How to compare two saved files with the filename of same url?

I'm saving many text files. Filenames are urls. File has whole html of webpage from url. All text files are saved in one folder.

My problem: I need to compare two files of same url, but how?

• filenames of same webpage 开发者_JAVA百科are the same, I cant save 2 files with the same name.
• add version of url is stupid because I cant add it into my webapplication.

Please help me how can I save two files of same webpage and compare their content.

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Are you checking this URL at two different times? I would imagine so, because if you checked it twice in a row then there would be no changes. So if you are checking at different times, why not place each one into a subfolder named after the date:

/etc/2011-01-02 2255/web-page-url.text
/etc/2011-02-02 2255/web-page-url.text

Then you don't have top worry about the two files having the same name.