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 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
python类O_EXCL的实例源码
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, 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, 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, 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 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, 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, 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, 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, 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, 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 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, 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, 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, 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, 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, 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, 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 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 touch(self, mode=0o666, exist_ok=True):
"""
Create this file with the given access mode, if it doesn't exist.
"""
if exist_ok:
# First try to bump modification time
# Implementation note: GNU touch uses the UTIME_NOW option of
# the utimensat() / futimens() functions.
t = time.time()
try:
self._accessor.utime(self, (t, t))
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)
