1  # encoding: utf-8
   2  """
   3  Utilities for working with external processes.
   4  """
   5  
   6  # Copyright (c) IPython Development Team.
   7  # Distributed under the terms of the Modified BSD License.
   8  
   9  
  10  import os
  11  import shutil
  12  import sys
  13  
  14  if sys.platform == 'win32':
  15      from ._process_win32 import system, getoutput, arg_split, check_pid
  16  elif sys.platform == 'cli':
  17      from ._process_cli import system, getoutput, arg_split, check_pid
  18  elif sys.platform == "emscripten":
  19      from ._process_emscripten import system, getoutput, arg_split, check_pid
  20  else:
  21      from ._process_posix import system, getoutput, arg_split, check_pid
  22  
  23  from ._process_common import getoutputerror, get_output_error_code, process_handler
  24  
  25  
  26  class FindCmdError(Exception):
  27      pass
  28  
  29  
  30  def find_cmd(cmd):
  31      """Find absolute path to executable cmd in a cross platform manner.
  32  
  33      This function tries to determine the full path to a command line program
  34      using `which` on Unix/Linux/OS X and `win32api` on Windows.  Most of the
  35      time it will use the version that is first on the users `PATH`.
  36  
  37      Warning, don't use this to find IPython command line programs as there
  38      is a risk you will find the wrong one.  Instead find those using the
  39      following code and looking for the application itself::
  40  
  41          import sys
  42          argv = [sys.executable, '-m', 'IPython']
  43  
  44      Parameters
  45      ----------
  46      cmd : str
  47          The command line program to look for.
  48      """
  49      path = shutil.which(cmd)
  50      if path is None:
  51          raise FindCmdError('command could not be found: %s' % cmd)
  52      return path
  53  
  54  
  55  def abbrev_cwd():
  56      """ Return abbreviated version of cwd, e.g. d:mydir """
  57      cwd = os.getcwd().replace('\\','/')
  58      drivepart = ''
  59      tail = cwd
  60      if sys.platform == 'win32':
  61          if len(cwd) < 4:
  62              return cwd
  63          drivepart,tail = os.path.splitdrive(cwd)
  64  
  65  
  66      parts = tail.split('/')
  67      if len(parts) > 2:
  68          tail = '/'.join(parts[-2:])
  69  
  70      return (drivepart + (
  71          cwd == '/' and '/' or tail))
  72