Shell脚本实现监测文件变化的示例详解

#!/bin/bash
# ------------------------------------------
# Filename    : fileTracer.sh
# Version     : 1.1
# Date        : 2022-5-22 00:52:23
# Author      : 农民工老王@CSDN
# Email       : scwja@qq.com
# Website     : https://blog.csdn.net/monarch91
# Description : 用于追踪文件变化的脚本
# ------------------------------------------

time=$1
sleepNum=$2
filePath=$3
fileName=`basename ${filePath}`
whileNum=$(echo "scale=0;${time}*60/${sleepNum}"|bc)
flag=0
historyDir=./fileHistory
timeStr=""

detection_log() {
  timeStr=$(date "+%H:%M:%S.%N")
  timeStr=${timeStr:0:12}
  echo -e "\033[35m${timeStr}\033[0m \033[36m[DEBUG]\033[0m :$1"
}

existNotice=0
deleteNotice=0
md5StrLast=""
mkdir -p $historyDir
while [ $flag  -lt $whileNum ]; do
  if [ -f "${filePath}"  ]; then
    if [ $existNotice -eq  1 ] || [ $flag -eq 0 ] ; then
      if [ $flag -eq 0 ]; then
        detection_log "文件已存在。"
      else
        detection_log "文件被创建。"
      fi
      md5StrLast=`md5sum ${filePath} | awk '{ print $1 }'`
      cp -fr ${filePath} ${historyDir}/${timeStr}_${fileName}
    else
      md5StrNow=`md5sum ${filePath} | awk '{ print $1 }'` >/dev/null 2>&1
      if [ "lw${md5StrNow}" != "lw" ] && [ "lw${md5StrNow}" != "lw${md5StrLast}" ]; then
         detection_log "文件被修改。"
         cp -fr ${filePath} ${historyDir}/${timeStr}_${fileName}
         md5StrLast=${md5StrNow}
      fi
    fi
    existNotice=0
    deleteNotice=1
  else
    if [ $flag -eq 0 ]; then
        detection_log "文件未创建。"
    elif [ $deleteNotice -eq 1 ]; then
        detection_log "文件被删除。"
    fi
    deleteNotice=0
    existNotice=1
  fi

  flag=$((flag+1))
  sleep ${sleepNum}
done