openTempFile 的原子性
我有以下功能：
safeWrite :: Text -> IO ()
safeWrite c = bracket (openTempFile "/tmp" "list.tmp")
(\(path, h) -> hClose h
>> copyFile path dataFile
>> removeFile path)
(\(_, h) -> TI.hPutStr h c)
我的印象是这样很安全，如果任何时候出现错误都不会发生复制，并且原始文件仍然可以使用。然而就在昨天，我得到了一个空文件，我不知道去哪里查看它。该程序已经运行良好一个多月了，没有出现任何问题，这说明了一些我没有想到的极端情况。
该方法是否保证原子性，这意味着错误在其他地方，或者如果不能，为什么不呢？我应该怎么做才能保证原子性？
I have the following function:
safeWrite :: Text -> IO ()
safeWrite c = bracket (openTempFile "/tmp" "list.tmp")
(\(path, h) -> hClose h
>> copyFile path dataFile
>> removeFile path)
(\(_, h) -> TI.hPutStr h c)
I was under the impression that this would safe, no copying would happen if there were errors during any moment, and the original file would still be usable. However just yesterday I ended up with an empty file, and I have no idea where to go look at it. The program had been running well for over a month without any hiccups which points so some corner case I didn't think of.
Does the method guarantee atomicity, meaning the error is somewhere else, or if not, why not? What should I do to guarantee atomicity?
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对于 Haskell 异常，您对
mkTemp的定义是原子的。如果出现异常，它将打印一条有关失败的消息（将文件保留在那里）。您可以做更多的清理工作，可以选择在出现异常时删除文件，或者简单地使用提供的（原子）
mkTemp函数：openTempFile：http://hackage.haskell .org/packages/archive/base/4.3.1.0/doc/html/System-IO.html#g:22或使用 posix 层：
Your definition of
mkTempis atomic with respect to Haskell exceptions. If there is an exception it will print a message about the failure (leaving the file there).You can do a bit more to clean up, by optionally removing the file if there is an exception, or simply using the provided (atomic)
mkTempfunction:openTempFile: http://hackage.haskell.org/packages/archive/base/4.3.1.0/doc/html/System-IO.html#g:22or using the posix layer: