Metacharacters, Listed by Linux Program
Some metacharacters are valid for one program but not for another. Those available to a given program are marked by a checkmark (✓) in the following table. Notes are provided after the table, and full descriptions of metacharacters are in the following section.
|
Symbol |
ed |
vi |
sed |
gawk |
grep |
egrep |
Action |
|---|---|---|---|---|---|---|---|
|
. |
✓ |
✓ |
✓ |
✓ |
✓ |
✓ |
Match any character (can match newline in gawk). |
|
* |
✓ |
✓ |
✓ |
✓ |
✓ |
✓ |
Match zero or more preceding elements. |
|
^ |
✓ |
✓ |
✓ |
✓ |
✓ |
✓ |
Match beginning of line or string. |
|
$ |
✓ |
✓ |
✓ |
✓ |
✓ |
✓ |
Match end of line or string. |
|
\ |
✓ |
✓ |
✓ |
✓ |
✓ |
✓ |
Escape following character. |
|
[ ] |
✓ |
✓ |
✓ |
✓ |
✓ |
✓ |
Match one from a list or range. |
|
\( \) |
✓ |
✓ |
✓ |
Store pattern for later replay. | |||
|
\ n |
✓ |
✓ |
✓ |
Reuse matched text stored in nth \( \). | |||
|
{ } |
✓ |
Match a range of instances. | |||||
|
\{ \} |
✓ |
✓ |
✓ |
✓ |
Match a range of instances. | ||
|
\< |
✓ |
Match word’s beginning. | |||||
|
\> |
✓ |
Match word’s end. | |||||
|
+ |
✓ |
✓ |
✓ |
Match one or more preceding elements. | |||
|
? |
✓ |
✓ |
✓ |
Match zero or one preceding elements. | |||
|
| |
✓ |
✓ |
Separate choices to match. | ||||
|
( ) |
✓ |
✓ |
Group expressions to match. |
On some Linux systems, grep is a link to egrep, so whenever you run grep you actually get egrep behavior.
In ed, vi, and sed, when you perform a search-and-replace (substitute) operation, ...