Bug in py32win manual for file_locking for Python 2.4

[Pekka Niiranen]

Hi,

I tried to lock file in w2k using example
directly from pyWin32 manual:

#--------------

import pywintypes
ov=pywintypes.OVERLAPPED() #used to indicate starting region to lock
highbits=0xffff0000
file="c:\\\\wilma.txt"
import win32file
import win32security
import win32api
secur_att = win32security.SECURITY_ATTRIBUTES()
secur_att.Initialize()
hfile=win32file.CreateFile( file, \ .... win32con.GENERIC_READ|win32con.GENERIC_WRITE, \
.... win32con.FILE_SHARE_READ|win32con.FILE_SHARE_WRITE , \
.... secur_att, \
.... win32con.OPEN_ALWAYS, \
.... win32con.FILE_ATTRIBUTE_NORMAL , 0 )

win32file.LockFileEx(hfile,win32con.LOCKFILE_EXCLU SIVE_LOCK,0,highbits,ov)
Traceback (most recent call last):
File "<interactive input>", line 1, in ?
OverflowError: long int too large to convert to int
#-------------

However, using
highbits=0x7fff0000 # equals hex(sys.maxint)
gives no errors, but does locking work if
highbits are not exactly 0xffff0000?

Does anybody have example of locking the whole directory
in one go without looping thru its files?

-pekka-

[Nick Coghlan]

Pekka Niiranen wrote:

However, using
highbits=0x7fff0000 # equals hex(sys.maxint)
gives no errors, but does locking work if
highbits are not exactly 0xffff0000?

Try using highbits=-0x7fff0000 as your mask. That should set the MSB without
tripping over the sys.maxint limit.

Cheers,
Nick.