bash - 在旧版本的 Bash 上需要替代 readarray/mapfile 的脚本

Question

脚本是:

#!/bin/bash

# Dynamic Menu Function
createmenu () {
    select selected_option; do # in "$@" is the default
        if [ 1 -le "$REPLY" ] && [ "$REPLY" -le $(($#)) ]; then
            break;
        else
            echo "Please make a vaild selection (1-$#)."
        fi
    done
}

declare -a drives=();
# Load Menu by Line of Returned Command
mapfile -t drives < <(lsblk --nodeps -o name,serial,size | grep "sd");
# Display Menu and Prompt for Input
echo "Available Drives (Please select one):";
createmenu "${drives[@]}"
# Split Selected Option into Array and Display
drive=($(echo "${selected_option}"));
echo "Drive Id: ${drive[0]}";
echo "Serial Number: ${drive[1]}";

旧系统没有mapfile或 readarray所以我需要将该行转换为可以读取 lsblk 的每一行的替代方法输出到数组中。

创建数组的行是:

mapfile -t drives < <(lsblk --nodeps -o name,serial,size | grep "sd");

Answer 1

您可以遍历您的输入并附加到数组:

$ while IFS= read -r line; do arr+=("$line"); done < <(printf '%d\n' {0..5})
$ declare -p arr
declare -a arr='([0]="0" [1]="1" [2]="2" [3]="3" [4]="4" [5]="5")'

或者，对于您的具体情况:

while IFS= read -r line; do
    drives+=("$line")
done < <(lsblk --nodeps -o name,serial,size | grep "sd")

参见 BashFAQ/001对于为什么 IFS= read -r 是一个好主意的一个很好的解释:它确保保留空格并且不解释反斜杠序列。