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I work primarily in a Microsoft environment, although I have Linux shell experience as well, and I totally don't get Powershell. What is a cmdlet? Why does it n

• wvenable 11y ago
  I find Powershell extremely weird. We have a fair number of Powershell scripts for admin tasks and frankly I think they'd all be easier to understand if they were just written in C#.
  • zub 11y ago
    Mhmm. I wrote a set of PowerShell scripts to do some basic deployment stuff a while back and I discovered... - Timing issues with something as simple as "remove file," where the agreed upon Stack Overflow solution was to call it "a few more times until you didn't get an error." - Broken implementations of recursive folder copy. - Okay, we'll call upon "rm" and "rmdir" -- oh, PowerShell intercepts those and invokes the previously described buggy routines. (Eventually figured out that I needed to shell out completely.) In the end I regretted writing these crummy house-of-cards PowerShell scripts.
  • deleted 11y ago
    [deleted]
    • jfb 11y ago
      Well, to be fair, in 2002 it was far from clear that there were going to be millions of C# programmers.
• nailer 11y ago
  As a Unix person, 'Restart-Service' seems a lot easier to remember than 'systemctl'. Edit: Restart-Service is also easier to remember than /etc/init.d was. Edit 2 (rate limit): `service` on RHEL is great, but it's a Red Hat-ism. Which is fine, I used to work at Red Hat, but still. It's also pretty limited: you use service to start/stop/restart, but you still use systemctl to list services, or list /etc/init.d (technically /etc/rc.d/init.d on RHEL) on older boxes. On Windows, to get services, it's `get-service` Fun exercise for readers, given that you now know `restart-service` and `get-service`: - Guess what the powershell command to get processes is. - Guess what the powershell command to stop a process is. - Guess what the Powershell command to install a package is. There's some weird ones - dmidecode on Linux becomes get-wmiobject on Powershell (see the rosetta stone link posted earlier) - but for the most part it makes more sense than Linux and Unix.
  • mcguire 11y ago
    Restart-Service:Windows :: service:RHEL ?
  • vezzy-fnord 11y ago
    It's not like 'systemctl' is the only game in town, though.
    • deleted 11y ago
      [deleted]
    • itaibn 11y ago
      You say that as if that makes remembering things easier.
  • tokenizerrr 11y ago
    What about service apache2 restart
    • yellowapple 11y ago
      Or /etc/rc.d/apache2 restart, as one would find in the BSD world (and Slackware, with a bit of modification). This isn't to mention that it should be relatively trivial to map "restart-service $foo" to "/etc/rc.d/$foo restart" or "systemctl $foo.service restart" or whatever if one so chooses.
      • nailer 11y ago
        Sure you could write functions or aliases to everything to give them more predictable names. But you shouldn't have to.
      • bbatha 11y ago
        FreeBSD uses the service command these days too.
        • 11y ago
• scott_karana 11y ago
  Powershell cmdlets are different(ly named) than executables/commands because they don't preferentially emit text: they emit .NET object streams. I suspect this is for compatibility/interrop reasons. (They are implemented as .NET classes loaded from within libraries, as I recall. Eg, `import-module activedirectory` will load the entire library of AD cmdlets.) Here's what you can do with object streams: Get-ADUser | select FirstName,LastName,EmailAddress,Department | where {$_.FirstName -contains "Jeffery"} | format-table In a traditional Unix pipeline, you'd have to make sure that none of the other fields contained "Jeffery", or you could get false positive results. For example, you might have to use multiple named pipes or temporary files for each of the table columns, and reinterpolate them into a table/CSV/whatever after doing the grep. You could always use Python/Perl/Ruby/Tcl instead of course, but those aren't really shells. You can also do math, method calls, etc. The example above was just a trivial one.
• Canada 11y ago
  A cmdlet is a PowerShell native command. It reads and writes objects, where as Unix commands read and write plain text. Try this in PowerShell: get-command get-command | where CommandType -eq "alias" Notice the lack of parsing. In Unix you'd typically do this kind of thing with grep, but then you'd have to watch out that you don't accidently include the wrong rows because some other column happened to contain the string "alias" Try this: Get-Command | Out-GridView There's this thing called PowerGUI. It has a text editor for writing PS and a computer management GUI tool. It's written in PS itself. At first I wasn't too impressed, but then I noticed in the computer management thing there's an option to "view code". And then I saw how simple it is, how these nice interfaces were implemented with a trivial amount of PowerShell. Now I think PowerShell is great.
  • teh_klev 11y ago
    PowerGUI is a godsend. Sure PowerShell ISE ships for free, but PowerGUI is a much more capable editor/debugger. It's free as well.