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phpdestroyfile-put-contents

Can PHP save to a file during __destruct()

I would like to save some info to a file on my server using the __destruct() function in one of my classes.

However, every time I try to use file_put_contents(...) inside __destruct(), I get this error:

Warning: file_put_contents(HTMLcache.txt): failed to open stream: Permission denied in /Applications/MAMP/htdocs/time/HJ_Tag.php on line 141

file_put_contents(...) works just fine in other parts on my code, where it is called on the exact same file. What might it be causing this error during __destruct(), and how can I fix it?

Solution

  • I think you mean __destruct() instead of __destroy(), so I edited your post.

    Can PHP save to a file during __destruct()

    Yes, it can. However, when you use relative filename with file_put_contents() like this:

    file_put_contents('hello.txt', 'hello world');

    The file may actually be created somewhere you're not expecting and you may not have write permission there, which explains the error message.

    In my case, it was created in C:\Users\Rei\AppData\Local\VirtualStore. Which is odd because I never specified that directory. I had to search my entire harddrive to find it.

    To prevent that, always use absolute filename. For instance, add __DIR__ before the filename.

    file_put_contents(__DIR__ . 'hello.txt', 'hello world');

    And make sure you have write permission.