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PowerShell is open sourced and is available on Linux

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Re: PowerShell is open sourced and is available on Linux

#731

Post by 0x6c6f6c »

useerup wrote: post #700
userbinator wrote: post #597

Earlier quoted context omitted.

You can certainly print them, but there's no guarantee you'll get all its contents by default, and there's still the problem of how to create those objects from some other output, e.g. in a file. http://windowsitpro.com/powershell/powershell-objects-and-ou... It could be said that, in some ways, unstructured streams are far more WYSIWYG, which can conceptually mean easier understanding and use.

> You can certainly print them, but there's no guarantee you'll get all its contents by default, and there's still the problem of how to create those objects from some other output, e.g. in a file. That's what CliXML is for. Export-CliXml writes objects to a file. Import-CliXml reads them back.

I think they're assuming the default view output is being used for Export-CliXML, when really it's serializing the object passed to it.

Re: PowerShell is open sourced and is available on Linux

#732

Post by vasilia »

ygra wrote: post #621
vasilia wrote: post #574

Earlier quoted context omitted.

And how to delete files older 2 days? Get-Files / | select olderThan 2 | Delete-File ? But it's not bash, it's coreutils find ./ -mtime +2 | xargs rm

Get-ChildItem -File | Where-Object LastWriteTime -lt (Get-Date).AddDays(-2) | Remove-Item If you prefer shorter (and similarly obscure if you don't know the language): ls -file|? LastWriteTime -lt ((date)+'-2')|rm I actually find PowerShell's version more readable, even if more verbose. But code is written only once and read a lot of times. I may not know what the +2 actually means with the -mtime argument. How would…

> I actually find PowerShell's version more readable, even if more verbose.

Sorry, I can't agree with you.

> I may not know what the +2 actually means with the -mtime argument. How would I change it to look for the age of two hours instead of days?

If you forget or doesn't know what is mtime, you can open man find. For less granularity than days use mmin.

Re: PowerShell is open sourced and is available on Linux

#733

Post by KirinDave »

daveloyall wrote: post #727
KirinDave wrote: post #464

Earlier quoted context omitted.

I have no time for tool worship, language worship, and other sentiment like that. These are tools, not people. I'll use the best I can buy, borrow, or make until I see another better one comes along.

A corporation has no incentive to give you (let you keep forever) the best possible tools.

If that is true, then it is equally true of the authors of shells.

But of course, it's not true. Many great and lasting tools have been founded out of corporate work in a bid to improve mindshare and ease recruiting by increasing the esteem of corporate engineering efforts. Many of the things we think of as "open source" and "free" were built subsidized either directly or indirectly by capitalistic interest.

But I'm not concerned about keeping it. Ossifying my process so that I can give myself the luxury of time of from learning is not something I'm prepared to do, because I think it will make me soft and less capable as an engineer. I regularly rotate my editors and learn new languages because I don't want to become like the sad specters of the previous generation of software engineers I see now, starched shirts and ties and a fanatical devotion to the dated technologies they stomach in order to collect huge consulting fees from corporations.

I've switched off Fish to Powershell as my primary shell for awhile. It's interesting.

Re: PowerShell is open sourced and is available on Linux

#734

Post by ldiracdelta »

yread wrote: post #639
ldiracdelta wrote: post #180

Earlier quoted context omitted.

I don't see a tremendous amount of accumulated wisdom in Powershell. It may be newer, but I'm not sure they looked at prior art or had design members who were shell gurus in any other shell than `cmd.exe`, which is a horrific shell. Why are commands horrendously long in powershell? If you spend time in the shell, you don't want your fingers falling off due to overuse. Aside... one of the design decisions Microsoft to…

> using `\` for file hierarchies instead of `/` You know you can use both since like XP, right? You can even mix them up in one path which can look quite confusing c:/windows\system32/etc/drivers\

`/` is not a first class citizen. You encounter different oddities throughout the windows environment in the shell and external utilities when you use `/`.

Re: PowerShell is open sourced and is available on Linux

#735

Post by ksk »

vasilia wrote: post #574
ksk wrote: post #256

Earlier quoted context omitted.

Could you elaborate on what the actual complexity is, rather than what you imagine? For a developer writing a tool, exposing an interface as objects is far easier than having to constantly serialize data into a string. Keep in mind that once you serialize data into a string, you can never change the order of the data or else other tools will break. Not so with a object based interface. In other system-admin type task…

And how to delete files older 2 days? Get-Files / | select olderThan 2 | Delete-File ? But it's not bash, it's coreutils find ./ -mtime +2 | xargs rm

Just as an aside (and this probably applies to powershell as well), what if you have mapped folders from multiple servers into your file system and those servers are in different timezones? Something like

  /Mapped-Temp-folders/Server-Asia/temp
                      /Server-UK/temp
                      /Server-Japan/temp
I guess the script wouldn't work then if you wanted to clean out data older than 2 days, as per their timezone.

Re: PowerShell is open sourced and is available on Linux

#736

Post by ksk »

ubernostrum wrote: post #543
ksk wrote: post #256

Earlier quoted context omitted.

