(29-11-2018, 11:08 AM)jkl Wrote: GNU sed and BSD sed are incompatible with each other. Which one is "the standard"?

They're incompatible with each others, but both are compatible with POSIX sed!
There is no "standard" tool. If you want to write a shell script using sed that would work on both GNU and BSD, then you have to limit yourself to what is defined in the paper above, be it the flag set, or syntax.

(29-11-2018, 11:08 AM)jkl Wrote: If we want modern standards, we should stop relying on both the dated POSIX standard and "Unix-like" operating systems. As POSIX is widely ignored today, why should we still endorse its environment which has major disadvantages on modern hardware which need to be worked around even four decades after its inception?

I think POSIX is still relevant today. I think it defines a sane base for OS development, on top of which it's easy to build, as it is not too restrictive.
The standard might even be too "loosy", because it only defines the minimal stuff needed, that would make programming strictly to it a bit too defensive and bothersome (be it in C, or though shell scripts).

(29-11-2018, 11:08 AM)jkl Wrote: Why do we still have to maintain our web servers over a text-based shell? Why do "modern" "Unix-like" systems still need to simulate ancient teletypes?

Text is still a good human-to-machine interface (IMO, better than sound for example, or pictograms), and POSIX defines its standards around this interface.
I must admit that sometimes, a GUI makes it easier for the human to work on, but as of today, when it comes to programming, it is still easier to make an application that is unrelated to any GUI, and then create the GUI around this tool (it also has the advantage to make it easier to script/automate).

I can't think of a good way to automate a GUI, and automating a voice-based interface would make conditional fairly complex use cases IMO.

What would your perfect interface be like?