diff options
Diffstat (limited to 'contrib/tools/python3/Lib/multiprocessing/shared_memory.py')
| -rw-r--r-- | contrib/tools/python3/Lib/multiprocessing/shared_memory.py | 24 |
1 files changed, 17 insertions, 7 deletions
diff --git a/contrib/tools/python3/Lib/multiprocessing/shared_memory.py b/contrib/tools/python3/Lib/multiprocessing/shared_memory.py index 9a1e5aa17b8..67e70fdc27c 100644 --- a/contrib/tools/python3/Lib/multiprocessing/shared_memory.py +++ b/contrib/tools/python3/Lib/multiprocessing/shared_memory.py @@ -71,8 +71,9 @@ class SharedMemory: _flags = os.O_RDWR _mode = 0o600 _prepend_leading_slash = True if _USE_POSIX else False + _track = True - def __init__(self, name=None, create=False, size=0): + def __init__(self, name=None, create=False, size=0, *, track=True): if not size >= 0: raise ValueError("'size' must be a positive integer") if create: @@ -82,6 +83,7 @@ class SharedMemory: if name is None and not self._flags & os.O_EXCL: raise ValueError("'name' can only be None if create=True") + self._track = track if _USE_POSIX: # POSIX Shared Memory @@ -116,8 +118,8 @@ class SharedMemory: except OSError: self.unlink() raise - - resource_tracker.register(self._name, "shared_memory") + if self._track: + resource_tracker.register(self._name, "shared_memory") else: @@ -236,12 +238,20 @@ class SharedMemory: def unlink(self): """Requests that the underlying shared memory block be destroyed. - In order to ensure proper cleanup of resources, unlink should be - called once (and only once) across all processes which have access - to the shared memory block.""" + Unlink should be called once (and only once) across all handles + which have access to the shared memory block, even if these + handles belong to different processes. Closing and unlinking may + happen in any order, but trying to access data inside a shared + memory block after unlinking may result in memory errors, + depending on platform. + + This method has no effect on Windows, where the only way to + delete a shared memory block is to close all handles.""" + if _USE_POSIX and self._name: _posixshmem.shm_unlink(self._name) - resource_tracker.unregister(self._name, "shared_memory") + if self._track: + resource_tracker.unregister(self._name, "shared_memory") _encoding = "utf8" |