def lock (self):
'''
Creates and holds on to the lock file with exclusive access.
Returns True if lock successful, False if it is not, and raises
an exception upon operating system errors encountered creating the
lock file.
'''
try:
#
# Create or else open and trucate lock file, in read-write mode.
#
# A crashed app might not delete the lock file, so the
# os.O_CREAT | os.O_EXCL combination that guarantees
# atomic create isn't useful here. That is, we don't want to
# fail locking just because the file exists.
#
# Could use os.O_EXLOCK, but that doesn't exist yet in my Python
#
self.lockfd = os.open (self.lockfile,
os.O_TRUNC | os.O_CREAT | os.O_RDWR)
# Acquire exclusive lock on the file, but don't block waiting for it
fcntl.flock (self.lockfd, fcntl.LOCK_EX | fcntl.LOCK_NB)
# Writing to file is pointless, nobody can see it
os.write (self.lockfd, "My Lockfile")
return True
except (OSError, IOError), e:
# Lock cannot be acquired is okay, everything else reraise exception
if e.errno in (errno.EACCES, errno.EAGAIN):
return False
else:
raise
python类O_TRUNC的实例源码
def init(ctx):
global LOGFILE
filename = os.path.abspath(LOGFILE)
try:
os.makedirs(os.path.dirname(os.path.abspath(filename)))
except OSError:
pass
if hasattr(os, 'O_NOINHERIT'):
fd = os.open(LOGFILE, os.O_CREAT | os.O_TRUNC | os.O_WRONLY | os.O_NOINHERIT)
fileobj = os.fdopen(fd, 'w')
else:
fileobj = open(LOGFILE, 'w')
old_stderr = sys.stderr
# sys.stdout has already been replaced, so __stdout__ will be faster
#sys.stdout = log_to_file(sys.stdout, fileobj, filename)
#sys.stderr = log_to_file(sys.stderr, fileobj, filename)
def wrap(stream):
if stream.isatty():
return ansiterm.AnsiTerm(stream)
return stream
sys.stdout = log_to_file(wrap(sys.__stdout__), fileobj, filename)
sys.stderr = log_to_file(wrap(sys.__stderr__), fileobj, filename)
# now mess with the logging module...
for x in Logs.log.handlers:
try:
stream = x.stream
except AttributeError:
pass
else:
if id(stream) == id(old_stderr):
x.stream = sys.stderr
def init(ctx):
global LOGFILE
filename = os.path.abspath(LOGFILE)
try:
os.makedirs(os.path.dirname(os.path.abspath(filename)))
except OSError:
pass
if hasattr(os, 'O_NOINHERIT'):
fd = os.open(LOGFILE, os.O_CREAT | os.O_TRUNC | os.O_WRONLY | os.O_NOINHERIT)
fileobj = os.fdopen(fd, 'w')
else:
fileobj = open(LOGFILE, 'w')
old_stderr = sys.stderr
# sys.stdout has already been replaced, so __stdout__ will be faster
#sys.stdout = log_to_file(sys.stdout, fileobj, filename)
#sys.stderr = log_to_file(sys.stderr, fileobj, filename)
def wrap(stream):
if stream.isatty():
return ansiterm.AnsiTerm(stream)
return stream
sys.stdout = log_to_file(wrap(sys.__stdout__), fileobj, filename)
sys.stderr = log_to_file(wrap(sys.__stderr__), fileobj, filename)
# now mess with the logging module...
for x in Logs.log.handlers:
try:
stream = x.stream
except AttributeError:
pass
else:
if id(stream) == id(old_stderr):
x.stream = sys.stderr
def init(ctx):
global LOGFILE
filename = os.path.abspath(LOGFILE)
try:
os.makedirs(os.path.dirname(os.path.abspath(filename)))
except OSError:
pass
if hasattr(os, 'O_NOINHERIT'):
fd = os.open(LOGFILE, os.O_CREAT | os.O_TRUNC | os.O_WRONLY | os.O_NOINHERIT)
fileobj = os.fdopen(fd, 'w')
else:
fileobj = open(LOGFILE, 'w')
old_stderr = sys.stderr
# sys.stdout has already been replaced, so __stdout__ will be faster
#sys.stdout = log_to_file(sys.stdout, fileobj, filename)
#sys.stderr = log_to_file(sys.stderr, fileobj, filename)
sys.stdout = log_to_file(sys.__stdout__, fileobj, filename)
sys.stderr = log_to_file(sys.__stderr__, fileobj, filename)
