Examples of Searching
When used with
grep or
egrep, regular expressions should be surrounded
by quotes. (If the pattern contains a $, you must
use single quotes; e.g., 'pattern‘.) When used
with ed, ex,
sed, and awk, regular
expressions are usually surrounded by /, although
(except for awk) any delimiter works. Table 22-6 through Table 22-9 show some
example patterns.
Table 22-6. General search patterns
|
Pattern |
What does it match? |
|---|---|
|
|
The string |
|
|
|
|
|
|
|
|
|
|
|
Bag or bag. |
|
|
Second letter is a vowel. |
|
|
Second letter is a consonant (or uppercase or symbol). |
|
|
Second letter is any character. |
|
|
Any line containing exactly three characters. |
|
|
Any line that begins with a dot. |
|
|
Same, followed by two lowercase letters (e.g., troff requests). |
|
|
Same as previous; ed, grep, and sed only. |
|
|
Any line that doesn’t begin with a dot. |
|
|
bug, bugs, bugss, etc. |
|
" |
A word in quotes. |
|
" |
A word, with or without quotes. |
|
|
One or more uppercase letters. |
|
|
Same; egrep or awk only. |
|
|
Same; POSIX egrep or awk. |
|
|
An uppercase letter, followed by zero or more characters. |
|
|
Zero or more uppercase letters. |
|
|
Any letter. |
|
|
Any symbol or space (not a letter or a number). |
|
|
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