[fpc-devel] Compiler message colour scheme

[Tomas Hajny]

On 2020-11-25 10:31, Nikolai Zhubr via fpc-devel wrote:
> 25.11.2020 1:52, Tomas Hajny via fpc-devel:




Hi Nikolai,

>> No problem, thanks for testing. Unfortunately, it doesn't work for me
>> under Windows (Win 10 Pro 64-bit) either with the original version or
> 
> Have you also checked with this registry trick for win10:
> 
> [HKEY_CURRENT_USER\Console]
> "VirtualTerminalLevel"=dword:00000001
> 
> (As per https://superuser.com/a/1300251/109090)
  .
  .

If I read the article correctly, it says that an application may enable 
this processing explicitly using SetConsoleMode, or that it may be 
enabled for all applications / consoles using the mentioned registry 
key. The code added to the compiler contains the mentioned 
SetConsoleMode setting, thus it should be sufficient according to the 
article. However, the call fails (here) with error 87 (invalid 
parameter). And btw, changing the registry key doesn't help (i.e. I 
still get the same error). The same call (SetConsoleMode) performed 
without setting the respective flag (ENABLE_VIRTUAL_TERMINAL_PROCESSING) 
succeeds. I'm willing to have a look at additional hints, but I won't 
perform additional research myself for this.

For anybody interested, the following test program reproduces the 
functionality in the compiler (and provides debug information):

-----------------------------
{$MODE OBJFPC}
uses
  Windows;
const
   ENABLE_VIRTUAL_TERMINAL_PROCESSING = $0004;
   CachedIsATTY : Boolean = false;
   IsATTYValue : Boolean = false;

function IsATTY(var t : text) : Boolean;
   const dwMode: dword = 0;
   begin
     if not(CachedIsATTY) then
       begin
         IsATTYValue := false;
         if GetConsoleMode(TextRec(t).handle, dwMode) then
         begin
           WriteLn ('dwMode = ', dwMode);
           if not (SetConsoleMode(TextRec(t).handle, dwMode)) then
            WriteLn ('SCM0: ', GetLastError);
           dwMode := dwMode or ENABLE_VIRTUAL_TERMINAL_PROCESSING;
           if SetConsoleMode(TextRec(t).handle, dwMode) then
             IsATTYValue := true
           else
            WriteLn ('SCM: ', GetLastError);
         end
          else
           WriteLn ('GCM: ', GetLastError);
         CachedIsATTY:=true;
       end;
     Result:=IsATTYValue;
   end;

begin
  WriteLn (IsATTY (Output));
end.
======================================

I get the following result (regardless from the registry setting):

dwMode = 3
SCM: 87
FALSE

Tomas