Metacharacters

The characters in Table 22-3 have special meaning only in search patterns.

Table 22-3. Metacharacters used in search patterns

Character

Pattern

.

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. ...

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