24 lines
1.4 KiB
Text
24 lines
1.4 KiB
Text
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Normally, in a pipeline, when you need to edit some phase of the data
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stream, you use a standard tool such as sed, grep, or awk to alter,
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filter, or otherwise manipulate the stream. One potential problem with
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this approach is that the manipulations have to be very well thought out
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in advance. Another is that the manipulations will probably need to be
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applied uniformly. And third, the data must be very well understood in
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advance. Not all situations and data easily conform to these
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constraints.
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Alternatively, when the changes needed for the data are more than
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trivial, or perhaps you just don't feel like expending the mental energy
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needed to work out all the expressions in advance, a typical approach
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might be to run some process or pipeline, dump output to a file, edit
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the file with vi, pico, or emacs, then push the data along to the next
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phase by using the file as input to some additional process or pipeline.
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The catch here - other than the sheer awkwardness of this process - is
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that you have to remember to come back later and clean up all of those
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little and not-so-little "temporary" files.
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So, wouldn't you just like to be able to tap in an edit session at any
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arbitrary point in the pipeline, do your magic on the data, then have it
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automagically continue on its merry way? The vip program provides this
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functionality, and operates syntactically just like any other filter.
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