wade@V1088:~$ cat b.sh#!/bin/bash dir=`pwd` dir=$dir'/' for f in `ls *.png` do echo $dir$f done 看每一行代码的执行: wade@V1088:~$ bash -x b.sh ++ pwd + dir=/home/wade + dir=/home/wade/ ++ ls chrome_1407299385726.png chrome_1427299385726.png + for f in '`ls *.…