As someone else mentioned, MS seems finally to have approached the state of 1975 Unix (or maybe 1983, with Korn shell). I have to add ZCPR for Z80 based 8 bit systems. If I recall correctly, it had a passable imitation of the Unix shell, common utilities, and I think pipes, subject to the limitations of an 8 bit CPU, 64K memory, and lack of multitasking. I saw nothing better until I started playing with Minix 1 as part of a grad school class, and then found a used copy of IBM Xenix 1.0 at an amateur radio flea market. The last saved me a lot of time when learning to handle C pointers and references without the need to reboot at every mistake.