Python os 模块，O_CREAT 实例源码
我们从Python开源项目中，提取了以下50个代码示例，用于说明如何使用os.O_CREAT。
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path, open_flags, open_mode)
pidfile = os.fdopen(pidfile_fd, 'w')
# According to the FHS 2.3 section on PID files in /var/run:
#
# The file must consist of the process identifier in
# ASCII-encoded decimal,followed by a newline character. For
# example,if crond was process number 25,/var/run/crond.pid
# would contain three characters: two,five,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def writeKeyToFile(key, filename):
"""Write **key** to **filename**,with ``0400`` permissions.
If **filename** doesn't exist,it will be created. If it does exist
already,and is writable by the owner of the current process,then it will
be truncated to zero-length and overwritten.
:param bytes key: A key (or some other private data) to write to
**filename**.
:param str filename: The path of the file to write to.
:raises: Any exceptions which may occur.
"""
logging.info("Writing key to file: %r", filename)
flags = os.O_WRONLY | os.O_TRUNC | os.O_CREAT | getattr(os, "O_BIN", 0)
fd = os.open(filename, flags, 0400)
os.write(fd, key)
os.fsync(fd)
os.close(fd)
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def do_magic(self):
if OS_WIN:
try:
if os.path.exists(LOCK_PATH):
os.unlink(LOCK_PATH)
self.fh = os.open(LOCK_PATH, os.O_CREAT | os.O_EXCL | os.O_RDWR)
except EnvironmentError as err:
if err.errno == 13:
self.is_running = True
else:
raise
else:
try:
self.fh = open(LOCK_PATH, 'w')
fcntl.lockf(self.fh, fcntl.LOCK_EX | fcntl.LOCK_NB)
except EnvironmentError as err:
if self.fh is not None:
self.is_running = True
else:
raise
def wipe(self):
filter_bitmap_fd = os.open("/dev/shm/kafl_filter0", os.O_RDWR | os.O_SYNC | os.O_CREAT)
os.ftruncate(filter_bitmap_fd, self.config.config_values['BITMAP_SHM_SIZE'])
filter_bitmap = mmap.mmap(filter_bitmap_fd, self.config.config_values['BITMAP_SHM_SIZE'], mmap.MAP_SHARED, mmap.PROT_WRITE | mmap.PROT_READ)
for i in range(self.config.config_values['BITMAP_SHM_SIZE']):
filter_bitmap[i] = '\x00'
filter_bitmap.close()
os.close(filter_bitmap_fd)
filter_bitmap_fd = os.open("/dev/shm/kafl_tfilter", 0x1000000)
filter_bitmap = mmap.mmap(filter_bitmap_fd, 0x1000000, mmap.PROT_WRITE | mmap.PROT_READ)
for i in range(0x1000000):
filter_bitmap[i] = '\x00'
filter_bitmap.close()
os.close(filter_bitmap_fd)
def __set_binary(self, filename, binaryfile, max_size):
shm_fd = os.open(filename, os.O_RDWR | os.O_SYNC | os.O_CREAT)
os.ftruncate(shm_fd, max_size)
shm = mmap.mmap(shm_fd, max_size, mmap.PROT_WRITE | mmap.PROT_READ)
shm.seek(0x0)
shm.write('\x00' * max_size)
shm.seek(0x0)
f = open(binaryfile, "rb")
bytes = f.read(1024)
if bytes:
shm.write(bytes)
while bytes != "":
bytes = f.read(1024)
if bytes:
shm.write(bytes)
f.close()
shm.close()
os.close(shm_fd)
def init(self):
self.control = socket.socket(socket.AF_UNIX)
while True:
try:
self.control.connect(self.control_filename)
#self.control.connect(self.control_filename)
break
except socket_error:
