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Comment by vasilia | Hacker News Reader

> What about UNIX shells that allow to call public functions in dynamic libraries as if they were shell commands?

dlcall

> Or interact with running applications using the OS APIs like Powershell allows with WMI, COM, OLE Automation and .NET?

Depends what you need. You can use nc -U /var/run/socket or pipes with expect. If you have root permissions you can use gdb scripting/ebpf to communicate with user-space/kernel-space data of your application.

> Yes, there is DBUS, but isn't really integrated across the whole stack.

DBUS is a bus for desktops/mobile. I never saw that someone use it for server applications. The main idea(after KISS) of the Linux shell is that if you can't write something in awk it will be better to use python. Actually, in the Linux world, GRPC/REST is more common than OS-level API.

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So a couple of Linuxisms not portable across UNIX, which was my point.

Unix sockets and pipes are portable across all Unix(POSIX, because Linux is not Unix, but OS X is). Furthermore Unix sockets and pipes backwards compatible to 4.4BSD Unix or older OS.

Actually, this comparison is not correct. Windows and Unix have a different philosophy of kernel<->user level interaction. While Windows tries to add all functionality to the kernel, Unix does this on user level. Remember the KISS principle. So If you comfortable with Windows OS level API it's good for you, but for Unix world, it's not necessary to do something because we already have a different inter-process communication approach.

Which is why UNIX shells are a poor man's REPL quite far from what a Xerox inspired user/developer interaction aspired to achieve.

Pipe based interactions work properly only across CLI based applications, and even then the applications need to be explicitly written to accept and parse the data.

PowerShell or other Xerox inspired shells don't need kernel support to achieve their workflows.

> Which is why UNIX shells are a poor man's REPL quite far from what a Xerox inspired user/developer interaction aspired to achieve.

Unix shells are quite good for their purpose. It's not a full-featured programming language. Can you explain what is "poor man's REPL"?

> Pipe based interactions work properly only across CLI based applications

Yes. If you want to find something in logs or looking at any other text data pipes is a good solution. In any other case(like binary data) it will be better to choose GRPC(or any other RPC). I never have seen GUI apps on servers, sorry.

> PowerShell or other Xerox inspired shells don't need kernel support to achieve their workflows.

Good for them :)

A poor man's REPL is a shell that fails short of everything that was possible to do across the OS infrastructure with what Lisp/Smalltalk/Oberon/XDE/Cedar REPLs allowed to do.

An approximation of it would be to have a shell that is a Jupyter netbook with access to the whole set of OS APIs, shared libraries and applications, with the ability to jump into the debugger at any given step of the pipeline, and redo the current step.

I bet you saw GUI apps on UNIX workstations, though.

Then again, maybe Steve Jobs was right after all.

https://www.usenix.org/blog/vault-steve-jobs-keynotes-1987-u...

https://www.cake.co/conversations/rZXhqtP/that-time-i-had-st...

> A poor man's REPL is a shell that fails short of everything that was possible to do across the OS infrastructure with what Lisp/Smalltalk/Oberon/XDE/Cedar REPLs allowed to do.

Shell is a command-line interpreter with additional functionality like scripting. Why it should have fully functional REPL? Lisp/ST/etc are programming languages, they are uncomfortable for copying files, moving directories, calling curl or using tar.

> An approximation of it would be to have a shell that is a Jupyter netbook with access to the whole set of OS APIs, shared libraries and applications, with the ability to jump into the debugger at any given step of the pipeline, and redo the current step.

You can use python for this purpose. I don't understand why Unix shell should have all this functionality.

> I bet you saw GUI apps on UNIX workstations, though.

Yes, of course, I have GUI apps on my MacBook, but they don't use piping for inter-process communication because bi-directional pipes are not quite useful like an ordinary RPC.

> Shell is a command-line interpreter with additional functionality like scripting. Why it should have fully functional REPL? Lisp/ST/etc are programming languages, they are uncomfortable for copying files, moving directories, calling curl or using tar.

Lisp is an interactive programming language. On can run functions like COPY-FILE, RENAME-FILE, ...

The Listener of the Symbolics Lisp Machine has commands which allow prompting of arguments, input menus, completion, object reuse, etc. It's also integrated in Lisp. For example you can list a directory using a command and then use the pathname objects in calls to Lisp functions. One can also use the output of Lisp functions as input to commands. It's an interesting mix of a command interpreter and a Lisp REPL.

I guess we'll have to agree to disagree.

Nope. Your point was to argue personal preference as fact rather than simply accepting that some people like apples and others prefer oranges.

I get so utterly sick of stupid arguments where people compare their tools and then proceed to makes claims that one is objectively better than another when it’s clearly just a matter of personal taste

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