.stderr, "->", repr(line) ... line1 line2 line3 ^Z -> 'line1\n' -> 'line2\n' -> 'line3\n' ^Z |>> However this worked for me : |>> import sys |>> while 1: ... line = sys.stdin.readline() ... if not line: break ... print >> sys.stderr, "->", repr(line) ... line1 -> 'line1\n' line2 -> 'line2\n' ^Z |>> The Library Reference Manual, section 2.3.9 (File Objects) says: """ Files support the iterator protocol. Each iteration returns the same result as file.readline(), and iteration ends when the readline() method returns an empty string. """ So yes, looks like a bug to me, but perhaps you don't need use Perl :-) HTH, John -- http://mail.python.org/mailman/listinfo/python-list
