1. cat -n filename
2.nl filename
3. grep -n ".* " filename
4.awk '{print NR,$0}' filename
5. less -N filename (按q退出)
6.sed '=' filename | sed 'N;s#\n# #g'
7. vim filename :set nu
1、cat -n aaa.txt
2、nl aaa.txt #===>不显示空行
3、grep -n ".*" aaa.txt
4、awk '{print NR,$0}' 123.txt
5、less -N 123.txt
6、sed '=' 123.txt |sed 'N;s#\n# #g'
7、vim 123.txt ：set nu
