The Free Pascal software distribution includes a FLOSS look-alike of Borland's character-mode IDE for Pascal. If you can track down RHIDE, that's a similar look-alike IDE that runs in MS-DOS (it does require 386+ since it uses a DOS extender) and compiles C/C++ using gcc. (One version of it is distributed as part of the FreeDOS "development" packages.) It would be nice to recreate a broadly similar look and featureset starting from a modern text-mode editor such as the newly released MS-EDIT, aiming for modern IDE infrastructure like LSP and DAP. Such a project may find quite some use for, e.g. remote system administration tasks using ssh.