pass
#time.sleep(0.01)
self.kafl_shm_f = os.open(self.bitmap_filename, os.O_RDWR | os.O_SYNC | os.O_CREAT)
self.fs_shm_f = os.open(self.payload_filename, os.O_RDWR | os.O_SYNC | os.O_CREAT)
#argv_fd = os.open(self.argv_filename,os.O_RDWR | os.O_SYNC | os.O_CREAT)
os.ftruncate(self.kafl_shm_f, self.bitmap_size)
os.ftruncate(self.fs_shm_f, (128 << 10))
#os.ftruncate(argv_fd,(4 << 10))
self.kafl_shm = mmap.mmap(self.kafl_shm_f, self.bitmap_size, mmap.PROT_WRITE | mmap.PROT_READ)
self.fs_shm = mmap.mmap(self.fs_shm_f, (128 << 10), mmap.MAP_SHARED, mmap.PROT_WRITE | mmap.PROT_READ)
return True
def writef_win32(f, data, m='w', encoding='ISO8859-1'):
if sys.hexversion > 0x3000000 and not 'b' in m:
data = data.encode(encoding)
m += 'b'
flags = os.O_CREAT | os.O_TRUNC | os.O_WRONLY | os.O_NOINHERIT
if 'b' in m:
flags |= os.O_BINARY
if '+' in m:
flags |= os.O_RDWR
try:
fd = os.open(f, flags)
except OSError:
raise IOError('Cannot write to %r' % f)
f = os.fdopen(fd, m)
try:
f.write(data)
finally:
f.close()
def writef_win32(f, m)
try:
f.write(data)
finally:
f.close()
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def setup_environment():
root = os.getenv('LAMBDA_TASK_ROOT')
bin_dir = os.path.join(root, 'bin')
os.environ['PATH'] += ':' + bin_dir
os.environ['GIT_EXEC_PATH'] = bin_dir
ssh_dir = tempfile.mkdtemp()
ssh_identity = os.path.join(ssh_dir, 'identity')
with os.fdopen(os.open(ssh_identity, os.O_WRONLY | os.O_CREAT, 0o600),
'w') as f:
f.write(base64.b64decode(os.getenv('SSH_IDENTITY')))
ssh_config = os.path.join(ssh_dir, 'config')
with open(ssh_config, 'w') as f:
f.write('CheckHostIP no\n'
'StrictHostKeyChecking yes\n'
'IdentityFile %s\n'
'UserKnownHostsFile %s\n' %
(ssh_identity, os.path.join(root, 'known_hosts')))
os.environ['GIT_SSH_COMMAND'] = 'ssh -F %s' % ssh_config
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def acquire(self, blocking=False):
import fcntl # @UnresolvedImport
flags = os.O_CREAT | os.O_WRONLY
self.fd = os.open(self.filename, flags)
mode = fcntl.LOCK_EX
if not blocking:
mode |= fcntl.LOCK_NB
try:
fcntl.flock(self.fd, mode)
self.locked = True
return True
except IOError:
e = sys.exc_info()[1]
if e.errno not in (errno.EAGAIN, errno.EACCES):
raise
os.close(self.fd)
self.fd = None
return False
def acquire(self, blocking=False):
import msvcrt # @UnresolvedImport
flags = os.O_CREAT | os.O_WRONLY
mode = msvcrt.LK_NBLCK
if blocking:
mode = msvcrt.LK_LOCK
self.fd = os.open(self.filename, flags)
try:
msvcrt.locking(self.fd, mode, 1)
return True
except IOError:
e = sys.exc_info()[1]
if e.errno not in (errno.EAGAIN, errno.EACCES, errno.EDEADLK):
raise
os.close(self.fd)
self.fd = None
return False
def create_file(self, name, excl=False, mode="wb", **kwargs):
"""Creates a file with the given name in this storage.
:param name: the name for the new file.
:param excl: if True,try to open the file in "exclusive" mode.
:param mode: the mode flags with which to open the file. The default is
``"wb"``.
:return: a :class:`whoosh.filedb.structfile.StructFile` instance.
