Bart Oldeman

DOSEMU (1992) and FreeDOS (1994) are long-running projects which allow you to run DOS applications on Linux and on bare hardware. I will describe their history and current developments. Intended audience: anyone who is interested in DOS and emulation.

I will describe past and current developments relating to DOSEMU and FreeDOS. This includes: * The Dosemu2 project, a continuation of DOSEMU coordinated by Stas Sergeev. * Where does DOSEMU fit in among other solutions such as DOSBOX and QEMU? * Use of KVM within Dosemu2 to allow running DOS applications at near-native hardware speed on CPUs that no longer support the vm86() syscall. * FreeDOS 1.2 and an outlook to FreeDOS 2.0. * The GCC IA-16 port with support for far pointers by Rask Ingemann Lambertsen, Andrew Jenner and TK Chia. This finally allows us to compile FreeDOS components using a Free compiler, instead of Open Watcom which has more restrictive licensing terms.

One of the challenges in HPC is to deliver a consistent software stack that balances the needs of the system administrators with the needs of the users. This means running recent software on enterprise Linux distributions that ship older software. Traditionally this is accomplished using environment modules, that change environment variables such as $PATH to point to the software that is needed. At Compute Canada we have taken this further by distributing a complete user-level software stack, including all needed libraries including the GNU C library, but excluding any privileged components. I will describe our setup, which combines Nix for the bottom layer of base components, EasyBuild for the top layer of more scientifically inclined components, Lmod to implement environment modules, and the CernVM File System (CVMFS) to distribute it to Canadian supercomputers. Expected prior knowledge: knowing how to use the command line and environment variables.