.
|
Match any single
character except newline. Can match newline in awk
.
|
*
|
Match any number (or none) of the single character that immediately precedes it. The preceding character can also be a regular expression; e.g., since .
(dot) means any character, .*
means "match any number of any character."
|
^
|
Match the following regular expression at the beginning of the line or string.
|
$
|
Match the preceding regular expression at the end of the line or string.
|
[ ]
|
Match any one
of the enclosed characters.
A hyphen (-
) indicates a range of consecutive
characters. A circumflex (^
) as the first character in the brackets reverses the sense: it matches any one character not
in the list. A hyphen or close bracket (]
) as the first character is treated as a member of the list. All other metacharacters are treated as members of the list (i.e., literally).
|
{
n
,
m
}
|
Match a range of occurrences of the single character that immediately precedes it. The preceding character can also be a metacharacter. {
n
}
matches exactly n
occurrences, {
n
,}
matches at least n
occurrences, and {
n
,
m
}
matches any number of occurrences between n
and m
. n
and m
must be between 0 and 255, inclusive.
|
\{
n
,
m
\}
|
Just like {
n
,
m
}
, above, but with backslashes in front of the braces.
|
\
|
Turn off the special meaning of the character that follows. |
\( \)
|
Save the pattern enclosed between \(
and \)
into a special holding space. Up to nine patterns can be saved on a single line. The text matched by the subpatterns can be "replayed" in substitutions by the escape sequences \1
to \9
.
|
\
n
|
Replay the n
th subpattern enclosed in \(
and \)
into the pattern at this point. n
is a number from 1 to 9, with 1 starting on the left. See the following Examples.
|
\< \>
|
Match characters at beginning (\<
) or end (\>
) of a word.
|
+
|
Match one or more instances of preceding regular expression. |
?
|
Match zero or one instances of preceding regular expression.
|
|
|
Match the regular expression specified before or after.
|
( )
|
Apply a match to the enclosed group of regular expressions.
|
