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I'm studying for exam 101, the first of two exams which comprise the first of three possible certifications from the Linux Professional Institute (LPI), or, simply, the LPIC-1. There will be six installments, give or take, charting my learning experience from layman to exam 101 certificate holder. In the articles, I'll share what I've learned about the exam itself, including syllabus content, resources and useful tips, as well as – where appropriate – my learning methods. In the future, I would also like to incorporate any information I can gather regarding my (hopefully!) improved employability as I (again hopefully!) progress through the curriculum and gain skills. In short, this article is ideal for anybody toying with the idea of investing time in learning for this qualification in the hope of landing a *buntu/Linux job. The Exam The first reality of exam 101, which wasn't immediately obvious to me, is that the exam doesn't take place at the command-line. It's a multiple-choice test comprised of 60 questions to be completed in 90 minutes. This approach makes sense – for the examiners at least. Consider being presented with the following question testing the candidate's knowledge of how to redirect standard input, output and error streams: Q: You want to store the standard output of the ifconfig command in a text file (file.txt) for future reference, and you want to wipe out any existing data in the file. How can you do so? a. ifconfig < file.txt b. ifconfig » file.txt c. ifconfig > file.txt d. ifconfig | file.txt (© Smith, R.W., Linux Professional Institute Certification: Study Guide, Second Edition. Wiley, Indiana: USA, 2009). At the command-line, the candidate could simply execute each command in turn and examine the results to arrive at the correct answer. In multiple-choice format, the candidate must be able to distinguish between the function of » and >, which is key to answering this question correctly. If file.txt exists, > overwrites any existing content whereas » would append to existing content. Both > and » create file.txt if the file doesn't exist. (In this sense, the question is badly worded as it doesn't clarify explicitly if file.txt exists or not.) To sum up, if the testing took place at the command-line, no knowledge would be tested, yet, in multiple-choice format, the most nuanced differences are tested. Furthermore, the multiple-choice format eliminates the candidates' access to the man pages. Admittedly somewhat artificial, but effective in separating the wheat from the chaff.
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Syllabus content and something useful The first section of the book I'm working with, “Linux Professional Institute Certification 1”, explores Linux command-line tools, that is, text streams, filters, pipes, redirects and search, as well as search and replace with regular expressions. The commands covered in this section are: internal bash commands (exec, exit/logout, pwd, cd, time, set, echo); shell hotkeys (e.g. how to change lowercase to uppercase at the command-line – more on these later); >, », <, «, 2>, 2», &> and <>; | (pipes); cat, join, paste, od, sort, split, tr, unexpand, uniq, fmt, nl, pr, head, tail, less, more, cut, wc, grep and sed. Coverage of grep and sed is not exhaustive: as a case in point, an entire volume has been published on sed functionality alone. To finish, many of the commands I've learnt, I can't, as of yet, put to good use. For example, I don't have the need to study the structure of a graphics or audio file (usually non-ASCII) by using od (octal dump). But this is often the case with learning something new: one must be patient until one reaches a sort of critical mass, where knowledge suddenly becomes useful. And on that note, I would like to leave you with something useful I've learned: it's a shell hotkey for searching your command history. Hit Crtl+R at the command-line, and start typing characters (the characters don't have to correspond to the first letters of the command or path you are searching). When you've found the command or path you want, hit ENTER to execute it, or hit Crtl+G to return empty handed to the command-line. Und tchuss. (German for cheerio) In my next article, I'll have a look at learning methods and resources as well as more on syllabus content. That's it for now.