[TUHS] What was your "Aha, Unix!" moment?

[Larry McVoy]

On Fri, Oct 11, 2019 at 06:55:46AM +1000, Warren Toomey wrote:
> So I'll kick off another thread. What was your "ahah" moment when you
> first saw that Unix was special, especially compared to the systems you'd
> previously used?

Unix was pretty much the first thing I used.  I did regress to CPM Z80
based machine because 40-60 users on a 1Mhz (I think) VAX was crazy
slow, even though it had disk and I think 4MB of ram, the 128K 4mhz
z80 with floppies was faster.

I wrote assembly versions of ls, cp, mv, rm, etc - assembly so that 
I could cram the program into a 512 byte sector (both for speed of
loading as well as for small size).

The aha moment for me was one of the many times I was logged into
slovax (an 11/750 that had the BSD source on it) reading popen.c
and got to the point where it forked a process.  It blew my mind,
here I am in libc and it's creating processes for me.  I just didn't
expect that but was struck by the thought "huh, these Unix guys don't
fool around, they use the abstractions they advertise".

I expected something like Windows spawn or some VMS complex thing,
I sure as heck didn't expect fork and exec, shows how naive I was 
at the time.  Fun times.