I'm building a tool which searches for and opens Delphi source files. Until now execution was a simple ShellExecute call to the .pas file and everything was working just file. Now, as a second Delphi version is introduced I had to change the code to support opening said file in a specific Delphi version. My issue is that a simple call to bds.exe will always launch a new Delphi instance, and I need to re-use the one currently running. Basically I need to mimic the IDEs behavior when double-clicking a .pas file in Explorer.   Unfortunately I could not find any documentation about the parameters of BDSLauncher, nor any relevant parameters of Bds.exe which could achieve this. I also built a small program which only lists the parameters it was started with and temporarily replaced BdsLauncher.exe and then bds.exe to see what it received when something is double-clicked, but all I got was the full path of bds.exe.   Can anyone point me to the right direction?   Thanks!