Description:
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I've noticed a really confusing fact.
MD5_file and shell md5sum gives different checksums in some cases.

I've written a complete file integrity check in php.
O was using md5sum from shell to calcullate md5 checksums. After switching to md5_file i've got allerts in some files.
So I made some test, and found, that in some cases md5sum and md5_file gives different output !!!
on my /usr/lib directory I've got 6 differences.


Reproduce code:
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shell_exec("/usr/bin/md5sum $currentfile");
md5_file($currentfile);