昨天 Python释放了 3.5 ，添加了 os.scandir 根据文档该API比os.listdir快Docs

which speeds it up by 3-5 times on POSIX systems and by 7-20 times on Windows systems

以前因为目录太大(文件数过万)，listdir又太慢，写了一个自己的listdir,发布一下 (仅支持Linux)

#!/usr/bin/python

import os

import ctypes

from ctypes.util import find_library

clib = ctypes.CDLL(find_library('C'))

class c_dir(ctypes.Structure):

	pass

class c_dirent(ctypes.Structure):

	_fields_ = (

		('d_ino', ctypes.c_long),

		('d_off', ctypes.c_long), # offset

		('d_reclen', ctypes.c_ushort), # record length

		('d_type', ctypes.c_byte),

		('d_name', ctypes.c_char *4096),

	)

c_dir_p = ctypes.POINTER(c_dir)

c_dirent_p = ctypes.POINTER(c_dirent)

opendir, readdir, closedir = clib.opendir, clib.readdir, clib.closedir

opendir.argtypes = [ ctypes.c_char_p ]

opendir.restype = c_dir_p

readdir.argtypes = [ c_dir_p ]

readdir.restype = c_dirent_p

closedir.argtypes = [ c_dir_p ]

closedir.restype = ctypes.c_int

def countdir(path):

	if not os.path.isdir(path):

		raise ValueError('arg error, not a dir: '+path)

	dirfd = opendir(path)

	total_num, total_filename, total_metasize = 0, 0, 0

	try:

		while True:

			entry = readdir(dirfd)

			if not entry:

				break

			total_filename += len(entry.contents.d_name)

			total_metasize += entry.contents.d_reclen

			total_num += 1

	finally:

		closedir(dirfd)

	return {"count":total_num-2, "total_filename":total_filename, "total_metasize":total_metasize,"dirsize":os.path.getsize(path)}

def listdir(path):

	'include two special dirs: . and .. '

	if not os.path.isdir(path):

		raise ValueError('arg error, not a dir: '+path)

	dirfd = opendir(path)

	try:

		while True:

			entry = readdir(dirfd)

			if not entry:

				break

			yield {"name":entry.contents.d_name,

				"inode": entry.contents.d_ino,

				"metasize":entry.contents.d_reclen}

	finally:

		closedir(dirfd)

if __name__ == '__main__':

	import sys

	i = 0

	total = 0

	path = sys.argv[1]

	print( countdir(path) )

	# for entry in listdir(path):

		# print(entry['name'], entry['metasize'])

		# total += entry['metasize']

	# print('total:', total, 'dir size: ', os.path.getsize(path))