Lib/idlelib/spawn.py

   1 # spawn - This is ugly, OS-specific code to spawn a separate process.  It
   2 #         also defines a function for getting the version of a path most
   3 #         likely to work with cranky API functions.
   4
   5 import os
   6
   7 def hardpath(path):
   8     path = os.path.normcase(os.path.abspath(path))
   9     try:
  10         import win32api
  11         path = win32api.GetShortPathName( path )
  12     except:
  13         pass
  14     return path
  15
  16 if hasattr(os, 'fork'):
  17
  18   # UNIX-ish operating system: we fork() and exec(), and we have to track
  19   #   the pids of our children and call waitpid() on them to avoid leaving
  20   #   zombies in the process table.  kill_zombies() does the dirty work, and
  21   #   should be called periodically.
  22
  23   zombies = []
  24
  25   def spawn(bin, *args):
  26     pid = os.fork()
  27     if pid:
  28       zombies.append(pid)
  29     else:
  30       os.execv( bin, (bin, ) + args )
  31
  32   def kill_zombies():
  33       for z in zombies[:]:
  34           stat = os.waitpid(z, os.WNOHANG)
  35           if stat[0]==z:
  36               zombies.remove(z)
  37 elif hasattr(os, 'spawnv'):
  38
  39   # Windows-ish OS: we use spawnv(), and stick quotes around arguments
  40   #   in case they contains spaces, since Windows will jam all the
  41   #   arguments to spawn() or exec() together into one string.  The
  42   #   kill_zombies function is a noop.
  43
  44   def spawn(bin, *args):
  45     nargs = [bin]
  46     for arg in args:
  47       nargs.append( '"'+arg+'"' )
  48     os.spawnv( os.P_NOWAIT, bin, nargs )
  49
  50   def kill_zombies(): pass
  51
  52 else:
  53   # If you get here, you may be able to write an alternative implementation
  54   # of these functions for your OS.
  55
  56   def kill_zombies(): pass
  57
  58   raise OSError, 'This OS does not support fork() or spawnv().'