Regular expressions are a powerful tool that can be used to search and replace text in a document. However, on Linux, regular expressions can be difficult to use because of the lack of a built-in regex engine. To overcome this obstacle, you can use Regexxer, a free software regex engine that is available online. Regexxer is easy to use and can be installed on any Linux computer. Once installed, you will need to create a file called ~/.regexes in your home directory. This file contains the following:
Regular expression pattern # Matching text against the pattern # The text to search for # The replacement text # The exit status of Regexxer
The first line of the file contains the regular expression pattern. This is an example: /^([a-zA-Z0-9]$/).?$/i . The asterisk (*) indicates that Regexxer should match any character in the string except for those specified by the $ . The second line contains the text to search for. In this case, it means that Regexxer should look for all occurrences of “apple” in the document and replace them with “banana”. The third line contains the replacement text. In this case, it means that Regexxer should look for all occurrences of “apple” and replace them with “banana” followed by any other letters or numbers that are found in the string “apple”. Finally, there is an exit status field which tells Regexxer how many times it has been run (the number after * ). If everything goes well (the number after i ), then Regexxer will have replaced all instances of “apple” with “banana” and exited successfully. If there are any errors (the number after e ), then Regexxer will have
Reader Sergio turned us on to this great application geared towards programmers, but it could be useful for any hard-core geek, especially since it’s a nice little standalone package.
Installation for Debian/Ubuntu
The great thing about this utility is that you can step through and confirm whether to replace or skip for each file that is found. Just enter your regular expression or keyword into the search box and hit the Find button.
The application will find the first file and show you the suggested change in the small textbox below, and you can choose to replace or hit the arrows to go to the next file.
The only thing that this app is really seriously lacking is the ability to save searches for later use. It’s no PowerGrep, but it’s free and open source.
Visit regexxer homepage at SourceForge
