Source Code for Module gmisclib.do_exec

 1  """Execute a *nix command  and capture the output.""" 
 2   
 3  import os 
 4  import re 
 5   
 6  __version__ = "$Revision: 1.5 $" 
 7  _comment = re.compile("\\s*#"); 
 8   
 9   
10 -def getall(s): 
11          """Read a list of lines from a process, after 
12          dropping junk like comments (beginning with whitespace then '#') 
13          or blank lines. 
14          Raises an exception if if the process returns 
15          a line beginning with 'ERR:' 
16          The argument s is a string containing the command and its  
17          arguments.  S is normally passed to a shell.""" 
18   
19          pipe = os.popen(s, 'r') 
20   
21          if pipe is None: 
22                  raise RuntimeError, 'Cannot spawn pipe for {%s}'%s 
23   
24          x = [] 
25          while 1: 
26                  line = pipe.readline(); 
27                  if line == '' : 
28                          break 
29                  if line.startswith('#'): 
30                          continue 
31                  cs = _comment.search(line) 
32                  if cs is not None :     # Strip off the comment. 
33                          line = cs.string[:cs.start()] 
34                  line = line.rstrip() 
35                  if line == '': 
36                          continue 
37                  if line.startswith('ERR:'): 
38                          raise RuntimeError, '%s from {%s}' % (line, s) 
39                  x.append(line.strip()) 
40           
41          sts = pipe.close() 
42          if sts is None: sts = 0 
43          if sts != 0 : 
44                  raise RuntimeError, \ 
45                          'spawned command fails with %d from {%s}' % (sts, s) 
46          return x 
47   
48   
49 -def get(s): 
50          """Read a single line from a process, after 
51          dropping junk like comments (#) or blank lines. 
52          Returns a trouble indication if the process returns 
53          'ERR:' """ 
54          x = getall(s) 
55          if len(x) < 1: 
56                  raise RuntimeError, 'no output fron {%s}' % s 
57          return x[0] 
58