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On Tue, 26 Nov 2013 01:16:45 +0200 |
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Alan McKinnon <alan.mckinnon@×××××.com> wrote: |
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> You don't do it that way. I understand what you want to do, but your |
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> description makes no sense. |
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> |
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> How you do it is by running two commands on one line, one after the other. |
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> |
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> To copy a file "myfile.txt" to /tmp and also change it's permissions, |
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> use the ";" separator: |
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> |
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> cp myfile.txt /tmp ; chmod 644 /tmp/myfile.txt |
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> |
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> That runs the first command (cp) and then blindly runs the second one. |
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> |
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> |
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> |
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> |
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> Sometimes you want to run the second command only if the first one |
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> succeeds (there's not much point in chmod'ing a file that didn't copy |
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> properly. "&&" does this: |
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> |
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> cp myfile.txt /tmp && chmod 644 /tmp/myfile.txt |
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> |
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> "&&" is boolean logic and a very common programming trick. I won't bore |
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> you with details - it gets complex and we'd have to deal with brash |
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> crazies like why true and false is the wrong way round the the rest of |
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> the world, but just know it this way: |
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> |
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> the second command (chmod) will only run if the first (cp) succeeded. If |
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> it failed, the chmod will not be be tried. |
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> |
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> Note that "&&" is definitely not the same thing as just one "&" - that |
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> is something completely different. Bash is full of such stuff, it's all |
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> done deliberately to mess with your head :-) |
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> |
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Thanks for the prompt reply and free lesson, I appreciate it:-) |
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Yes...this is exactly what I was looking for. |
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-- |
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edwardunix@××××.com <edwardunix@××××.com> |
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