ref: ce062debb1edaa27548deea0f151a9d4c95414a7
dir: /sys/lib/python/dircache.py/
"""Read and cache directory listings. The listdir() routine returns a sorted list of the files in a directory, using a cache to avoid reading the directory more often than necessary. The annotate() routine appends slashes to directories.""" import os __all__ = ["listdir", "opendir", "annotate", "reset"] cache = {} def reset(): """Reset the cache completely.""" global cache cache = {} def listdir(path): """List directory contents, using cache.""" try: cached_mtime, list = cache[path] del cache[path] except KeyError: cached_mtime, list = -1, [] mtime = os.stat(path).st_mtime if mtime != cached_mtime: list = os.listdir(path) list.sort() cache[path] = mtime, list return list opendir = listdir # XXX backward compatibility def annotate(head, list): """Add '/' suffixes to directories.""" for i in range(len(list)): if os.path.isdir(os.path.join(head, list[i])): list[i] = list[i] + '/'