author | Sverre Rabbelier <srabbelier@gmail.com> |
Thu, 05 Feb 2009 23:46:39 +0000 | |
changeset 1228 | b24796279fb9 |
parent 323 | ff1a9aa48cfd |
permissions | -rw-r--r-- |
323
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Load ../vendor/django into trunk/app/django.
Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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1 |
""" |
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Load ../vendor/django into trunk/app/django.
Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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2 |
Portable file locking utilities. |
ff1a9aa48cfd
Load ../vendor/django into trunk/app/django.
Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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3 |
|
ff1a9aa48cfd
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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4 |
Based partially on example by Jonathan Feignberg <jdf@pobox.com> in the Python |
ff1a9aa48cfd
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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5 |
Cookbook, licensed under the Python Software License. |
ff1a9aa48cfd
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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6 |
|
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Load ../vendor/django into trunk/app/django.
Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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7 |
http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/65203 |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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8 |
|
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Load ../vendor/django into trunk/app/django.
Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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9 |
Example Usage:: |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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10 |
|
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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11 |
>>> from django.core.files import locks |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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>>> f = open('./file', 'wb') |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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13 |
>>> locks.lock(f, locks.LOCK_EX) |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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14 |
>>> f.write('Django') |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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15 |
>>> f.close() |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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16 |
""" |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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17 |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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18 |
__all__ = ('LOCK_EX','LOCK_SH','LOCK_NB','lock','unlock') |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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|
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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system_type = None |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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21 |
|
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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22 |
try: |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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23 |
import win32con |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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24 |
import win32file |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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25 |
import pywintypes |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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26 |
LOCK_EX = win32con.LOCKFILE_EXCLUSIVE_LOCK |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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27 |
LOCK_SH = 0 |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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28 |
LOCK_NB = win32con.LOCKFILE_FAIL_IMMEDIATELY |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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__overlapped = pywintypes.OVERLAPPED() |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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system_type = 'nt' |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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except (ImportError, AttributeError): |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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32 |
pass |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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|
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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34 |
try: |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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import fcntl |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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36 |
LOCK_EX = fcntl.LOCK_EX |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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LOCK_SH = fcntl.LOCK_SH |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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LOCK_NB = fcntl.LOCK_NB |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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39 |
system_type = 'posix' |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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40 |
except (ImportError, AttributeError): |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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41 |
pass |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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|
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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def fd(f): |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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"""Get a filedescriptor from something which could be a file or an fd.""" |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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return hasattr(f, 'fileno') and f.fileno() or f |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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|
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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47 |
if system_type == 'nt': |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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def lock(file, flags): |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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hfile = win32file._get_osfhandle(fd(file)) |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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win32file.LockFileEx(hfile, flags, 0, -0x10000, __overlapped) |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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|
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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def unlock(file): |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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hfile = win32file._get_osfhandle(fd(file)) |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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win32file.UnlockFileEx(hfile, 0, -0x10000, __overlapped) |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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elif system_type == 'posix': |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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def lock(file, flags): |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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fcntl.lockf(fd(file), flags) |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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|
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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def unlock(file): |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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fcntl.lockf(fd(file), fcntl.LOCK_UN) |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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else: |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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# File locking is not supported. |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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63 |
LOCK_EX = LOCK_SH = LOCK_NB = None |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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|
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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# Dummy functions that don't do anything. |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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def lock(file, flags): |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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67 |
pass |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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68 |
|
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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def unlock(file): |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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70 |
pass |