VT sequences to "CONOUT$" vs. STD_OUTPUT_HANDLE

[vefatica]

What's the difference? Are there situations where one will fail and the other work? I have been using a "CONOUT$" handle in pretty straightforward console apps (some specifically for WT) and I haven't run into any problems.

[lhecker]

You can find more information about this here: https://learn.microsoft.com/en-us/windows/console/console-handles
Specifically:

The CreateFile function enables a process to get a handle to its console's input buffer and active screen buffer, even if STDIN and STDOUT have been redirected. To open a handle to a console's input buffer, specify the CONIN$ value in a call to CreateFile. Specify the CONOUT$ value in a call to CreateFile to open a handle to a console's active screen buffer.

In other words, CreateFile("CONOUT$") always writes directly into the terminal. If you run myapp.exe > output.txt to write your output into a file, the file will remain empty and the text will still appear in the terminal. That's why I think most of the time you probably want to use GetStdHandle(STD_OUTPUT_HANDLE) instead.

[determin1st]

as i understand reading through documentation, with CONOUT$ one can do asynchronous writes, which are impossible with STDOUT handle obtained with GetStdHandle. if asynchronity isnt possible, the WriteFileEx will say "incorrect descriptor" and WriteFile will not return instantly with 0 result but write synchronously