| """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 subprocess |
| |
| from distutils.errors import DistutilsExecError |
| from distutils.debug import DEBUG |
| from distutils import log |
| |
| |
| def spawn(cmd, search_path=1, verbose=0, dry_run=0, env=None): |
| """Run another program, specified as a command list 'cmd', in a new process. |
| |
| 'cmd' is just the argument list for the new process, ie. |
| cmd[0] is the program to run and cmd[1:] are the rest of its arguments. |
| There is no way to run a program with a name different from that of its |
| executable. |
| |
| If 'search_path' is true (the default), the system's executable |
| search path will be used to find the program; otherwise, cmd[0] |
| must be the exact path to the executable. If 'dry_run' is true, |
| the command will not actually be run. |
| |
| Raise DistutilsExecError if running the program fails in any way; just |
| return on success. |
| """ |
| # cmd is documented as a list, but just in case some code passes a tuple |
| # in, protect our %-formatting code against horrible death |
| cmd = list(cmd) |
| |
| log.info(subprocess.list2cmdline(cmd)) |
| if dry_run: |
| return |
| |
| if search_path: |
| executable = find_executable(cmd[0]) |
| if executable is not None: |
| cmd[0] = executable |
| |
| env = env if env is not None else dict(os.environ) |
| |
| if sys.platform == 'darwin': |
| from distutils.util import MACOSX_VERSION_VAR, get_macosx_target_ver |
| |
| macosx_target_ver = get_macosx_target_ver() |
| if macosx_target_ver: |
| env[MACOSX_VERSION_VAR] = macosx_target_ver |
| |
| try: |
| proc = subprocess.Popen(cmd, env=env) |
| proc.wait() |
| exitcode = proc.returncode |
| except OSError as exc: |
| if not DEBUG: |
| cmd = cmd[0] |
| raise DistutilsExecError("command %r failed: %s" % (cmd, exc.args[-1])) from exc |
| |
| if exitcode: |
| if not DEBUG: |
| cmd = cmd[0] |
| raise DistutilsExecError( |
| "command %r failed with exit code %s" % (cmd, exitcode) |
| ) |
| |
| |
| 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 |