Bash - Simple script to convert tab separated files to CSV, e.g. DNS Zone files

tsv_to_csv.sh

#!/usr/bin/env bash
# Simple script to convert tab separated files to CSV
# E.g. DNS Zone files

if [ "$1" != "" ]; then
# File name might contain spaces
  IFS=$'\n'
  ZONE_FILES=("$1")

else ZONE_FILES=(
  acme.co.uk.zonefile
  example.com.zonefile
)
fi

for INPUT in "${ZONE_FILES[@]}"; do
  echo "Processing: $INPUT"
  grep -E '\t' "$INPUT" | sed 's/\t/,/g' > "$INPUT.csv"
  echo "    Output: $INPUT.csv"
  echo
done