You could use file(1) magic to check if a file is indeed a compressed file before trying to uncompress.

... but you should remember that this creates a TOCTTOU vulnerability. Also, magic checks check only for magic numbers, not for validity.

Alexander

--
Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)

In reply to Re^2: How do you get IO::Uncompress::Gunzip to error if the input file isn't a GZ file? by afoken
in thread How do you get IO::Uncompress::Gunzip to error if the input file isn't a GZ file? by sectokia

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