In article <cd1be83a-f560-4024-90b3-697a51bb1...@g7g2000vbv.googlegroups.com>, Jean Dubois <jeandubois...@gmail.com> wrote:
> I'm writing some code to check whether an url is available or not, > therefore I make use of a wget-command in Linux and then check whether > this is successful In general, "shelling out" to run a command-line utility should be the last resort. It's slower, and more complicated, than doing it in pure python. You would only call a shell command if there was no other way. Fortunately, in Python, there is another way. Several, in fact. The most straight-forward is to use the built-in urllib2 module (http://docs.python.org/2/library/urllib2.html). If you're going to be doing anything complicated (i.e. setting optional headers, managing cookies, etc), you probably want to be looking at the excellent third-party module, requests (http://python-requests.org). In any case, given your code: > #!/usr/bin/env python > import sys > import os > from datetime import datetime, timedelta > today=datetime.now() > yesterday= datetime.now() - timedelta(days=1) > daybeforeyesterday= datetime.now() - timedelta(days=2) > collection = [daybeforeyesterday,yesterday,today] > for thisday in collection: > checkavailablestring='wget -q -O - > http://www.deredactie.be/cm/vrtnieuws/videozone/programmas/journaal/EP_'+thisd > ay.strftime("%y%m%d")+'_JO7 > >/dev/null ; echo $?' > if os.system(checkavailablestring)==0: > print thisday, 'stream is available' > else: > print thisday, 'stream is not available' I would break the debugging down into several parts. First, are you generating the command string properly? Try printing out checkavailablestring before you call os.system() to make sure it's what you think it is. Next, once you're sure you've got the correct string, run it manually in the shell and see what it does. Next, are you sure you're using os.system() correctly? Try running: os.system("/bin/true") and os.system("/bin/false") and make sure you get the results you think you should. But, really, once you've done all that (and it's worth doing as an exercise), rewrite your code to use urllib2 or requests. It'll be a lot easier. -- http://mail.python.org/mailman/listinfo/python-list
