3.3 Movement by Searches
[/] One of the most useful ways to move around in a large file quickly is by searching for text, or more properly, a pattern of characters. Sometimes a search can be performed to find a misspelled word or to find each occurrence of a variable in a program.
The search command is the special character
A pattern can be a whole word or any other sequence of characters (called a "character string"). For example, if you search for the characters red , you will match red as a whole word, but you'll also match occurred . If you include a space before or after pattern , the spaces will be treated as part of the word. As with all bottom-line commands, press [RETURN] to finish. vi , like all other UNIX editors, has a special pattern-matching language that allows you to look for variable text patterns; for example, any word beginning with a capital letter, or the word The at the beginning of a line.
We'll talk about this more powerful pattern-matching syntax in Chapter 6, Global Replacement . For right now, think of pattern simply as a word or phrase.
vi begins the search at the cursor and searches forward, wrapping around to the start of the file if necessary. The cursor will move to the first occurrence of the pattern. If there is no match, the message "Pattern not found" will be shown on the status line.[1 ]
Using the file practice , here's how to move the cursor by searches:
The search wraps around to the front of the file. Note that you can give any combination of characters; a search does not have to be for a complete word.
To search backward, type a
In both cases, the search wraps around to the beginning or end of the file, if necessary.
3.3.1 Repeating Searches
[n] The last pattern that you searched for stays available throughout your editing session. After a search, instead of repeating your original keystrokes, you can use a command to search again for the last pattern.
Since the last pattern stays available,
you can search for a pattern, do some work, and then search again for the
same pattern without retyping it by using
To continue with the example above, since the pattern scr is still available for search, you can:
Sometimes you want to find a word only if it is further ahead;
you don't want the search to wrap around earlier in the file.
has an option,
Address search hit BOTTOM without matching pattern
This section has given only the barest introduction to searching for patterns. Chapter 6 will teach you more about pattern matching and its use in making global changes to a file.
22.214.171.124 Changing through searching
You can combine the
Note how the deletion occurs on a character basis, whole lines are not deleted.
3.3.2 Current Line Searches
There are also miniature versions of the search commands that
operate within the current line.
The in-line search commands are summarized below. None of these commands will move the cursor to the next line.
With any of these commands, a numeric prefix n will locate the n th occurrence. Suppose you are editing in practice , on this line: