- Choosing an Editor
- Starting pico and Dabbling with It
- Saving in pico
- Cutting and Pasting Text Blocks in pico
- Checking Spelling in pico
- Getting Help in pico
- Exiting pico
- Starting vi and Dabbling with It
- Saving in vi
- Adding and Deleting Text in vi
- Importing Files into vi
- Searching and Replacing in vi
- Exiting vi
- Starting emacs and Dabbling with It
- Using emacs Menus to Spell-Check
- Saving in emacs
- Exiting emacs
This chapter is from the book
This chapter is from the book
This chapter is from the book
Searching and Replacing in vi
One of vi's better features (and advantages over pico) is that it allows you to search and replace throughout entire files. As shown in the next sections, you can just find a specific string of text (a regular expression, in Unix lingo; see Figure 4.14), or you can find the text and replace it with other text, as in Figure 4.15.
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Figure 4.14 Searching for text in vi is quick and reliable.
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Figure 4.15 Replacing text in vi requires a bit of arcane syntax, but you get used to it quickly.
To find a string of text in vi:
vi hairyspider
For starters, access vi and a specific file.
/spiderEnter command mode, then type / followed by the text you're looking for. Here, we're looking for "spider," but you may be looking for "the fly" or "wiggled and jiggled and tickled inside her." Or whatever.
Press
to find the first occurrence of the term. Type n to find the next one.
To search and replace in vi:
vi hairyspider
For starters, access vi and a specific file.
- :%s/swallowed the fly/swallowed a spider to catch the fly/ Enter :%s/ plus the text to find, another /, followed by the replacement text, as in Figure 4.15. Here, we replace "swallowed a fly" with "swallowed a spider to catch the fly," but perhaps you might forego the spider and simply go for some antacid.
TIPs
- A great use for the search-and-replace feature is if you end up with DOS text files in your Unix account (by uploading a text file from a Windows machine as a binary file, most likely). If you view DOS files through a Unix shell, all the lines in the file will end with ^M. But if you try to type ^M when you're doing a search and replace, the ^M won't show up. What to do? Press
, then 
. Just search and replace with :%s/
//g. The command "escapes" the following character, so you can press it without actually doing what the command would otherwise do. If you don't escape the , vi thinks you just pressed and tries to execute the unfinished command. - See the section on grep in Chapter 6 for information about searching with regular expressions.
- Add a g at the end of the command to make it apply to all occurrences in the file. Otherwise, it applies only to the first occurrence on each line.