Linux Regular expressions

Base regular Expressions (basic Regular expression)

Serial Number	symbols	Description	Example
1	^	To match with ... Line starting with	^ab matches lines starting with AB
2	$	To match with ... End of Line	ab$ matches lines ending with AB
3	^$	Match Blank Line	^$ matches blank lines, does not match spaces
4	.	Match any single character	AB. Match ABC or ABD, mismatch ABCD or Abde, including spaces
5	\	Escape character, escaping special symbols	A\.B match a.b, mismatch AJB
6	*	Match previous item 0 or more times	ab* match A or AB or abbb
7	.*	Match any character	ab.* Match AB or ABC or ABCD, including blank lines
8	[]	Matches any single character within the collection	AB[CD] matches ABC or ABD, does not match ABJ or ABCD
9	[^]	Match any single character outside the collection	AB[^CD] matches Abe or ABJ, does not match ABC or ABD

• Data simulation

[[email protected] ~]# vim linbin.txtI am oldboy teacher!I teach linux.I like badminton ball,billard ball and chinese chess.my blog is http://oldboy.blog.51cto.comour site is http://www.etiantian.orgmy qq num is 49000488.not 4900000448.my god,i am not oldbey,but OLDBOYoldb y

• To match with ... Line starting with

[[email protected] ~]# grep "^m" linbin.txtmy blog is http://oldboy.blog.51cto.commy qq num is 49000488.my god,i am not oldbey,but OLDBOY

• To match with ... End of Line

[[email protected] ~]# grep "m$" linbin.txtmy blog is http://oldboy.blog.51cto.com

• Match Blank Line

[[email protected] ~]# grep -vn "^$" linbin.txt1:I am oldboy teacher!2:I teach linux.4:I like badminton ball,billard ball and chinese chess.6:my blog is http://oldboy.blog.51cto.com7:our site is http://www.etiantian.org9:my qq num is 49000488.11:not 4900000448.12:my god,i am not oldbey,but OLDBOY13:oldb y

• Match any single character

[[email protected] ~]# grep "." linbin.txt  ##不匹配空行I am oldboy teacher!I teach linux.I like badminton ball,billard ball and chinese chess.my blog is http://oldboy.blog.51cto.comour site is http://www.etiantian.orgmy qq num is 49000488.not 4900000448.my god,i am not oldbey,but OLDBOYoldb y[[email protected] ~]# grep "oldb.y" linbin.txtI am oldboy teacher!my blog is http://oldboy.blog.51cto.commy god,i am not oldbey,but OLDBOYoldb y

• Escape character

[[email protected] ~]# grep "\.$" linbin.txtI teach linux.I like badminton ball,billard ball and chinese chess.my qq num is 49000488.not 4900000448.

• Match previous item 0 or more times

[[email protected] ~]# grep "0*" linbin.txtI am oldboy teacher!I teach linux.I like badminton ball,billard ball and chinese chess.my blog is http://oldboy.blog.51cto.comour site is http://www.etiantian.orgmy qq num is 49000488.not 4900000448.my god,i am not oldbey,but OLDBOYoldb y[[email protected] ~]# grep -o "0*" linbin.txt  ##精确匹配字符串00000000

• Match any character

[[email protected] ~]# grep ".*" linbin.txt  ##匹配空行I am oldboy teacher!I teach linux.I like badminton ball,billard ball and chinese chess.my blog is http://oldboy.blog.51cto.comour site is http://www.etiantian.orgmy qq num is 49000488.not 4900000448.my god,i am not oldbey,but OLDBOYoldb y

• Matches any single character within the collection

[[email protected] ~]# grep "[abc]" linbin.txtI am oldboy teacher!I teach linux.I like badminton ball,billard ball and chinese chess.my blog is http://oldboy.blog.51cto.comour site is http://www.etiantian.orgmy god,i am not oldbey,but OLDBOYoldb y[[email protected] ~]# grep "[0-9]" lb.txtmy blog is http://oldboy.blog.51cto.commy qq num is 49000488.not 4900000448.ss

• Match any single character outside the collection

[[email protected] ~]# grep "[^a-z]" linbin.txt  ##匹配非小写字母I am oldboy teacher!I teach linux.I like badminton ball,billard ball and chinese chess.my blog is http://oldboy.blog.51cto.comour site is http://www.etiantian.orgmy qq num is 49000488.not 4900000448.my god,i am not oldbey,but OLDBOYoldb y[[email protected] ~]# grep "[^A-Z]" linbin.txt  ##匹配非大写字母I am oldboy teacher!I teach linux.I like badminton ball,billard ball and chinese chess.my blog is http://oldboy.blog.51cto.comour site is http://www.etiantian.orgmy qq num is 49000488.not 4900000448.my god,i am not oldbey,but OLDBOYoldb y[[email protected] ~]# grep "[^0-9]" linbin.txt  ##匹配非数字I am oldboy teacher!I teach linux.I like badminton ball,billard ball and chinese chess.my blog is http://oldboy.blog.51cto.comour site is http://www.etiantian.orgmy qq num is 49000488.not 4900000448.my god,i am not oldbey,but OLDBOYoldb y

Extended Regular expression (Extended Regular expression)

Serial Number	symbols	Description	Example
1	+	Match previous item 1 or more times	ab+ matches AB or ABB, does not match a
2	?	Match previous item 0 or 1 times	AB matches A or AB, does not match ABB
3	The	Any one of the two sides	Ab	CD Match AB or CD
4	()	Match expression	A (c	d) e matches ace or ADE, does not match AE
5	{N,m}	Match previous item n~m times	ab{2,3} matches ABB or ABBB and needs to {} be escaped
6	{N,}	Matches the preceding item at least n times, containing n times	Ab{2,} matches ABB or ABBB and needs to {} be escaped
7	N	Match previous item n times	AB{2} matches ABB, need to {} be escaped
8	{, M}	Matches the previous item up to M times, including M times	ab{,2} matches a or AB or ABB, need to {} be escaped

• Data simulation

[[email protected] ~]# vim linbin.txtI am oldboy teacher!I teach linux.I like badminton ball,billard ball and chinese chess.my blog is http://oldboy.blog.51cto.comour site is http://www.etiantian.orgmy qq num is 49000488.not 4900000448.my god,i am not oldbey,but OLDBOYgoodgooodgd

• Match previous item 1 or more times

[[email protected] ~]# grep -E "go+d" linbin.txtmy god,i am not oldbey,but OLDBOYgoodgoood

• Match previous item 0 or 1 times

[[email protected] ~]# grep -E "go?d" linbin.txtmy god,i am not oldbey,but OLDBOYgd

• Match | Any one of the two sides

[[email protected] ~]# grep -E "god|good" linbin.txtmy god,i am not oldbey,but OLDBOYgood

• Match expression

[[email protected] ~]# grep -E "g(la|oo)d" linbin.txtgood[[email protected] ~]# egrep "g(la|oo)d" linbin.txtgood[[email protected] ~]# egrep "g(oo)?d" linbin.txtgoodgd

• Match previous item n~m times

[[email protected] ~]# grep -E "0{3,5}" linbin.txtmy qq num is 49000488.not 4900000448.

• Match the preceding item at least n times

[[email protected] ~]# grep -E "0{3,}" linbin.txtmy qq num is 49000488.not 4900000448.

• Match previous item n times

[[email protected] ~]# grep -E "0{3}" linbin.txtmy qq num is 49000488.not 4900000448.

Linux Regular expressions