On Thu, Mar 4, 2010 at 10:39 AM, Pete Emerson <pemer...@gmail.com> wrote:
>
> #!/usr/bin/python
>
More common:
#!/usr/bin/env python
> import sys, fileinput, re, os
>
> filename = '/etc/hosts'
>
> hosts = []
>
> for line in open(filename, 'r'):
> match = re.search('\d+\.\d+\.\d+\.\d+\s+(\S+)', line)
> if match is None or re.search('^(?:float|localhost)\.', line):
> continue
> hostname = match.group(1)
In Python, we use REs as a last resort. See "dir("")" or "help("")"
for why we don't use REs if we can avoid them.
The above is better represented with:
try:
ipaddr, hostnames = line.split(None, 1)
except IndexError:
continue
if line.find('float') >=0 or line.find('localhost') >= 0:
continue
> count = 0
> for arg in sys.argv[1:]:
> for section in hostname.split('.'):
> if section == arg:
> count = count + 1
> break
> if count == len(sys.argv) - 1:
> hosts.append(hostname)
>
You can use the "else" in a "for". as well.
for arg in sys.argv[1:]:
for section in hostname.split('.'):
if section == arg:
break
else: # Run only if for completes naturally
hosts.append(hostname)
It may be clearer to do set arithmetic as well.
> if len(hosts) == 1:
> os.system("ssh -A " + hosts[0])
You probably want one of the os.exec* methods instead, since you
aren't going to do anything after this.
> else:
> print '\n'.join(hosts)
Rather, the idiom is usually:
for host in hosts:
print host
--
Jonathan Gardner
jgard...@jonathangardner.net
--
http://mail.python.org/mailman/listinfo/python-list
