Wildcards (also known as globbing) allows us to select filenames based on patterns of characters.
| Wildcard | Meaning |
|---|---|
* | matches any character |
? | matches any single character |
[characters] | matches any character that is a member of the set characters |
[!characters] | matches any character that is not a member of the set characters |
[[:class:]] | matches any character that is a member of the specified class |
Commonly used character classes:
| Character class | meaning |
|---|---|
[:alnum:] | matches any alphanumeric character |
[:alpha:] | matches any alphabetic character |
[:digit:] | matches any numeral |
[:lower:] | matches any lowercase letter |
[:upper:] | matches any UPPERCASE letter |
Examples
[[:upper:]]* : Any file beginning with an uppercase letter.
*[[:lower:]123] : Any file ending with a lowercase letter or
the numerals “1”, “2”, or “3”.
BACKUP.[0-9][0-9][0-9] : Any file beginning with “BACKUP.”
followed by exactly three numerals.
[abc]* : Any file beginning with either an “a”, a
“b”, or a “c”