如何调试shell脚本？

$ cat checkdebug2.sh

#!/bin/bash

cd /var/log/

for i in "*.log"; do

 du -sh $i

done

# sh -xv checkdebug2.sh

#!/bin/bash

cd /var/log/

+ cd /var/log/

for i in "*.log"; do

 du -sh $i

done

+ for i in '"*.log"'

+ du -sh boot.log mysqld.log post111.log post1121.log yum.log

0       boot.log

32K     mysqld.log

0       post111.log

0       post1121.log

4.0K    yum.log