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On Friday 8 May 2009, 16:51, Alan McKinnon wrote: |
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> > > except that STDERR is combined with STDOUT and sent to /dev/null |
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> > > so the script will never get it, the if is always true and the |
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> > > entire check is redundant. Better would be |
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> > > |
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> > > if echo hello|grep --color=auto l >/dev/null ; then |
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> > |
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> > That will output an uncaptured error message if --color is not |
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> > supported. |
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> |
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> which is the desired effect. It causes the if to be false and the grep |
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> options are not enabled (as they are not supported) |
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It's not the fact that the error message is left free to show on screen |
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that makes the exit status true or false. |
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If the file is sourced from a non-interactive environment, you don't want |
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anything printed (and probably, in this case, neither if it's an |
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interactive session). Capturing stderr does not change the exit status |
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of the pipeline. |
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