在哪里更改这个Python代码段以将临时文件保存在tmpfolder中?

2024-09-28 01:25:55 发布

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这是一个实现文件锁的代码示例,因此应用程序只能打开一个实例。它目前可以工作,但将锁文件保存在主文件夹(Ubuntu)中。如果应用程序崩溃,锁文件不会被删除,这是不好的。。。。在

我不太容易看到应该在哪里更改代码以将其保存在c:/tmp文件夹中?在

#!/usr/bin/python
# -*- coding: utf-8 -*-


#implements a lockfile if program already is open
import os
import socket
from fcntl import flock

class flock(object):
    '''Class to handle creating and removing (pid) lockfiles'''

    # custom exceptions
    class FileLockAcquisitionError(Exception): pass
    class FileLockReleaseError(Exception): pass

    # convenience callables for formatting
    addr = lambda self: '%d@%s' % (self.pid, self.host)
    fddr = lambda self: '<%s %s>' % (self.path, self.addr())
    pddr = lambda self, lock: '<%s %s@%s>' %\
                              (self.path, lock['pid'], lock['host'])

    def __init__(self, path, debug=None):
        self.pid   = os.getpid()
        self.host  = socket.gethostname()
        self.path  = path
        self.debug = debug # set this to get status messages

    def acquire(self):
        '''Acquire a lock, returning self if successful, False otherwise'''
        if self.islocked():
            if self.debug:
                lock = self._readlock()
                print 'Previous lock detected: %s' % self.pddr(lock)
            return False
        try:
            fh = open(self.path, 'w')
            fh.write(self.addr())
            fh.close()
            if self.debug:
                print 'Acquired lock: %s' % self.fddr()
        except:
            if os.path.isfile(self.path):
                try:
                    os.unlink(self.path)
                except:
                    pass
            raise (self.FileLockAcquisitionError,
                   'Error acquiring lock: %s' % self.fddr())
        return self

    def release(self):
        '''Release lock, returning self'''
        if self.ownlock():
            try:
                os.unlink(self.path)
                if self.debug:
                    print 'Released lock: %s' % self.fddr()
            except:
                raise (self.FileLockReleaseError,
                       'Error releasing lock: %s' % self.fddr())
        return self

    def _readlock(self):
        '''Internal method to read lock info'''
        try:
            lock = {}
            fh   = open(self.path)
            data = fh.read().rstrip().split('@')
            fh.close()
            lock['pid'], lock['host'] = data
            return lock
        except:
            return {'pid': 8**10, 'host': ''}

    def islocked(self):
        '''Check if we already have a lock'''
        try:
            lock = self._readlock()
            os.kill(int(lock['pid']), 0)
            return (lock['host'] == self.host)
        except:
            return False

    def ownlock(self):
        '''Check if we own the lock'''
        lock = self._readlock()
        return (self.fddr() == self.pddr(lock))

    def __del__(self):
        '''Magic method to clean up lock when program exits'''
        self.release()

#now testing to see if file is locked = other instance of this program is running already

lock = flock('tmp.lock', True).acquire()
if lock:
    print 'doing stuff'
else:
    print 'locked!'
    exit()


#end of lockfile

Tags: topathdebugselflockhostreturnif
2条回答

在脚本末尾:

lock = flock('tmp.lock', True).acquire()

'tmp.lock'是当前目录中文件的路径。将其更改为您需要的路径,即'c:/tmp-folder/tmp.lock'。在

^{pr2}$

然而,正如@g19狂热者所说:你是在Windows('c:/…')还是Linux(Ubuntu)系统上?在

使用tempfile

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