在bash中循环遍历数组

Question

I am currently attempting to create a bash script that will check inside of each users /Library/Mail folder to see if a folder named V2 exists. The script should create an array with each item in the array being a user and then iterate through each of these users checking their home folder for the above captioned contents. This is what I have so far:

#!/bin/bash

cd /Users

array=($(ls))

for i in ${array[@]}
do

if [ -d /$i/Library/Mail/V2 ]

then
    echo "$i mail has been upgraded."
else 
    echo "$i FAIL"

fi

done

Answer 1

Populating your array from the output of ls is going to make for serious problems when you have a username with spaces. Use a glob expression instead. Also, using [ -d $i/... ] will similarly break on names with spaces -- either use [[ -d $i/... ]] (the [[ ]] construct has its own syntax rules and doesn't require quoting) or [ -d "$i/..." ] (with the quotes).

Similarly, you need to double-quote "${array[@]}" to avoid string-splitting from splitting names with spaces in two, as follows:

cd /Users
array=(*)
for i in "${array[@]}"; do
  if [[ -d $i/Library/Mail/V2 ]]; then
    echo "$i mail has been upgraded."
  else 
    echo "$i FAIL"
  fi
done

That said, you don't really need an array here at all:

for i in *; do
  ...check for $i/Library/Mail/V2...
done