数组 – 在循环中分配给数组索引的麻烦

我需要运行一个外部命令,其中输出的每一行都将存储在数组索引中.

这个简化的例子看起来是正确地在循环中设置数组但是在循环完成后这些数组赋值消失了？好像循环被完全视为外壳？

junk.txt

this is a
test to see
if this works ok

testa.sh

#!/bin/bash

declare -i i=0
declare -a array

echo "Simple Test:"
array[0]="hello"
echo "array[0] = ${array[0]}"

echo -e "nLoop through junk.txt:"
cat junk.txt | while read line
do
    array[i]="$line"
    echo "array[$i] = ${array[i]}"
    let i++
done

echo -e "nResults:"
echo "       array[0] = ${array[0]}"
echo " Total in array = ${#array[*]}"
echo "The whole array:"
echo ${array[@]}

产量

Simple Test:
array[0] = hello

Loop through junk.txt:
array[0] = this is a
array[1] = test to see
array[2] = if this works ok

Results:
      array[0] = hello
Total in array = 1
The whole array:
hello

因此,在循环中,我们分配array [i]并且echo验证它.
但是在循环之后我回到了包含“hello”的数组[0]而没有其他元素.

bash 3,4和不同平台的结果相同.