Metacharacters
The following characters have special meaning in search patterns:
Character |
Action |
---|---|
. |
Match any single character except newline. |
* |
Match any number (or none) of the single character that immediately precedes it. The preceding character also can be a regular expression (e.g., since . (dot) means any character, .* means match any number of any character—except newlines). |
^ |
Match the beginning of the line or string. |
$ |
Match 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. |
[^ ] |
Match anything except enclosed characters. |
\{ n,m \} |
Match a range of occurrences of the single character that immediately
precedes it. The preceding character also can be a regular
expression. \{
n
\} matches exactly
|
{ n,m } |
Like \{ n,m \}. Available in grep by default and in gawk with the -Wre-interval option. |
\ |
Turn off the special meaning of the character that follows. |
\( \) |
Save the matched text enclosed between \( and \) in a special holding space. Up to nine patterns can be saved ... |
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