Having Powershell Autofill command line prompt - powershell

Question

There is an old command line tool my company uses to deploy log files to various servers.... whoever wrote it made it very very repetitive.
There is a lot of prompting that happens and I want to automate this process. We have a long term goal of replacing this .exe file down the line but for now automation works for the short term..
Example
./logdeploy.exe
Enter the destination folder:
I would like the powershell script to just automatically enter the folder, since its literally the same folder. because this exe is going to ask for it at least 20 times throughout this process, so copy paste just gets anyoing.
Is this even possible to do?

Answer 1

If there really is no way around simulating interactive user input in order to automate your external program, a solution is possible under the following assumption:
Your external program reads interactive responses from stdin (the standard input stream).
While doing so is typical, it's conceivable that a given program's security-sensitive prompts such as for passwords deliberately accept input from the terminal only, as so to expressly prevent automating responses.
If the first assumption holds, the specific method that must be used to send the response strings via stdin depends on whether the external program clears the keyboard buffer before each prompt.
(a) If it does not, you can simply send all strings in a single operation.
(b) If it does, you need to insert delays between sending the individual strings, so as to ensure that input is only sent when the external program is actively prompting for input.
This approach is inherently brittle, because in the absence of being able to detect when the external program is read to read a prompt response, you have to guess how much time needs to elapse between sending responses - and that time may vary based on many runtime conditions.
It's best to use longer delays for better reliability, which, however, results in increased runtime overall.
Implementation of (a):
As zett42 and Mathias R. Jessen suggest, use the following to send strings C:\foo and somepass 20 times to your external program's stdin stream:
('C:\foo', 'somepass') * 20 | ./logdeploy.exe
Again, this assumes that ./logdeploy.exe buffers keyboard input it receives before it puts up the next prompt.
Implementation of (b):
Note: The following works in PowerShell (Core) 7+ only, because only there is command output being sent to an external program properly streamed (sent line by line, as it becomes available); unfortunately, Windows PowerShell collects all output first.
# PowerShell 7+ only
# Adjust the Start-Sleep intervals as needed.
1..20 | ForEach-Object {
Start-Sleep 1
'C:\foo'
Start-Sleep 2
'somepass'
} | ./logdeploy.exe