看看我对类似问题的回答。您可以在Python中尝试相同的循环。本页建议:

import time

while 1:
    where = file.tell()
    line = file.readline()
    if not line:
        time.sleep(1)
        file.seek(where)
    else:
        print line, # already has newline

还可以使用Python查看文件中的问题tail()。

相关@4Oh4解决方案一个流畅的更改文件列表观看;

import os
import sys
import time

class Watcher(object):
    running = True
    refresh_delay_secs = 1

    # Constructor
    def __init__(self, watch_files, call_func_on_change=None, *args, **kwargs):
        self._cached_stamp = 0
        self._cached_stamp_files = {}
        self.filenames = watch_files
        self.call_func_on_change = call_func_on_change
        self.args = args
        self.kwargs = kwargs

    # Look for changes
    def look(self):
        for file in self.filenames:
            stamp = os.stat(file).st_mtime
            if not file in self._cached_stamp_files:
                self._cached_stamp_files[file] = 0
            if stamp != self._cached_stamp_files[file]:
                self._cached_stamp_files[file] = stamp
                # File has changed, so do something...
                file_to_read = open(file, 'r')
                value = file_to_read.read()
                print("value from file", value)
                file_to_read.seek(0)
                if self.call_func_on_change is not None:
                    self.call_func_on_change(*self.args, **self.kwargs)

    # Keep watching in a loop
    def watch(self):
        while self.running:
            try:
                # Look for changes
                time.sleep(self.refresh_delay_secs)
                self.look()
            except KeyboardInterrupt:
                print('\nDone')
                break
            except FileNotFoundError:
                # Action on file not found
                pass
            except Exception as e:
                print(e)
                print('Unhandled error: %s' % sys.exc_info()[0])

# Call this function each time a change happens
def custom_action(text):
    print(text)
    # pass

watch_files = ['/Users/mexekanez/my_file.txt', '/Users/mexekanez/my_file1.txt']

# watcher = Watcher(watch_file)  # simple



if __name__ == "__main__":
    watcher = Watcher(watch_files, custom_action, text='yes, changed')  # also call custom action function
    watcher.watch()  # start the watch going

因为没有人提到它，所以我要把它放在那里:在标准库中有一个名为filecmp的Python模块，它有这个cmp()函数来比较两个文件。

只是要确保你没有使用from filecmp import cmp来掩盖Python 2.x中内置的cmp()函数。这在Python 3中是可以的。X，因为不再有这样的内置cmp()函数了。

不管怎样，它的用法是这样的:

import filecmp
filecmp.cmp(path_to_file_1, path_to_file_2, shallow=True)

参数shallow默认为True。如果参数的值为True，则只比较文件的元数据;但是，如果参数的值为False，则比较文件的内容。

也许这个信息对某人有用。

在对蒂姆·戈尔登的剧本进行了一些修改后，我有了以下似乎工作得相当不错的内容:

import os

import win32file
import win32con

path_to_watch = "." # look at the current directory
file_to_watch = "test.txt" # look for changes to a file called test.txt

def ProcessNewData( newData ):
    print "Text added: %s"%newData

# Set up the bits we'll need for output
ACTIONS = {
  1 : "Created",
  2 : "Deleted",
  3 : "Updated",
  4 : "Renamed from something",
  5 : "Renamed to something"
}
FILE_LIST_DIRECTORY = 0x0001
hDir = win32file.CreateFile (
  path_to_watch,
  FILE_LIST_DIRECTORY,
  win32con.FILE_SHARE_READ | win32con.FILE_SHARE_WRITE,
  None,
  win32con.OPEN_EXISTING,
  win32con.FILE_FLAG_BACKUP_SEMANTICS,
  None
)

# Open the file we're interested in
a = open(file_to_watch, "r")

# Throw away any exising log data
a.read()

# Wait for new data and call ProcessNewData for each new chunk that's written
while 1:
  # Wait for a change to occur
  results = win32file.ReadDirectoryChangesW (
    hDir,
    1024,
    False,
    win32con.FILE_NOTIFY_CHANGE_LAST_WRITE,
    None,
    None
  )

  # For each change, check to see if it's updating the file we're interested in
  for action, file in results:
    full_filename = os.path.join (path_to_watch, file)
    #print file, ACTIONS.get (action, "Unknown")
    if file == file_to_watch:
        newText = a.read()
        if newText != "":
            ProcessNewData( newText )

它可能需要进行更多的错误检查，但对于简单地观察日志文件并在将其输出到屏幕之前对其进行一些处理，这样做效果很好。

谢谢大家的投入-很棒的东西!

这是对Tim Goldan脚本的另一种修改，它运行在unix类型上，并通过使用dict (file=>time)为文件修改添加了一个简单的监控器。

用法:whatvername .py path_to_dir_to_watch

#!/usr/bin/env python

import os, sys, time

def files_to_timestamp(path):
    files = [os.path.join(path, f) for f in os.listdir(path)]
    return dict ([(f, os.path.getmtime(f)) for f in files])

if __name__ == "__main__":

    path_to_watch = sys.argv[1]
    print('Watching {}..'.format(path_to_watch))

    before = files_to_timestamp(path_to_watch)

    while 1:
        time.sleep (2)
        after = files_to_timestamp(path_to_watch)

        added = [f for f in after.keys() if not f in before.keys()]
        removed = [f for f in before.keys() if not f in after.keys()]
        modified = []

        for f in before.keys():
            if not f in removed:
                if os.path.getmtime(f) != before.get(f):
                    modified.append(f)

        if added: print('Added: {}'.format(', '.join(added)))
        if removed: print('Removed: {}'.format(', '.join(removed)))
        if modified: print('Modified: {}'.format(', '.join(modified)))

        before = after

如果轮询对您来说足够好，我只观察“修改的时间”文件统计是否发生变化。阅读方法:

os.stat(filename).st_mtime

(还要注意，Windows本机更改事件解决方案并不在所有情况下都有效，例如在网络驱动器上。)

import os

class Monkey(object):
    def __init__(self):
        self._cached_stamp = 0
        self.filename = '/path/to/file'

    def ook(self):
        stamp = os.stat(self.filename).st_mtime
        if stamp != self._cached_stamp:
            self._cached_stamp = stamp
            # File has changed, so do something...