windows下python檢查文件是否被其它文件打開.md

有時候我們需要能夠判斷一個文件是否正在被其它文件訪問，幾乎不可避免的要調用操作系統接口

from ctypes import cdll
import os

_sopen = cdll.msvcrt._sopen
_close = cdll.msvcrt._close
_SH_DENYRW = 0x10

def is_open(filename):
    if not os.access(filename, os.F_OK):
        return False # file doesn't exist
    h = _sopen(filename, 0, _SH_DENYRW, 0)
    if h == 3:
        _close(h)
        return False # file is not opened by anyone else
    return True # file is already open

print is_open("test.txt")

ref:
http://stackoverflow.com/questions/8231719/how-to-check-whether-a-file-is-open-and-the-open-status-in-python