Related request:
Issue 2102 – Reading password from a file
You can vote for it there.

Wouldn't using an environment variable be better and more flexible?

Yes, but this is only one EXAMPLE !!!
With this method, if the program you use writes directly to the PIPE, then nothing will be stored in the Task Manager. Some tools can work in this way.
Futhermore, if you need to execute the same using scripts only, then the solution is to write the password to a TEMP file and use the Get-Content command (similar to cat in Power Shell) to pass the content of the file to the WinSCP.exe.

Please, try to think about the improvement in the security with this simple alternative to send passwords to WinSCP.
Regards.

@Frongie: That way, you will see a process like this in the Task Manager:

This idea is good. The AnyDesk tool uses the same interface. Example:

So I suggest to implement this alternative to pass the password using the commandline.

OK. Thanks. We will see, if more people ask for this.

Sorry Martin!

1. KeePass is a Windows Graphical Application that implements the -pw-stin parameter.
   
2. Any Windows GUI Application can read from the console.
   

So, please check this:

• KeePass code (in C#) that reads the password from the console:
  https://github.com/dlech/KeePass2.x/blob/5ea1b24ad2c1b17b6d0017d68731c885af6b539d/KeePass/Util/KeyUtil.cs#L154
  
  
• How a Windows GUI App can use the Console:
  Adding Console I/O to a Win32 GUI App
  
  
• Microsoft examples about the use of the STDIN/STDOUT:
  https://learn.microsoft.com/en-us/dotnet/api/system.console.readline
  

Please, note that the current implementation for setting the password from another process that starts it the WinSCP it's VERY INSECURE. So, another alternative should be explored.

Regards.

I believe that GUI applications have no stdin.

Hi,

When using the current command line parameter

the password can be shown inside the "Command Line" column of the Task Manager.

So, I suggest to add the parameter "-pw-stdin" to read the password from a PIPE.
That's already implemented in the KeePass to hide password passed in the command line.
See it at: https://keepass.info/help/base/cmdline.html

I hope you agree to implement something similar.
Regards.