On the Unix command line, I tend to use 'file':

file *.zip
applepie.zip:   ZIP archive
keylime.zip:    ZIP archive

[download]

Which is pretty much the same technique (relying on a magic number) as moritz and Bloodnok are advocating.

In reply to Re: How to find out a compressed file inside a script ? by dwm042
in thread How to find out a compressed file inside a script ? by balakrishnan

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