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Windows PowerShell in Action
jlcopeland writes "For two decades I've hated the command prompt in DOS and Windows.
Inconsistencies abound and everything is a special case. The
fallback on a Microsoft box has been running a Unix shell under Cygwin or
installing Microsoft's
own Services for Unix (or its predecessor, Softway's Interix),
or by scripting in Perl, but those only get
you so far. Having co-written nine years worth of trade rag columns
using mostly Perl as the implementation language for the samples,
and thinking of every problem that comes across
my desk as an excuse to write a little bit of scripting code,
I've got some well-formed views about scripting languages
and what works and what doesn't. That means
I've been eagerly watching the development of PowerShell since it
was called Monad. It's got the advantage of being a unified command-line
interface and scripting language for Windows, even if it does have
a dorky name." Read the rest of Jeffrey's review.
Windows PowerShell in Action
author
Bruce Payette
pages
576
publisher
Manning
rating
9
reviewer
Jeffrey Copeland
ISBN
1932394907
summary
Guide to PowerShell, the new Windows scripting language
Bruce Payette's Windows PowerShell in Action is a great overview of PowerShell, aimed at an audience that's got some experience with other scripting languages. Bruce's book is a big improvement over Andy Oakley's earlier book, Monad, which I had been using: it's more complete and it's up-to-date for the first release of PowerShell. It's got great (and sometimes amusing) examples, and feels like the Perl Camel book in flow. When I was reading it in the gym or someplace else away from the keyboard, I kept wanting to run back to the office to try something out. There are also useful "why it works this way" digressions, which provide a lot of context. Since Bruce was on the original development team, wrote most of the commandlets, and was responsible for much of the language design, those digressions are more authoratitive than the directors' commentary tracks on most DVDs.
In outline, the nine chapters in the first part of the book build up as you'd expect: overview and concepts, to data types, to operators, to regular expressions, to syntax, to functions, to interpreting errors. It covers that ground better than many language books that now litter my shelves. The explanations are clear, and the examples are almost all exactly on point. It took me a second reading to realize that my complaints about the regular expression sub-chapter wasn't about the chapter itself, but about some of the implementation decisions; that's an argument about style more than substance, and an observation about me, not about Bruce's writing or PowerShell. The first part of the book is the "mandatory reading," if you will, to get the language down and begin exploring on your own.
The second part is where the real applications are covered. That's the part that you especially want to read sitting next to the keyboard. As you'd expect, the example code is available from the publisher's web site to start you off — look for "Example Code" under "Resources." There's a very good discussion of text processing and how-to-handle XML, complete with some not-obvious warnings about traps to avoid. I've been working very carefully through the really good chapter on using GUIs with PowerShell, "Getting Fancy — .NET and WinForms," and my own proof of concept for that has been rebuilding an old C++ data entry application into a much simpler PowerShell script. As a nice side effect, Bruce's book (and the WinForms chapter in particular) provide a gentle overview to some concepts in the .NET framework, which I hadn't had an opportunity to delve into. The appendix on using PowerShell as a management application will be especially useful to system managers; that was one of the original PoweShell target audiences, and the language achieved that goal very well. The appendix on the language's grammar is really useful, and I keep flipping back to it to check on things.
After Oakley's Monad appeared, there was a long gap before the next PowerShell book appeared. Bruce's book looks to be the first of the post-release wave. If all it had going for it was the authoratative pedigree of the writer, it might be worth it, but it's also well-written, well-organized, and thorough, which I think makes it invaluable as both a learning tool and a reference.
You can purchase Windows PowerShell in Action from amazon.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.
Bruce Payette's Windows PowerShell in Action is a great overview of PowerShell, aimed at an audience that's got some experience with other scripting languages. Bruce's book is a big improvement over Andy Oakley's earlier book, Monad, which I had been using: it's more complete and it's up-to-date for the first release of PowerShell. It's got great (and sometimes amusing) examples, and feels like the Perl Camel book in flow. When I was reading it in the gym or someplace else away from the keyboard, I kept wanting to run back to the office to try something out. There are also useful "why it works this way" digressions, which provide a lot of context. Since Bruce was on the original development team, wrote most of the commandlets, and was responsible for much of the language design, those digressions are more authoratitive than the directors' commentary tracks on most DVDs.
In outline, the nine chapters in the first part of the book build up as you'd expect: overview and concepts, to data types, to operators, to regular expressions, to syntax, to functions, to interpreting errors. It covers that ground better than many language books that now litter my shelves. The explanations are clear, and the examples are almost all exactly on point. It took me a second reading to realize that my complaints about the regular expression sub-chapter wasn't about the chapter itself, but about some of the implementation decisions; that's an argument about style more than substance, and an observation about me, not about Bruce's writing or PowerShell. The first part of the book is the "mandatory reading," if you will, to get the language down and begin exploring on your own.
