TROSuperTCPChannel and Linux with Delphi 12.1 - Cannot connect to anything

Recently upgraded our console app style code to Delphi 12.1 and the latest RemObjects Remoting SDK.

On Centos 7, TROSuperTCPChannel can no longer establish a connection to local host or anywhere else. EROSuperChannelException - No connection available.
Changing from TROSuperTCPChannel to TROIndySuperTCPChannel the exact same code works. We’ve built out a standalone test app using a new Delphi 12.1 project and this is reproducible.

Logged as bugs://D19466.

bugs://D19466 was closed as fixed.


  • update uROSocket.pas as
function TROSocket.CanRead(aTimeout: Integer): Boolean;
  l_result := RO_Select(fSocket + 1, @l_fdSet, nil, nil, l_pTimeVal); //<<<changed
  • close Delphi IDE
  • launch C:\Program Files (x86)\RemObjects Software\Build\install_DA.cmd (or install_RO.cmd) with admin rights for rebuilding .dcu & .bpl

Appreciate the speedy update, but remember those test servers and testing framework I mentioned needed to be in place for Linux maybe 5 years ago… still clearly not in place.


Linux support was broken in .1591 build.