Shell脚本：倒数计数的屏显小程序



一个小程序献给Shell Script的初学者玩儿~，或许它能激起你学习的兴趣

#!/bin/bash
BOOT_DELAY_COUNT=5

echo -n "APP will run in seconds:  "
while [ ${BOOT_DELAY_COUNT} -ge 0 ]
do
 echo -ne "\b${BOOT_DELAY_COUNT}"
 read -t 1 -n 1
 if [ $? -eq 0 ]; then
  echo -ne "\b \nCancel APP run!\n"
  exit 0
 fi
 
 BOOT_DELAY_COUNT=`expr ${BOOT_DELAY_COUNT} - 1`
done
echo ""
exit 0

### 复制下面的脚本，保存到文件 backcount.sh中即可执行。
1、若没有执行权限，通过 chmod 命令添加；
[root@HLZ home]# ./backcount.sh
-bash: ./backcount.sh: Permission denied
[root@HLZ home]# chmod a+x backcount.sh

2、若文件 backcount.sh在windows下编辑，请确保语系正确，可在Linux上通过 dos2unix 命令转换；
[root@HLZ home]# ./backcount.sh
-bash: ./backcount.sh: /bin/bash^M: bad interpreter: No such file or directory
[root@HLZ home]# dos2unix backcount.sh
dos2unix: converting file backcount.sh to UNIX format ...