Maybe I am missing some context here, but are we talking about AMIX or AmigaOS? I am asking because the latter never looked particularly UNIX-like to me. But maybe that's because I never worked with MS-DOS, so, being only familiar with Linux, Windows, and AmigaOS, I might be overestimating the difference between UNIX and AmigaOS.

Edit: btw, the AmigaDOS developers manual says that there was also a cross compiler (and serial transfer tool) for MS-DOS. I am wondering whether anybody every used that.