Windows max files

max_files.py

#!python
from __future__ import print_function
import os, io
import ctypes, logging
import win32file, win32con
import sys
logging.basicConfig()
log = logging.getLogger()
print("Max files before set {}".format(ctypes.windll.msvcrt._getmaxstdio()))
if sys.version_info.major == 2:
    if ctypes.windll.msvcr90._setmaxstdio(2048) == -1:
        print("Set max open files failed")
print("Max files after set {}".format(ctypes.windll.msvcr90._getmaxstdio()))

TRY_MAX = 1000000


def openfiles_builtin_open(max=TRY_MAX):
    print("Try builtin open: {}".format(max))
    files = {}
    try:
        for a in range(max):
            name = 'file_{}'.format(a)
            #files[name] = os.open(name, os.O_CREAT, 0x666)
            files[name] = open(name, 'w')
    except Exception as exc:
        print("Got exception {} at {}".format(repr(exc), a))
    finally:
        for name in files:
            files[name].close()
            try:
                os.remove(name)
            except:
                pass



def openfiles_createfile(max=TRY_MAX):
    print("Try CreateFile open: {}".format(max))
    files = {}
    try:
        for a in range(max):
            name = 'file_{}'.format(a)
            files[name] = win32file.CreateFile(name, 
                                      win32file.GENERIC_WRITE, 
                                      0, 
                                      None, 
                                      win32con.CREATE_NEW, 
                                      0, 
                                      None)
    except Exception as exc:
        print("Got exception {} at {}".format(repr(exc), a))
    finally:
        for name in files:
            files[name].Close()
            try:
                os.remove(name)
            except:
                pass


def openfiles_msvcrt__open(max=TRY_MAX):
    print("Try msvcrt._open open: {}".format(max))
    files = {}
    try:
        for a in range(max):
            name = 'file_{}'.format(a)
    except Exception as exc:
        print("Got exception {} at {}".format(repr(exc), a))
    finally:
        for name in files:
            ctypes.windll.msvcrt.fclose(files[name])
            try:
                os.remove(name)
            except:
                pass





def openfiles_c(max=204800):
    try:
        for a in range(max):
            name = 'file_{}'.format(a)
            #files[name] = io.open(name, 'w')
            files[name] = ctypes.windll.msvcrt._open(name)
        print("opened {}".format(max))
    finally:
        for name in files:
            ctypes.windll.msvcrt.fclose(files[name])
            try:
                os.remove(name)
            except:
                pass


openfiles_builtin_open()
openfiles_msvcrt__open()
openfiles_createfile()