在 Python 中结束睡眠循环

Question

我写了一个 python 脚本，其中包含一个睡眠循环来监视日志文件，等待新行处理：

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

我想对此进行修改，以便在没有换行的情况下花费超过 1 小时时，结束循环并继续执行脚本。到目前为止还没有成功。

Answer 1

将 while 1（顺便说一句，实际上应该写成 while True）更改为检查循环中花费了多长时间的条件。

类似于：

file = ...
now = time.time()

while time.time() - now < 1 * 60 * 60:

Answer 2

试试这段代码。

file = open('logFile.log', 'r')

while True:
    timeWait = 60*60 # Change the Value to something less to check whether the code works properly or not.
    where = file.tell()
    line = file.readline()
    if not line:
        time.sleep(1)
        timeWait = timeWait - 1
        file.seek(where)
        if timeWait == 0:
            break
    else:
        print line

Answer 3

您可以更改 while 以检查 1 小时时段并重置 startTime，如下所示：

file = open('logFile.log', 'r')
startTime = time.time()
while (time.time()-startTime) >= 3600:
    where = file.tell()
    line = file.readline()
    if not line:
        time.sleep(1)
        file.seek(where)
    else:
        startTime = time.time() #record the last time output was available
        print line, # already has newline

Answer 4

只保留一个计数器：

count = 0
file = open('logFile.log', 'r')
while 1:
    where = file.tell()
    line = file.readline()
    if not line:
        count = count + 1
        if count >= 3600:
          break
        time.sleep(1)
        file.seek(where)
    else:
        print line, # already has newline
        count = 0
# if you get here an hour without any newlines has passed

Answer 5

这个问题的一个重点是1小时没有换行CONTINUOUSLY，所以确实有必要在换行打印后重置时间计数器。

count = 0
one_hour = 60 * 60
file = open('logFile.log', 'r')
while 1:
    where = file.tell()
    line = file.readline()
    if not line:
        count = count + 1
        if count >= one_hour:
          break
        time.sleep(1)
        file.seek(where)
    else:
        print line
        count = 0   # Here needs to reset the time couter!

在 Python 中结束睡眠循环

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