prog1 | prog2 . How not to make prog2 block if not piped?
I googled around, but couldn't understand how to solve this problem. I have 2 scripts # script1.py # print 'something' #script2.py x=sys.stdin.read() print 'passed' if I run script1.py | script2.py all goes well. But if I run just script2.py the program blocks waiting forever for input. On *nix I used select.select to solve this problem, but on windows? I read that maybe I should use, from win32api, GetStdHandle and WaitForMultipleObjects, but how to do it it's far from my knowledge. Any help? Thank you, Riccardo -- http://mail.python.org/mailman/listinfo/python-list
Re: prog1 | prog2 . How not to make prog2 block if not piped?
Le Mercredi 14 Juin 2006 17:13, [EMAIL PROTECTED] a écrit :
# script1.py #
print 'something'
#script2.py
x=sys.stdin.read()
read() will read a file object to the end, i guess you want to use readline()
instead or the builtin raw_input.
print 'passed'
if I run
script1.py | script2.py
all goes well.
This is because when script1.py ends, it will send an 'EOF' char to
script2.py, wich terminate the read method.
But if I run just
script2.py
the program blocks waiting forever for input.
here, newlines ('\n'), doesn't terminate the read call, you can stop the read
by typing ctrl+d at the beginnning of a new line in a normal unix terminal.
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Re: prog1 | prog2 . How not to make prog2 block if not piped?
do u really need read something even when you run the scripts2.py directly? why not just change script2.py to #script2.py if __name__ == __main__: x=sys.stdin.read() print 'passed' else: print 'passed from else branch' is it what you want? or anything i misunderstand. On 14 Jun 2006 08:13:04 -0700, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: I googled around, but couldn't understand how to solve this problem. I have 2 scripts # script1.py # print 'something' #script2.py x=sys.stdin.read() print 'passed' if I run script1.py | script2.py all goes well. But if I run just script2.py the program blocks waiting forever for input. On *nix I used select.select to solve this problem, but on windows? I read that maybe I should use, from win32api, GetStdHandle and WaitForMultipleObjects, but how to do it it's far from my knowledge. Any help? Thank you, Riccardo -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: prog1 | prog2 . How not to make prog2 block if not piped?
imcs ee ha scritto: do u really need read something even when you run the scripts2.py directly? why not just change script2.py to #script2.py if __name__ == __main__: x=sys.stdin.read() print 'passed' else: print 'passed from else branch' is it what you want? or anything i misunderstand. it won't do. clever btw. Script2 is not a module, it's a program that _could_ receive input via pipe. -- http://mail.python.org/mailman/listinfo/python-list
Re: prog1 | prog2 . How not to make prog2 block if not piped?
yeah, forget my post ,it;s useless. sorry for my thoughtless On 14 Jun 2006 10:40:15 -0700, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: imcs ee ha scritto: do u really need read something even when you run the scripts2.py directly? why not just change script2.py to #script2.py if __name__ == __main__: x=sys.stdin.read() print 'passed' else: print 'passed from else branch' is it what you want? or anything i misunderstand. it won't do. clever btw. Script2 is not a module, it's a program that _could_ receive input via pipe. -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: prog1 | prog2 . How not to make prog2 block if not piped?
imcs ee wrote: yeah, forget my post ,it;s useless. sorry for my thoughtless On 14 Jun 2006 10:40:15 -0700, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: imcs ee ha scritto: do u really need read something even when you run the scripts2.py directly? why not just change script2.py to #script2.py if __name__ == __main__: x=sys.stdin.read() print 'passed' else: print 'passed from else branch' is it what you want? or anything i misunderstand. it won't do. clever btw. Script2 is not a module, it's a program that _could_ receive input via pipe. It really doesn't matter *how* it receives input, whether from a pipe, or a terminal or a redirected file. When you run it standalone you should give it some input - type some text then enter ^D (on Unix-like systems) or ^Z (on Windows). How else do you expect read() to return anything? It *has* to read to the end fo the file before it returns a value. regards Steve -- Steve Holden +44 150 684 7255 +1 800 494 3119 Holden Web LLC/Ltd http://www.holdenweb.com Love me, love my blog http://holdenweb.blogspot.com Recent Ramblings http://del.icio.us/steve.holden -- http://mail.python.org/mailman/listinfo/python-list
Re: prog1 | prog2 . How not to make prog2 block if not piped?
Steve Holden ha scritto: When you run it standalone you should give it some input - type some text then enter ^D (on Unix-like systems) or ^Z (on Windows). How else do you expect read() to return anything? It *has* to read to the end fo the file before it returns a value. regards Steve you've got reason. I must read my command line options, if then there is still text I use that, otherwise I read from stdin. If nothing was piped, the user must complete the work. Thank you all, Riccardo -- http://mail.python.org/mailman/listinfo/python-list
