Source Code for Module glue.utils

 1  # Copyright (C) 2010  Peter Couvares 
 2  # 
 3  # This program is free software; you can redistribute it and/or modify it 
 4  # under the terms of the GNU General Public License as published by the 
 5  # Free Software Foundation; either version 2 of the License, or (at your 
 6  # option) any later version. 
 7  # 
 8  # This program is distributed in the hope that it will be useful, but 
 9  # WITHOUT ANY WARRANTY; without even the implied warranty of 
10  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General 
11  # Public License for more details. 
12  # 
13  # You should have received a copy of the GNU General Public License along 
14  # with this program; if not, write to the Free Software Foundation, Inc., 
15  # 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA. 
16   
17   
18  import os 
19  import errno 
20   
21   
22  """ 
23  Check for pid existence efficiently and reliably.  (Using the null 
24  signal is faster and more unix-portable than looking in /proc). 
25   
26  Inspired by Larz Wirzenius 
27  <http://stackoverflow.com/questions/1005972> 
28  """ 
29 -def pid_exists(pid): 
30      """ Returns true if the given pid exists, false otherwise. """ 
31      try: 
32          # signal 0 is harmless and can be safely used to probe pid existence 
33          # faster and more unix-portable than looking in /proc 
34          os.kill(pid, 0) 
35      except OSError as e: 
36          # "permission denied" proves existence; otherwise, no such pid 
37          return e.errno == errno.EPERM 
38      else: 
39          return True 
40   
41   
42  """ 
43  Performs the equivalent of "mkdir -p", creating any intermediate 
44  directories needed to create the leaf directory -- but unlike 
45  os.makedirs(), produces no error if the path already exists. 
46   
47  Inspired by Christos Georgiou 
48  <http://stackoverflow.com/questions/600268/mkdir-p-functionality-in-python> 
49  """ 
50 -def mkdir_p(path): 
51      try: 
52          os.makedirs(path) 
53      except OSError as exc: 
54          if exc.errno == errno.EEXIST: 
55              pass 
56          else: raise 
57      return path 
58