You can check the first 2 bytes of the file. If they are PK, then you have a .zip file.

Or, to be slightly more accurate, if they are not PK you know that you don't have a .zip file :-)

There is nothing to stop a non-zip file starting with PK.

If you want to be sure use Archive::Zip to attempt to extract the file or check the file's CRCs.

In reply to Re: Re: testing for a zip file by adrianh
in thread testing for a zip file by Anonymous Monk

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