# now mess with the logging module...
for x in Logs.log.handlers:
try:
stream = x.stream
except AttributeError:
pass
else:
if id(stream) == id(old_stderr):
x.stream = sys.stderr
def __init__(self, name, mode):
mode = {
"r": os.O_RDONLY,
"w": os.O_WRONLY | os.O_CREAT | os.O_TRUNC,
}[mode]
if hasattr(os, "O_BINARY"):
mode |= os.O_BINARY
self.fd = os.open(name, mode, 0o666)
def __init__(self, name, mode):
mode = {
"r": os.O_RDONLY,
"w": os.O_WRONLY | os.O_CREAT | os.O_TRUNC,
}[mode]
if hasattr(os, "O_BINARY"):
mode |= os.O_BINARY
self.fd = os.open(name, mode, 0o666)
def __init__(self, name, mode):
mode = {
"r": os.O_RDONLY,
"w": os.O_WRONLY | os.O_CREAT | os.O_TRUNC,
}[mode]
if hasattr(os, "O_BINARY"):
mode |= os.O_BINARY
self.fd = os.open(name, mode, 0o666)
def __init__(self, name, mode):
mode = {
"r": os.O_RDONLY,
"w": os.O_WRONLY | os.O_CREAT | os.O_TRUNC,
}[mode]
if hasattr(os, "O_BINARY"):
mode |= os.O_BINARY
self.fd = os.open(name, mode, 0o666)
def __init__(self, name, mode):
mode = {
"r": os.O_RDONLY,
"w": os.O_WRONLY | os.O_CREAT | os.O_TRUNC,
}[mode]
if hasattr(os, "O_BINARY"):
mode |= os.O_BINARY
self.fd = os.open(name, mode, 0o666)
def __init__(self, name, mode):
mode = {
"r": os.O_RDONLY,
"w": os.O_WRONLY | os.O_CREAT | os.O_TRUNC,
}[mode]
if hasattr(os, "O_BINARY"):
mode |= os.O_BINARY
self.fd = os.open(name, mode, 0o666)
def __init__(self, name, mode):
mode = {
"r": os.O_RDONLY,
"w": os.O_WRONLY | os.O_CREAT | os.O_TRUNC,
}[mode]
if hasattr(os, "O_BINARY"):
mode |= os.O_BINARY
self.fd = os.open(name, mode, 0o666)
def save(self):
config_file = RelativePathResolver().absolute("config.json")
try:
# Check if file exists (supports also hidden files)
if os.path.isfile(config_file):
# Use write mode that also works with hidden files
with open(os.open(config_file, os.O_WRONLY | os.O_TRUNC), 'w') as file:
json.dump(self.serialize(), file)
else:
# Simply create a new file
with open(config_file, "w") as file:
json.dump(self.serialize(), file)
except IOError:
pass
def __init__(self, name, mode):
mode = {
"r": os.O_RDONLY,
"w": os.O_WRONLY | os.O_CREAT | os.O_TRUNC,
}[mode]
if hasattr(os, "O_BINARY"):
mode |= os.O_BINARY
self.fd = os.open(name, mode, 0o666)
def __init__(self, server, filename, flags, attrs):
self.server = server
openFlags = 0
if flags & FXF_READ == FXF_READ and flags & FXF_WRITE == 0:
openFlags = os.O_RDONLY
if flags & FXF_WRITE == FXF_WRITE and flags & FXF_READ == 0:
openFlags = os.O_WRONLY
if flags & FXF_WRITE == FXF_WRITE and flags & FXF_READ == FXF_READ:
openFlags = os.O_RDWR
if flags & FXF_APPEND == FXF_APPEND:
openFlags |= os.O_APPEND
if flags & FXF_CREAT == FXF_CREAT:
openFlags |= os.O_CREAT
if flags & FXF_TRUNC == FXF_TRUNC:
openFlags |= os.O_TRUNC
if flags & FXF_EXCL == FXF_EXCL:
openFlags |= os.O_EXCL
if attrs.has_key("permissions"):
mode = attrs["permissions"]
del attrs["permissions"]
else:
mode = 0777
fd = server.avatar._runAsUser(os.open, filename, openFlags, mode)
if attrs:
server.avatar._runAsUser(server._setAttrs, filename, attrs)
self.fd = fd
def __init__(self, name, mode):
mode = {
"r": os.O_RDONLY,
"w": os.O_WRONLY | os.O_CREAT | os.O_TRUNC,
}[mode]
if hasattr(os, "O_BINARY"):
mode |= os.O_BINARY
self.fd = os.open(name, mode, 0o666)
def __init__(self, name, mode):
mode = {
"r": os.O_RDONLY,
"w": os.O_WRONLY | os.O_CREAT | os.O_TRUNC,
}[mode]
if hasattr(os, "O_BINARY"):
mode |= os.O_BINARY
self.fd = os.open(name, mode, 0666)
def set_sequences(self, sequences):
"""Set sequences using the given name-to-key-list dictionary."""
f = open(os.path.join(self._path, '.mh_sequences'), 'r+')
try:
os.close(os.open(f.name, os.O_WRONLY | os.O_TRUNC))
for name, keys in sequences.iteritems():
if len(keys) == 0:
continue
f.write('%s:' % name)
prev = None
completing = False
for key in sorted(set(keys)):
if key - 1 == prev:
if not completing:
completing = True
f.write('-')
elif completing:
completing = False
f.write('%s %s' % (prev, key))
else:
f.write(' %s' % key)
prev = key
if completing:
f.write(str(prev) + '\n')
else:
f.write('\n')
finally:
_sync_close(f)
def __init__(self, name, mode):
mode = {
"r": os.O_RDONLY,
"w": os.O_WRONLY | os.O_CREAT | os.O_TRUNC,
}[mode]
if hasattr(os, "O_BINARY"):
mode |= os.O_BINARY
self.fd = os.open(name, mode, 0o666)
def __init__(self, name, mode):
mode = {
"r": os.O_RDONLY,
"w": os.O_WRONLY | os.O_CREAT | os.O_TRUNC,
}[mode]
if hasattr(os, "O_BINARY"):
mode |= os.O_BINARY
self.fd = os.open(name, mode, 0o666)
def __init__(self, name, mode):
mode = {
"r": os.O_RDONLY,
"w": os.O_WRONLY | os.O_CREAT | os.O_TRUNC,
}[mode]
if hasattr(os, "O_BINARY"):
mode |= os.O_BINARY
self.fd = os.open(name, mode, 0o666)