"""
if self.readonly:
raise ReadOnlyError
path = self._fpath(name)
if excl:
flags = os.O_CREAT | os.O_EXCL | os.O_RDWR
if hasattr(os, "O_BINARY"):
flags |= os.O_BINARY
fd = os.open(path, flags)
fileobj = os.fdopen(fd, mode)
else:
fileobj = open(path, mode)
f = StructFile(fileobj, name=name, **kwargs)
return f
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def _convert_pflags(self, pflags):
"convert SFTP-style open() flags to python's os.open() flags"
if (pflags & SFTP_FLAG_READ) and (pflags & SFTP_FLAG_WRITE):
flags = os.O_RDWR
elif pflags & SFTP_FLAG_WRITE:
flags = os.O_WRONLY
else:
flags = os.O_RDONLY
if pflags & SFTP_FLAG_APPEND:
flags |= os.O_APPEND
if pflags & SFTP_FLAG_CREATE:
flags |= os.O_CREAT
if pflags & SFTP_FLAG_TRUNC:
flags |= os.O_TRUNC
if pflags & SFTP_FLAG_EXCL:
flags |= os.O_EXCL
return flags
def acquire(self):
""" Acquire the lock,if possible. If the lock is in use,it check again
every `wait` seconds. It does this until it either gets the lock or
exceeds `timeout` number of seconds,in which case it throws
an exception.
"""
start_time = time.time()
while True:
try:
self.fd = os.open(self.lockfile, os.O_CREAT|os.O_EXCL|os.O_RDWR)
break
except OSError as e:
if e.errno != errno.EEXIST:
raise
if (time.time() - start_time) >= self.timeout:
raise FileLockTimeoutException("%d seconds passed." % self.timeout)
time.sleep(self.delay)
self.is_locked = True
def acquire(self):
"""Acquire the lock file.
:raises errors.LockError: if lock is already held
:raises OSError: if unable to open or stat the lock file
"""
while self._fd is None:
# Open the file
fd = os.open(self._path, os.O_CREAT | os.O_WRONLY, 0o600)
try:
self._try_lock(fd)
if self._lock_success(fd):
self._fd = fd
finally:
# Close the file if it is not the required one
if self._fd is None:
os.close(fd)
def safe_open(path, mode="w", chmod=None, buffering=None):
"""Safely open a file.
:param str path: Path to a file.
:param str mode: Same os `mode` for `open`.
:param int chmod: Same as `mode` for `os.open`,uses Python defaults
if ``None``.
:param int buffering: Same as `bufsize` for `os.fdopen`,uses Python
defaults if ``None``.
"""
# pylint: disable=star-args
open_args = () if chmod is None else (chmod,)
fdopen_args = () if buffering is None else (buffering,)
return os.fdopen(
os.open(path, os.O_CREAT | os.O_EXCL | os.O_RDWR, *open_args),
mode, *fdopen_args)
def _init_dirs(self):
test_dirs = ['a a', 'b', 'c\c', 'D_']
config = 'improbable'
root = tempfile.mkdtemp()
def cleanup():
try:
os.removedirs(root)
except (FileNotFoundError, OSError):
pass
os.chdir(root)
for dir_ in test_dirs:
os.mkdir(dir_, 0o0750)
f = '{0}.toml'.format(config)
flags = os.O_WRONLY | os.O_CREAT
rel_path = '{0}/{1}'.format(dir_, f)
abs_file_path = os.path.join(root, rel_path)
with os.fdopen(os.open(abs_file_path, 0o0640), 'w') as fp:
fp.write("key = \"value is {0}\"\n".format(dir_))
return root, config, cleanup
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def touch(self, mode=0o666, exist_ok=True):
"""
Create this file with the given access mode,if it doesn't exist.
