WICKED COOL. SHELL SCRIPTS. 2ND EDITION. Scripts for Linux,. OS X, and UNIX Systems by Dave Taylor and. Brandon Perry. Wicked Cool Shell Scripts - Scripts For Linux, Mac OS X, And Unix Systems Wicked Cool PHP: Real-World Scripts That Solve Difficult Problems. Full shell scripts for the second edition of Wicked Cool Shell Scripts - brandonprry /wicked_cool_shell_scripts_2e.

Wicked Cool Shell Scripts Pdf

Language:English, Japanese, Portuguese
Published (Last):02.12.2015
ePub File Size:25.55 MB
PDF File Size:12.58 MB
Distribution:Free* [*Register to download]
Uploaded by: KRISTINE

Wicked Cool Shell Scripts, 2nd Edition is a collection of fun tools for sysadmins, web developers, and every Linux user. Ebook (PDF, Mobi, and ePub), $ dozens of wicked cool shell scripts, ranging from an interactive calculator to a . This assumes that you're in the Wicked Cool Shell Scripts script directory! for just about any type of file, whether it's a graphics image, a PDF. Download as PDF, TXT or read online from Scribd . dozens of wicked cool shell scripts, ranging from an interactive calculator to a stock ticker monitor, and a.

If you've done any scripting, you already know this.

Spaces in filenames can cause great trouble in shell scripts! Don't get me started on having an escape character or non-printable character in the name though.

It's doable, but I'd rename it as soon as possible. The most common error is to forget to quote filenames when you use them elsewhere in the script, of course.

You May Like

As an example, let's work on a script that replaces spaces in filenames with underscores. It would be absolutely correct if used a return statement on it's own: return; Instead, he returns undef explicitly: return undef; [download] That's a minor mistake, you can get away with it so long as the subroutine is not called in a list context. Unfortunately, that's exactly how the routine is being called. It is expected to return a list of values it has found, the return value being stored in an array.

Later, a loop iterates over the contents of the array, producing some final processing and generating output.

Wicked Cool Shell Scripts - 2E (2015).pdf - D N N O 2 TI I...

The problem with returning undef, rather than merely returning, is that rather than generating an empty list, the code produces an array with one element, 'undef'. So the final loop iterates once, and produces an empty line of output, even though no values were found.

Now that's not a mortal sin, and not something I would flame someone for, if I saw it in a minor script from someone who is trying to improve his Perl. Other problems include the use of prototypes, the use of C-style loops rather than Perlistic iteration, and more.

Prototypes were a brilliant idea when they came onto the scene, 5 or 6 years ago, unfortunately they create more problems than they solve. This Book Is for You If As with any technical book, an important question for Wicked Cool Shell Scripts is whether this book is for you.

While it's certainly not a primer on how to use the Unix, Linux, or Mac OS X shell to automate tasks, and it doesn't list all the possible conditional tests that you can utilize with the t e st command, this book should nonetheless be engaging, exciting, and stimulating for anyone who has ever delved into the murky world of shell scripting.

If you want to learn how to write a script, well, there are lots of great references online. But they all have one thing in common: They offer dull, simple, and uninteresting examples. Instead, this book is intended to be a cookbook, a sort of "best of" hacks compendium that shows the full and remarkable range of different tasks that can be accomplished with some savvy shell script programming.

With lengths ranging from a few dozen lines to a hundred or more, the scripts in this book should not just prove useful, but will hopefully inspire you to experiment and create your own shell scripts too. And if that sounds interesting, well, this book is definitely for you. What Is a Shell Script, Anyway? Time was years ago when hacking was considered a positive thing.

Hackers were people on the cutting edge of computer use, experimenting with and trying novel and unusual solutions to solve existing problems. These were people who changed the way the rest of us looked at computers and computing.

Wicked Cool Shell Scripts: 101 Scripts for Linux, Mac OS X, and Unix Systems

But as the public network became more pervasive, a subset of these hackers started to migrate to remote system break-in missions, with a zeal that rather overwhelmed the rest of us. Nowadays, many consider hacking a bad thing, as in "hacking into the secure Department of Energy database.

Which Shell? There are at least a dozen Unix shells floating around, but they're all based on two major flavors: Bourne Shell sh and C Shell c s h. It is a lot more than just a reimplementation of a year-old command shell, however; it's both a great scripting environment and a highly capable interactive user shell. And then there is the C Shell, UC Berkeley's most important innovation in the realm of shell script hacking. The C Shell replaced the odd Bourne Shell syntax with a command syntax more like its namesake language, C.

As with many facets of Unix, passions are strong about which scripting environment is the best, with three predominant camps: Bourne Shell, Korn Shell, and C Shell.

But all is not equal. Consider the well-known article "Csh Programming Considered Harmful" [1 ] whose author, Tom Christiansen, points out, quite correctly: I am continually shocked and dismayed to see people write test cases, install scripts, and other random hackery using the c sh. The c s h is seductive because the conditionals are more C-like, so the path of least resistance is chosen and a c s h script is written. Sadly, this is a lost cause, and the programmer seldom even realizes it, even when they find that many simple things they wish to do range from cumbersome to impossible in the csh.

I agree wholeheartedly with Tom, and hence in this book we will eschew the use of the C Shell. If you're a strong advocate of the C Shell, well, you should find it easy to rewrite almost all of the scripts in this book to fit your shell. Similarly, many people are advocates of the Korn Shell, which has a terrific interactive command line but, I feel, is less capable as a scripting environment.

Item Preview

When evaluating a shell, consider both its interactive capabilities such as aliases, command-line history, on-the-fly spelling corrections, helpful error messages and its scripting capabilities. This book focuses on the scripting side of things, and so the scripts presented here will be Bourne Shell scripts with an occasional sprinkling of bash or POSIX shell tweaks for entertainment value and should work just fine on any Unix you may have.

The Solaris Factor If you're working on a Solaris system, you've got a bit of a problem, but not one that can't be solved.

So what's the problem? Fortunately, you can fix it, in one of two ways: 1. This might be a bit radical, and there's a tiny chance it'll break other things in Solaris, so I'd be cautious about this choice. In every single script in this book, replace the! This has the added advantage of allowing you to automate the process with a f or loop similar to the following: T his ass u mes tha t yo u'r e in the Wic ked Co ol S hell Scr ipts sc ript dir ecto ry!The list of files modified since the previous backup is built with fi nd and saved in the inc l i st temporary file.

These alternatives are available as part of the latest Red Hat Linux distribution. The requesting script waits and tries again. But all is not equal.

You might also like: GOOSE GIRL SHANNON HALE PDF

But what if you have users across multiple time zones? Compare this with the following ouput. The place of social Otherness was the Converted release and improved new education.

The Code Two scripts are necessary for a secure locate: