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On Wed, 26 Sep 2007 10:14:58 +0200, Alexander Skwar wrote: |
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> Back to tar: Why use "tar -j" in scripts, when "bzip2 | tar" |
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> does the same thing? I very much disagree that "tar -j" is |
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> the "better" option here; |
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Either way requires that you first determine the type of compression used |
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before you can decide where to pipe tar's output, if at all. Whereas |
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something like "tar xf somefile" avoids the need to do" file somefile" |
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and parse the output first. |
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> in fact, I'd say that "bzip2 | tar" |
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> is the better option, as it works on a lot more systems than |
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> "tar -j" does. Heck, "tar -j" even does not work on all GNU |
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> tar implementations, as very old GNU tars don't have bzip2 |
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> support at all and -j wasn't always used for bzip2. |
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If you don't know the details of the platform running your script, you |
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should of course stick to POSIX, which tar can do fine. But if your |
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script in running in an environment you control, why not make use of more |
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efficient methods? |
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> > POSIX |
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> > specifies the minimum set of options and features, not the maximum. As |
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> > long as the standards aren't broken, nothing is wrong, and adding new, |
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> > useful and compatible features is one way that standards get |
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> > improved. |
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> |
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> No, it's not. To improve a standard, you make sure that the standard |
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> gets amended and then you implement something. Not the other way around. |
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That's not how evolution works. Things are tried, some (most) fall by the |
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wayside and others are accepted. As long as you don't break the standard |
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with your enhancements, where's the harm in improvement? I know car |
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analogies are tired, but it's like arguing that all cars should be |
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designed to meet the minimum standards required by law, and if the law |
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doesn't stipulate air conditioning, we don't need it - that example is |
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usually true here in the UK :( |
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-- |
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Neil Bothwick |
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The fact that no one understands you doesn't mean you're an artist. |