The QNX shell could easily do remote execution. I worked at a company in the mid-90s (porting Unix software to QNX). My machine had a modem on it, and my boss

The QNX shell could easily do remote execution. I worked at a company in the mid-90s (porting Unix software to QNX). My machine had a modem on it, and my boss (the owner of the company) would use it from his computer to dial out---all he had to do was reference the modem device on my computer at his command line. In fact, you could run a program on a local machine referencing a file on a second machine, pipe the output to a program on a third machine and have that redirect the output to a file on a fourth machine, all from the command line. I don't recall the exact syntax, but it was something like: cat @2/path/to/large/file | @3/bin/grep 'foo' >@4/tmp/output (Individual hosts were numbered on a QNX ethernet based network, but the default permmissions were Unix like). All of this was a consequence of the message-based QNX operating system (whether messages were delivered locally or remotely was invisible to programs) but I don't see why something like can't be done today.