Hal wrote:

Could you create a pair of batch files that each set either 1) all, or 2) only the clashing, environment variables for MSC and Watcom?

Another pair of batch files could then be used to invoke one of these environment-setting pair and the desired compiler.

Yes indeed, it is not bad. Installing the compiler under XP appears to be mostly a matter of copying it, which I've already done. All the protected mode DLLs that are needed with DOS and earlier versions of windows are not needed under XP. Making batch files like you suggest would make eliminate the environment variable conflict with Watcom.

Does MSC stand for Microsoft C?

Yes. Jonathan and I use version 7.00, which is the last version that supported the various DOS memory models. You can't compile the DOS fractint with later Microsoft compilers. We did get it to work with Borland, and it's possible the current freely available Borland compiler will work. Open Watcom should work, but would take some effort to configure overlays. One reason Jonathan and I no longer have much help is that we have not let go entirely of the DOS version, and no one but us can compile it. However anyone with Linux can compile Xfractint, and maintenance on that platform probably usually ports easily back to DOS. Most other environments (e.g. Visual C) require massive code re- architecture. Paul Deleeuw and others has made a start at that. Tim