Bash，数组和空白导致奇怪的行为

Question

Problem: Writing a bash script, i'm trying to import a list of products that are inside a csv file into an array:

#!/bin/bash
    PRODUCTS=(`csvprintf -f "/home/test/data/input.csv" -x | grep "col2" | sed 's/<col2>//g' | sed 's/<\/col2>//g' | sed -n '1!p' | sed  '$ d' | sed 's/    //g'`)

    echo ${PRODUCTS[@]}

In the interactive shell, the result/output looks perfect as following:

burger
special fries
juice - 300ml

When i use exactly the same commands in bash script, even debugging with bash -x script.sh , in the part of echo ${PRODUCTS[@]} , the result of array is all files names located at /home/test/data/ and:

burger
special
fries
juice
- 
300ml

The array is taking directory list AND messed up newlines. This don't happen in interactive shell (single command line). Anyone know how to fix that?

Answer 1

Looking at the docs for csvprintf , you're converting the csv into XML and then parsing it with regular expressions. This is generally a very bad idea.

You might want to install csvkit then you can do

csvcut -c prod input.csv | sed 1d

Or you could use a language that comes with a CSV parser module. For example, ruby

ruby -rcsv -e 'CSV.read("input.csv", :headers=>true).each {|row| puts row["prod"]}'

Whichever method you use, read the results into a bash array with this construct

mapfile -t products < <(command to extract the product data)

Then, to print the array elements:

for prod in "${products[@]}"; do echo "$prod"; done
# or
printf "%s\n" "${products[@]}"

The quotes around the array expansion are critical. If missing, you'll see one word per line.

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Tip: don't use ALLCAPS variable names in the shell: leave those for the shell. One day you'll write PATH=something and then wonder why your script is broken.