3.2. Extended grep (grep -E or egrep)

The main advantage of using extended grep is that additional regular expression metacharacters (see Table 3.4) have been added to the basic set. With the -E extension, Gnu grep allows the use of these new metacharacters.

Table 3.5. egrep's Regular Expression Metacharacters
Metacharacter Function Example What It Matches
^ Beginning of line anchor ^love Matches all lines beginning with love.
$ End of line anchor love$ Matches all lines ending with love.
. Matches one character l..e Matches lines containing an l, followed by two characters, followed by an e.
* Matches zero or more characters *love Matches lines with zero or more spaces, of the preceding characters followed by the pattern love.
[ ] Matches one ...

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