"""
if self._closed:
self._raise_closed()
if exist_ok:
# First try to bump modification time
# Implementation note: GNU touch uses the UTIME_NOW option of
# the utimensat() / futimens() functions.
try:
self._accessor.utime(self, None)
except OSError:
# Avoid exception chaining
pass
else:
return
flags = os.O_CREAT | os.O_WRONLY
if not exist_ok:
flags |= os.O_EXCL
fd = self._raw_open(flags, mode)
os.close(fd)
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def _obtain_lock_or_raise(self):
"""Create a lock file as flag for other instances,mark our instance as lock-holder
:raise IOError: if a lock was already present or a lock file could not be written"""
if self._has_lock():
return
lock_file = self._lock_file_path()
if osp.isfile(lock_file):
raise IOError("Lock for file %r did already exist,delete %r in case the lock is illegal" %
(self._file_path, lock_file))
try:
flags = os.O_WRONLY | os.O_CREAT | os.O_EXCL
if is_win:
flags |= os.O_SHORT_LIVED
fd = os.open(lock_file, 0)
os.close(fd)
except OSError as e:
raise IOError(str(e))
self._owns_lock = True
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def lock(lockfile):
def decorator(clbl):
def wrapper(*args, **kwargs):
try:
# Create or fail
os.open(lockfile, os.O_CREAT | os.O_EXCL)
except OSError:
raise BackupError(
"Another backup/restore process already running."
" If it is not,try to remove `{0}` and "
"try again.".format(lockfile))
try:
result = clbl(*args, **kwargs)
finally:
os.unlink(lockfile)
return result
return wrapper
return decorator
def lock(lockfile):
def decorator(clbl):
def wrapper(*args, **kwargs)
finally:
os.unlink(lockfile)
return result
return wrapper
return decorator
def lock(lockfile):
def decorator(clbl):
def wrapper(*args, os.O_CREAT | os.O_EXCL)
except OSError:
raise BackupError("Another backup process already running."
" If it is not,try to remove `{0}` and "
"try again.".format(lockfile))
try:
result = clbl(*args, **kwargs)
finally:
os.unlink(lockfile)
return result
return wrapper
return decorator
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def with_multi_lock(tag, n, unlock_after_with=True):
get_lock_file_path = lambda i: os.path.join(
'/tmp/', tag + '.lock' + (str(i) if i else ''))
for i in range(n):
lock_file_path = get_lock_file_path(i)
fd = os.open(lock_file_path, os.O_CREAT | os.O_RDWR, 0660)
try:
if trylock(fd):
yield True
break
finally:
if unlock_after_with:
os.close(fd)
else:
yield False
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def write_pid_to_pidfile(pidfile_path):
""" Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
"""
open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
open_mode = 0o644
pidfile_fd = os.open(pidfile_path,and newline.
pid = os.getpid()
pidfile.write("%s\n" % pid)
pidfile.close()
def _create_home(self):
if not os.path.isdir(self._HOME + '/' + self._CONFIG_DIR):
os.makedirs(self._HOME + '/' + self._CONFIG_DIR)
with os.fdopen(os.open(self._HOME + '/' + self._CONFIG_DIR + '/' + self._CONFIG_FILE_NAME,
os.O_WRONLY | os.O_CREAT, 'w'):
pass
with os.fdopen(os.open(self._HOME + '/' + self._CONFIG_DIR + '/' + self._CREDENTIALS_FILE_NAME, 'w'):
pass
def acquire(self, blocking=True):
"""Acquire the lock if possible.
If the lock is in use and ``blocking`` is ``False``,return
``False``.
Otherwise,check every `self.delay` seconds until it acquires
lock or exceeds `self.timeout` and raises an `~AcquisitionError`.
"""
start = time.time()
while True:
self._validate_lockfile()
try:
fd = os.open(self.lockfile, os.O_CREAT | os.O_EXCL | os.O_RDWR)
with os.fdopen(fd, 'w') as fd:
fd.write('{0}'.format(os.getpid()))
break
except OSError as err:
if err.errno != errno.EEXIST: # pragma: no cover
raise
if self.timeout and (time.time() - start) >= self.timeout:
raise AcquisitionError('Lock acquisition timed out.')
if not blocking:
return False
time.sleep(self.delay)
self._locked = True
return True