DOS Subsystem for Linux

A WSL alternative for users who prefer an MS-DOS environment. DOS Subsystem for Linux integrates a real Linux environment into MS-DOS systems, allowing users to make use of both DOS and Linux applications from the DOS command prompt.

Building

• doslinux depends on several packages.

In Fedora 38, run

sudo dnf install wget git patch bzip2 gcc glibc glibc-static g++ libstdc++ libstdc++-static make binutils flex bison openssl-devel mtools nasm zip unzip bc

In Ubuntu 22.04, run

sudo apt install build-essential git gcc make nano flex bison libssl-dev mtools nasm zip unzip bc

In a VM configured for 16 CPUs, 16GB RAM, hosted on a dual Intel Xeon E5-2680 v4 2.4GHz hypervisor (a 9 year old server in 2023), full builds take about 10-15 miniutes and will consume about 4GB of disk space.

• The included Makefile will download gcc, binutils, busybox (1.35.0), and https://github.com/richfelker/musl-cross-make for you.

• The included Makefile will then build a i386-linux-musl cross-compiler and Linux 5.8.9 kernel for you.

• Adjust the variables at the top of Makefile if you would like to use a higher/lower $(ARCH) or different kernel. (NOTE: this isn't quite working correctly yet)

• Running make is an alias for make dist which will result in a DSLxxxB.ZIP file containing doslinux, init, a Linux bzImage kernel, and busybox.

• After the completion of building the cross-compiler, sudo make -j$(CORES) install is executed to put the cross-compiler toolchain in your /usr/local/ path.

• You can unzip a roughly 6.5MB DSLxxxB.ZIP zipfile onto a DOS system, like MS-DOS or FreeDOS, and then start doslinux by running a command like C:\DOSLINUX\dsl or C:\DOSLINUX\dsl sh (giving you a shell into the loaded Linux).

• Also try running make help, make showconfig if you run into configuration issues.

• Run make clean to clean up the local git repo. Run make ultraclean to also get rid of the installation of the cross compiler toolchain in /usr/local.

Old Build Instructions

• You will need a cross toolchain targeting i386-linux-musl on PATH.

  https://github.com/richfelker/musl-cross-make is a tool that can build one for you with minimal hassle. Set TARGET to i386-linux-musl.

• Build the prequisites (Linux and Busybox) by running J=xxx script/build-prereq, replacing xxx with the desired build parallelism.

• You will need a hard drive image hdd.base.img with an installed copy of MS-DOS on the first partition.

• Run make

  This will produce a new hard drive image hdd.img with DOS Subsystem for Linux installed. Invoke C:\doslinux\dsl <command> to run Linux commands. C:\doslinux can also be placed on your DOS PATH for greater convenience.