The second part is where the real applications are covered. That's the part that you especially want to read sitting next to the keyboard. As you'd expect, the example code is available from the publisher's web site to start you off — look for "Example Code" under "Resources." There's a very good discussion of text processing and how-to-handle XML, complete with some not-obvious warnings about traps to avoid. I've been working very carefully through the really good chapter on using GUIs with PowerShell, "Getting Fancy — .NET and WinForms," and my own proof of concept for that has been rebuilding an old C++ data entry application into a much simpler PowerShell script. As a nice side effect, Bruce's book (and the WinForms chapter in particular) provide a gentle overview to some concepts in the .NET framework, which I hadn't had an opportunity to delve into. The appendix on using PowerShell as a management application will be especially useful to system managers; that was one of the original PoweShell target audiences, and the language achieved that goal very well. The appendix on the language's grammar is really useful, and I keep flipping back to it to check on things.
After Oakley's Monad appeared, there was a long gap before the next PowerShell book appeared. Bruce's book looks to be the first of the post-release wave. If all it had going for it was the authoratative pedigree of the writer, it might be worth it, but it's also well-written, well-organized, and thorough, which I think makes it invaluable as both a learning tool and a reference.
You can purchase Windows PowerShell in Action from amazon.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.
Unless MS rewrites all of their other commands to accept STDIN/OUT, Monad will never surpass the shells. The power of the shells isnt' their programming flexibility, it's their ability to incorporate all the other UNIX tools and commands via pipes to do what you want.
Another reason it will never surpass the shells. They're lightweight, and flexible, and I don't need a Garbage Collector running in the back end to clean up my object allocation.
This space for rent. Call 1-800-STEAK4U
For those that didn't get it, his comment was a play on the famous:
"Those who do not understand Unix are condemned to reinvent it, poorly"
Saying Java is nice because it works on all OS's is like saying that anal sex is nice because it works on all genders.
You mean again?
"It ain't a war against drugs.it's a war against personal freedom" --Bill Hicks
Wake me up when *nix gets an object-oriented (rather than text-oriented) shell. Because that is what makes Powershell so unique. Yes, it has plenty of builtin functions to make tasks easier, but the real advantage is that everything you pass between commands is an object.
You don't have to worry about interpreting text output - you just access whatever data you want directly. Many of the commands are easily chainable into something like "ls | select fullname,length | sort name | format-list | out-printer".
You forgot MKS toolkit which has most if not all of the standard UNIX utilities along with vi, bash, ksh, sh, awk, sed, etc. What more could you want?
It really fails in two places. Firstly, it's slow. You wouldn't have thought it possible for a command shell to be that slow, but it is. It's so slow it was actually quicker for me to use explorer. It is god-awfully, mind-bogglingly slow.
The second problem is that it had no easy way of being accessed over a network link, last time I looked at it. So there's no chance of SSHing into a Windows box and administrating it from there, at least not without fiddling with a lot of hacks and workarounds I couldn't get to work.
The other place where unix shells have an advantage over Powershell is in there interface, as Powershell is currently quite basic in that department. There's limited tab completion and a prompt that can be altered (like PS1 under sh derivitives), but not much over that. Certainly nowhere near my personal favourite, Fish. Another reason it will never surpass the shells. They're lightweight, and flexible, and I don't need a Garbage Collector running in the back end to clean up my object allocation. Why so closed-minded? Powershell has a lot of interesting ideas, and an architecture that's structurally very well organised. Don't dismiss it just because it was made by Microsoft, especially since it sounds as if you haven't even tried it out.
in the specific case of diffing the contents of two directories, it's just
$> diff --brief a/ b/
It just seemed worth pointing out.
The FOR command in the "legacy" Windows shell is pretty powerful, too. It even has horrible syntax, just like its UNIX fathers.
Yes, the legacy Windows shell sucks, but not as badly as most people assume. The NT shell can do a lot of stuff that most people don't even think to try. Great gobs of functionality have been added over the years, starting with Windows NT 3.5. And contrary to what many slashdotters think, the legacy shell on Windows NT-derived systems is not DOS, nor is it 16-bit. CMD.EXE is just another 32-bit or 64-bit process running on the NT kernel.
That is not the case. I gave it the name Monad because of my respect for Leibniz. Wikipedia has this right: http://en.wikipedia.org/wiki/Windows_PowerShell