Quick answer: see the -T and -B file tests. Read the documentation (quick quote in one of my previous posts: Re: How reliable is -T as a test for ASCII files?) to see how they work.

"before opening" is really "before explicit opening by you". Any tests need to open the file to examine its contents.

Update: Roy Johnson above is a quicker typist than me :)

In reply to Re: Some binary wisdom needed by calin
in thread Some binary wisdom needed by vivapl

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