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Comment by Freak_NL | Hacker News Reader

I guess a lot of people are or were used to:

  tar -xzf file.tar.gz

To be honest, I only started doing -xf a year ago. I was used to -xjf and -xzf.

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tar flags must be a prime example of cargo culting. Hands up everyone who's done or seen someone do

  tar -xzvf file.tgz > /dev/null

never seen that in my life until now - what does it do? Just unzip the file to dev/null? What's the purpose? Does the verbose flag show you what's inside but the dev/null means it's not written to disk while unzipping?

Actually, the files are decompressed to the current directory, it's the just output of the verbose flag that goes to /dev/null. Which makes is even more senseless.

Exactly. I've seen people who always do `tar xzvf` and have no idea removing the `v` is the correct way to make it not print the name of every file in the archive.

I use the -v switch since I want to see what I decompress, however I didn't knew that I could supress the z switch.

Isn't it better though to omit the -v switch and do `ls *` and/or `tree` afterwards? That gives you the same information but structured so it's much easier to understand.

The advantage of -v is that you can see what is being extracted as it happens. This is useful if you have a tarball with thousands of small files, as otherwise it's hard to tell whether tar has got stuck or there are just a lot of files.

You didn't use to be able to suppress the 'z' switch. You had to specify 'z' or 'j' depending on whether you wanted gzip or bzip2 decompression. It's a somewhat recent (sometime in the last 15 years, I think) change to "tar" to make it just detect the compression algorithm.

I don't understand why you'd do that. tar does not compress to stdout.

Redirecting stdout is to cancel the -v flag (verbose, lists every file extracted).

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