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From: raible@orville.nas.nasa.gov (Eric Raible)
Newsgroups: comp.lang.lisp
Subject: Re: exploratory system for unix system calls/facilities
Message-ID: <3514@amelia.nas.nasa.gov>
Date: 20 Oct 89 20:59:14 GMT
References: <1753@xyzzy.UUCP> <4139@hplabsz.HPL.HP.COM>
Sender: news@amelia.nas.nasa.gov
Reply-To: raible@orville.nas.nasa.gov (Eric Raible)
Organization: NASA Ames Research Center, Moffett Field, CA
Lines: 33

In article <4139@hplabsz.HPL.HP.COM> mayer@hplabs.hp.com (Niels Mayer) writes:
>In article <1753@xyzzy.UUCP> kan@tom.dg.com () writes:
>>Does anyone know of an interactive environment for playing around with
>>all those wonderful Unix system calls?
>>
>>I guess what I'd like is something that will let me try things out without 
>>having to write/compile/debug C code.  For example, a simple client/server 
>>using shared memory, semaphores, etc. implemented in a few Lisp expressions 
>>would run in a couple of terminals (or windows).
>>Doing this junk in C, needless to say, is a real pain in the butt.
>
>I'd certainly be interested in getting any enhancements to xlisp for
>supporting some of the uglier aspects of unix hacking in a cleaner fashion.

I've built something along these lines for xscheme, but I'm sure that
it could easily be adapted for xlisp.

Before I explain it, here are some examples:

(define (system string) (%call-c-function 'system string))
(%call-c-function 'printf "%s%d%c" (symbol->string 'eric) 10 #\newline)

%call-c-function gets the address using nlist (it also caches it on
the plist of the name of the function for speed), and then calls the
C function with the "C" values of each of the arguments.

Of coure argument checking could easily be added, but I haven't had the
need.  Presently %call-c-function returns only integers, but that could
also be easily added.

Mail me if you want the code.

- Eric (raible@orville.nas.nasa.gov)