| ^ |
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 of the preceding characters |
/ *love/ |
Match lines with zero or more spaces, followed by the pattern
love. |
| [ ] |
Matches one in the set |
/[Ll]ove/ |
Matches lines containing
love or Love. |
| [x–y] |
Matches one character within a range in the set |
/[A–Z]ove/ |
Matches letters from
A through Z followed by
ove. |
| [^ ] |
Matches one character not in the set |
/[^A–Z]/ |
Matches any character not in the range between
A and Z. |
| \ |
Used to escape a metacharacter |
/love\./ |
Matches lines containing
love, followed by a literal period. Normally the period matches one of any character. |
| Additional metacharacters are supported by many UNIX programs that use RE metacharacters: |
| \< |
Beginning-of-word anchor |
/\<love/ |
Matches lines containing a word that begins with
love (supported by vi and
grep). |
| \> |
End-of-word anchor |
/love\>/ |
Matches lines containing a word that ends with
love (supported by vi and
grep). |
| \(..\) |
Tags match characters to be used later |
/\(love\)able \1er/ |
May use up to nine tags, starting with the first tag at the left-most part of the pattern. For example, the pattern
love is saved as tag 1, to be referenced later as
\1; in this example, the search pattern consists of
lovable followed by lover (supported by
sed, vi, and grep). |
| x{m\}or
x{m,\}or x{m,n\} |
Repetition of character x, m times, at least m times, at least m and not more than n times |
o{5,10\} |
Matches if line contains between 5 and
10 consecutive occurrences of the letter o (supported by
vi and grep). |
