| """distutils.spawn |
| |
| Provides the 'spawn()' function, a front-end to various platform- |
| specific functions for launching another program in a sub-process. |
| Also provides the 'find_executable()' to search the path for a given |
| executable name. |
| """ |
| |
| import sys |
| import os |
| import os.path |
| |
| |
| def find_executable(executable, path=None): |
| """Tries to find 'executable' in the directories listed in 'path'. |
| |
| A string listing directories separated by 'os.pathsep'; defaults to |
| os.environ['PATH']. Returns the complete filename or None if not found. |
| """ |
| _, ext = os.path.splitext(executable) |
| if (sys.platform == 'win32') and (ext != '.exe'): |
| executable = executable + '.exe' |
| |
| if os.path.isfile(executable): |
| return executable |
| |
| if path is None: |
| path = os.environ.get('PATH', None) |
| if path is None: |
| try: |
| path = os.confstr("CS_PATH") |
| except (AttributeError, ValueError): |
| # os.confstr() or CS_PATH is not available |
| path = os.defpath |
| # bpo-35755: Don't use os.defpath if the PATH environment variable is |
| # set to an empty string |
| |
| # PATH='' doesn't match, whereas PATH=':' looks in the current directory |
| if not path: |
| return None |
| |
| paths = path.split(os.pathsep) |
| for p in paths: |
| f = os.path.join(p, executable) |
| if os.path.isfile(f): |
| # the file exists, we have a shot at spawn working |
| return f |
| return None |
