linux – Bash 19个字符没有任何理由消失

我试图制作一个批处理脚本来压缩我的音频文件,我面临一个非常奇怪的问题.

这是我的代码：

#!/bin/bash

qscale=$1
input=$2
output=$3
inputSize=$((${#input}+1))

find "$input" -type f -name "*.flac" -print0 | while read -d $'\0' a
do
    path=${a:inputSize}
    echo "Working on $path"
#    ffmpeg -i "$a" -qscale:a $qscale "$output/${path[@]/%flac/mp3}" &>/dev/null
done

这是一个结果示例：

Working on 09 - Groove #2 (instrumental studio outtake).flac
Working on 07 - Blues for Allah Sand Castles and Glass Camels Unusual Occurrences in the Desert.flac
Working on 12 - Proto 18 Proper (instrumental studio outtake).flac
Working on 04 - The Music Never Stopped.flac
Working on 13 - Hollywood Cantana (studio outtake).flac
...

如果我取消注释ffmpeg行,这是同一文件夹的结果：

Working on 09 - Groove #2 (instrumental studio outtake).flac
Working on h Sand Castles and Glass Camels Unusual Occurrences in the Desert.flac
Working on 12 - Proto 18 Proper (instrumental studio outtake).flac
Working on r Stopped.flac
Working on 13 - Hollywood Cantana (studio outtake).flac
...

两个文件中的一个文件错过了第19个第一个字符！而且我不知道为什么.

解决方法:

取消注释ffmpeg行并在其上运行shellcheck报告：

Line 12:
    ffmpeg -i "$a" -qscale:a $qscale "$output/${path[@]/%flac/mp3}" &>/dev/null
    ^-- SC2095: Add < /dev/null to prevent ffmpeg from swallowing stdin.

再试一次

ffmpeg -i "$a" -qscale:a $qscale "$output/${path[@]/%flac/mp3}" &>/dev/null < /dev/null

ffmpeg,以及ssh和mplayer,因读取循环时窃取stdin而臭名昭着.