Description:
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Calling fpassthru() or readfile() on a file returns a truncated file, using:

echo file_get_contents(); and it works fine.

I'm assuming its a binary issue, I know it has problems with pdf documents.

Reproduce code:
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readfile($filepath); // Returns unreadable pdf file


Expected result:
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Uncorrupted file returned to browser

Actual result:
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Corrupted file returned to browser