Tavis Ormandy, a security researcher at Google, ported a Lotus 1-2-3 spreadsheet, released in 1988, three years before Linux itself, to run on Linux. The port is made on the basis of the processing of executable files for UNIX, found in the archive with warez on one of the BBS. The work of interest is that porting is done at the level of machine codes without the use of emulators or virtual machines. The result is an executable file that can run on Linux without any extra layers.
During porting, adaptation to the Linux system call interface was made, calls were redirected to glibc, incompatible functions were replaced, and an alternative driver for output to the terminal was integrated. The code also bypassed the license check, but Tavis owns a boxed copy of Lotus 1-2-3 for MS-DOS and has the legal right to use the product. The port is not Tavis' first attempt at running Lotus 1-2-3 on Linux, having previously provided a dedicated driver for DOSEMU to run a DOS version of Lotus 1-2-3 on modern terminals. You have now completed the task of running Lotus 1-2-3 on Linux without using an emulator.
Source: opennet.ru