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On Nov 8, 2011 1:01 PM, "Pandu Poluan" <pandu@××××××.info> wrote: |
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> |
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> |
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> On Nov 8, 2011 9:02 AM, "Claudio Roberto França Pereira" < |
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spideybr@×××××.com> wrote: |
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> > |
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> > What about [[? I've seen scripts using [[ instead of only one [. Whats |
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the point/difference? |
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> |
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> AFAIK [[ was originally a bash-specific built-in command that provides |
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more functionality than /bin/[, but can still use /bin/['s convoluted |
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syntax. |
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> |
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> The two converged quickly, though. IIRC [ is now also a bash built-in, |
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which still maintains compatibility with /bin/[ |
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> |
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> An example: |
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> [ $VAR ] will produce an error if VAR is empty or unset, but [[ $VAR ]] |
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won't. |
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> (for the former, you have to put double quotes around, e.g., [ "$VAR"] ) |
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> |
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Uh... of course there should be a space between the second double-quote and |
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the closing bracket. |
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Rgds, |
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