I have a script that needs to be able to operate on either a plain text file or a gzipped version of that file. If the file is not gzipped, the file will be opened as follows: 


open(FOO, $foo) || die("ERROR: Unable to open file $foo for read: $!")
+;

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If the file is gzipped, the file will be opened as follows: 


open(FOO, "zcat $foo |") || die("ERROR: Unable to open gzipped file $f
+oo for read: $!");

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How do I write a check to determine whether the file is gzipped or not? zcat errors out when called on non-gzipped files.

In reply to How to test if a file is gzipped or not by Special_K

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