en-US/about_PSeudo.help.txt
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about_PSeudo SHORT DESCRIPTION General information about PSeudo. LONG DESCRIPTION PowerShell doesn't have an analog to sudo from the *nix world. This means that if we want to execute commands with elevated privileges - ie, as Administrator - that we need to spawn a child PowerShell process with the `-Verb` parameter set to `RunAs`. This process will have elevated privileges, if the user agrees to it. Typically, when executing commands in a child PowerShell process, everything works the way we would like it to - the subshell is spawned, our commands (either in string or script block format) are executed in the subshell, and the results are printed back in the host terminal. However, this is not the case for Administrator processes. In these situations, the child PowerShell process spawns a separate window, logs its output to that window, and then typically exits when the script terminates. Any IO and feedback that happens in that process, regardless of whether it's the output stream, the error stream or otherwise, is lost into the aether. This is further complicated by the fact that we typically don't want end users to see the Administrator window - it looks sloppy. This can be mitigated by keeping the Administrator window open after the command has terminated, but this makes for a bad user experience. PSeudo solves this problem with a combination of named pipes and .NET's serialization framework. It exposes a function called Invoke-AsAdministrator that spawns a child Administrator process, serializing its arguments and embedding them into a string -Command. This process then creates a named pipe and sends serialized results back to the host process. In addition to handling basic output streams, PSeudo can also capture and handle calls to other output functions, such as Write-Error, Write-Verbose and Write-Progress. It does this by defining aliases for these commands that resolve to functions defined inside of the Administrator process's scope. This allows us to execute commands in an Administrator-level process and have the output print in the host terminal in an entirely seamless fashion, "just like sudo". Make no mistake: This approach is extremely cursed. Many of the obvious kinks have been worked out and it has fairly comprehensive tests, but it's very likely that there are subtle bugs and unforeseen edge cases. As usual, be careful when working with elevated privileges and untrusted input. You've been warned. |