- grep love 1.txt
- /^love/
- /love$/
- /l.ve/
- /lo*ve/
- /Llove/
- /lovea-z/
- /love\^a-zA-Z0-9
- /.*/
- /^$/
- /^A-Z..$"/
- /^A-Za-z*30-5/
- /a-z*\."/
- /^*A-Za-za-z$"/
- /^*A-Za-z*\^,A-Za-z*$/
- /\<fourth\>/
- /\<f.*th\> /
- /5{2}2{3}\./
- /^\\t*$/
- /^#/
- /^\\t*#/
- :1,$ s/\(Ooccur\)ence/\1rence/
- :1,$ s /\(square\) and \(fair\)/\2 and \1/
cs
[root@localhost ~]# grep "^$" 1.txt
[root@localhost ~]# grep ".*" 1.txt
#qian
#yoa
#huang
kai
kong
cai
[root@localhost ~]# grep "^$" 1.txt
[root@localhost ~]# grep "[A-Z]..$" 1.txt
[root@localhost ~]# grep "[^A-Z]..$" 1.txt
#qian
#yoa
#huang
kai
kong
cai
duo
[root@localhost ~]# grep "^[A-Z]..$" 1.txt
[root@localhost ~]# grep "^[A-Z][a-z]*3[0-5]" 1.txt
[root@localhost ~]# grep "[a-z]*\." 1.txt
l.ve
[root@localhost ~]# grep "^*[A-Z][a-z][a-z]$" 1.txt
[root@localhost ~]# grep "^*[A-Za-z]*[^,][A-Za-z]*$" 1.txt
[root@localhost ~]# grep "\<fourth\>" 1.txt
[root@localhost ~]# grep \<fourth\> 1.txt
[root@localhost ~]# grep \<f.*th\> 1.txt
[root@localhost ~]# grep "5{2}2{3}\." 1.txt
[root@localhost ~]# grep "^[\t]*$" 1.txt
[root@localhost ~]# grep "^#" 1.txt
#qian
#yoa
#huang
[root@localhost ~]# grep "^[\t]*#" 1.txt
#qian
#yoa
#huang
:1,$ s/\([Oo]ccur\)ence/\1rence/
:1,$ s /\(square\) and \(fair\)/\2 and \1/



