![]() ![]() You are also expected to get comfortable with reading manuals, searching online, visiting external links provided for further reading, tinkering with illustrated examples, asking for help when you are stuck and so on. You should also be comfortable with concepts like file redirection and command pipelines. You should be familiar with command line usage in a Unix-like environment. Two different implementations are discussed in this book - GNU grep and ripgrep.Įxercises are also included to test your understanding. In addition to command options, regular expressions will also be discussed in detail. This book heavily leans on examples to present features one by one. An important feature that GUI applications may lack is regular expressions, a mini-programming language to precisely define a matching criteria. The grep command is a versatile and feature-rich version of that search functionality usable from the command line. It's a crazy fun project to work on when I have time.You are likely to be familiar with using a search dialog (usually invoked with the Ctrl+F shortcut) to locate the occurrences of a particular string. I enjoy working now and then on deep and challenging coding projects, such as ugrep. There are always assumptions and requirements that affect the results wildly (I am a professor in CS and spent my entire career as a researcher, including in the area of high-performance computing.) Many in my domain of expertise realized already over a decade ago that it is a folly to pursue "the best performance" when the variety of architectures is vast and hardware and software are still evolving, even when slowly. There are a lot of opinionated folks when it comes to performance. Having said that, ugrep is relatively new and still evolving. But I believe we accomplished that goal reasonably well. None of the ugrep perf tests skip files or directories and includes all hidden files/directories, binary files, and compressed files.Ĭombining all these requirements and suggestions by users into ugrep wasn't trivial. They also suggested that ugrep should be compatible with GNU grep's options and not try to be "too clever" to skip files and directories, at least not out-of-the-box. As long as ugrep is very fast, they are more than happy. In my conversations with ugrep users, performance is not their top concern but having these new features that ugrep offers that other grep lack. Secondly, I am glad to see that ugrep is useful to many others. Most of the grep tools just use what is already available publicly and aren't doing something new that is clever, with the possible exception of hyperscan. Of course, it would be nice to receive some recognition and not get ripped off. For a while I contemplated filing a utility patent, but did not move forward on that because I want this technology to be freely available to everyone and not proprietary. I will gladly share this method publicly eventually in a technical paper. This was then compared to the best-known algorithms I could find and implemented in C (tested in memory, not on files and not reported in the ugrep project). ![]() This method is extensively tested with many configurations of parameters to find the optimal parameterization as tested on several machines. Why? For example to look for differences that explain bugs, for finding potential vulnerabilities in older software that is archived, and to check for open source licenses/violations.Īt the same time, I worked on designing a new fast pattern matching method that in simple wording uses logic/hashing to detect possible matches fast, before performing a regex match that is more CPU expensive. And narrowing down the file type of the archive contents to source code when necessary. So what is going on with the new ugrep tool? Īs a small organization specializing in open source software we needed a search tool like grep but updated to handle many compression formats including tarballs, with filters to search PDF, DOCX, and other formats. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |