I have a build where two concurrent Python processes are both building C extension modules using distutils in the same directory. I have a "python setup.py build_ext" and a "python synch_setup.py build_ext" both in the same directory. Each setup.py refers to different files that need to be built, but occasionally one of the builds fails because it fails when executing mkdir("build"). With two concurrent distutils building in the same directory, there is a race condition when making the "build" directories. Here is an excerpt from dir_util.py: if not dry_run: try: os.mkdir(head) created_dirs.append(head) except OSError, exc: raise DistutilsFileError, \ "could not create '%s': %s" % (head, exc[-1]) mkdir can fail for two reasons -- one because the directory already exists and two because it couldn't create the directory. It would be nice if the except clause would ignore the failure when the directory already exists by testing if the directory exists and is accessible. This would prevent one of the setup.py's from stopping when it could really safely continue. I am not a member of the distutils-sig mailing list, so please Cc me on replies. Thanks, Tom -- ------------------------------------------------------------------------ Tom Epperly Center for Applied Scientific Computing Phone: 925-424-3159 Lawrence Livermore National Laboratory Fax: 925-424-2477 L-661, P.O. Box 808, Livermore, CA 94551 Email: tepperly@llnl.gov ------------------------------------------------------------------------