Could you elaborate on what the actual complexity is, rather than what you imagine? For a developer writing a tool, exposing an interface as objects is far easier than having to constantly serialize data into a string. Keep in mind that once you serialize data into a string, you can never change the order of the data or else other tools will break. Not so with a object based interface. In other system-admin type task…

As someone who recently got his first exposure to PowerShell, I'll chime in that the case I needed to deal with was one where it added complexity. In summary: I need to pull data from a company we're partnered with, and get it into our systems. They ship it as SQL Server backup files. OK, no big deal, we can mount those up and run queries to dump stuff out to whatever format we like and ingest it. Except part of that…

Its true that powershell being a new tech probably doesn't have the large library of "known ways" to do things that the UNIX world has. And BTW I'm not even a powershell person. I write embedded software in C++ for a living ! Having said that, I'd imagine you would parameterize something like

  Invoke-Sqlcmd -Query "SELECT ..." and write it out to a file?
or avoid it and just use BCP "select blah" queryout "c:\file.jpg" etc etc

Re: PowerShell is open sourced and is available on Linux

#737

Post by jjnoakes »

qwertyuiop924 wrote: post #722
jjnoakes wrote: post #681

Earlier quoted context omitted.

The motivation for PowerShell was to have something good at both. Why switch contexts when moving from interactive use to coded automation if you don't have to?

Because the requirements change depending on which one you're doing: quick shell automation isn't the same as the kind of automation you'd use perl/python for.

And yet most of the time I see bash being used for the same kind of automation that you think is good for perl/python.

And not because bash is good, but because it is what people know (since they use it interactively) and because it is installed everywhere.

So if someone had a tool that was installed everywhere, and used interactively, that could also be used to create more robust automation tasks, that seems like a win to me.

Re: PowerShell is open sourced and is available on Linux

#738

Post by Const-me »

tracker1 wrote: post #649
Const-me wrote: post #563

Earlier quoted context omitted.

Live objects don’t usually expose any protocols at all. They only expose an ABI. Do you know any platform-agnostic OO ABI, besides what’s in .NET? If you’ll wrap your objects into some platform-agnostic protocol like JSON, you gonna waste enormous amount of CPU time parsing/formatting those streams at the object’s boundaries.

You can run streams of many millions of JSON objects pretty much as fast as the IO can feed it... most of the time, in situations like this, you're constrained by IO speed, not CPU... assuming you are working with a stream that has flow control. I tend to dump out data structures to line terminated JSON, and it works out really well for streams, can even gz almost transparently. Parse/stringify has never been the bot…

Even if printing and parsing is computationally cheap, memory allocation is less so.

If you expose JSON, each serialize/deserialize will produce another instances of objects, with the same data.

The architecture of PowerShell implies commands in the pipeline can process the same instances, without duplicating them.

Another good thing about passing raw objects instead of JSON — live objects can contain stuff expensive or impossible to serialize. Like an OS handle to an open file. Sure, with JSON you can pass file names instead, but this means commands in your pipeline need to open/close those files. Not only this is slower (opening a file requires kernel call, which in turn does various security checks for user’s group membership and file system’s inherited permissions), but can even cause sharing violations errors when two commands in the pipeline try accessing the same file.

Re: PowerShell is open sourced and is available on Linux

#739

Post by yellowapple »

CrLf wrote: post #506
Analemma_ wrote: post #6

PowerShell is my guilty pleasure of the computing world. Once you've piped strongly-typed objects around between your shell commands, text scraping seems barbaric by comparison. The problem, of course, is that you can't use all that power for much, since the pool of PS-compatible tools and utilities is much shallower than it is for Unix shells. I'm really hoping this will help spur a new wave of PowerShell-compatible…

After a number of years using PowerShell, my conclusion is the opposite: text "scraping" is just better for most cases. Normal shell usage means doing a lot of one-shot pipelines incrementally. This is just easier and faster to do when passing text around because you can look at it and not have to inspect some object for it's type and what attributes/methods it provides. Parsing the text is not the problem here (alth…

This is all a big part of the reason why I personally advocate using a standardized text-based object serialization format (like YAML) for these sorts of things. In particular:

* Still text based and human-readable, which helps for debugging/troubleshooting * Still text-based and machine-readable, so it's inherently cross-platform (assuming that all said platforms agree on their text encoding) * Still less troublesome than piping arbitrary text through `grep` or `sed` or `awk` or what have you * Still provides the "everything is an object" benefit that's lost with arbitrary text streams * Still orientable around streams of data, at least for YAML (by using the document delimiter)

Re: PowerShell is open sourced and is available on Linux

#740

Post by kuschku »

qwertyuiop924 wrote: post #710
kuschku wrote: post #707

Earlier quoted context omitted.

Which I’d be very happy about – see also the discussion about getting the ip for an interface above.

Are you out of your mind? Or do you just not understand what you're saying? Adding an interface to PS to get this info natively is good. But Lennart has a magic ability to get everything wrong, and he's NOT messing with my fstab any more than he already has.

Then which audio system is simple to set up AND allows per-program volume, effects, etc?

Which init system "just works" without requiring me to copy and modify a hacky init script from stackoverflow?

Lennarts products are controversial, but they’re the classical "least worst" options.

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