Copy file preserving directory structure in Linux

Use cp --parents /d1/d2/d3/f4 /e1/e2/e3 to get the copy /e1/e2/e3/d1/d2/d3/f4.

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Grepping specific files recursively

To search the pattern PAT in all csv and csv.bak files in the directory DIR and its subdirectories, do

grep --include=*.csv* -ER "PAT" DIR

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