From mboxrd@z Thu Jan  1 00:00:00 1970
From: random832@fastmail.com (Random832)
Date: Sun, 11 Sep 2016 18:13:19 -0400
Subject: [TUHS] Shell control through external commands
In-Reply-To: <20160911185053.GA901858@lisa.in-ulm.de>
References: <201609111739.u8BHd2pV146715@tahoe.cs.Dartmouth.EDU>
 <CAEoi9W62QMprW=AqXJ4aJuwxKnjydWfUgEpr7bRBQsWoc-gtkw@mail.gmail.com>
 <20160911185053.GA901858@lisa.in-ulm.de>
Message-ID: <1473631999.3825346.722456001.70CCA0C8@webmail.messagingengine.com>

On Sun, Sep 11, 2016, at 14:50, Sven Mascheck wrote:
> I tried to follow all the traces of #! and collected the results on
> http://www.in-ulm.de/~mascheck/various/shebang/
> I'd be happy to add and fix stuff, if somebody spots anything.

DEMOS (the soviet version of Unix) seems to have an independent
implementation that supports some features no-one else does

- use $* to define where the passed-in arguments [including the script
name] go between the interpreter-arguments specified on the #!-line
- alternate magic "/*#!"

I don't remember where I downloaded it from, I think maybe someone
posted it here a few years ago.

Relevant bits from sys1.c:

# define SCRMAG  "#!"
# define SCRMAG2 "/*#!"
# define ARGPLACE "$*"

     /* формат:
         пусть есть файл   /.../.../x
         со следующим содержимым:
         -------------------------------
         |#!CMD A1 A2 A3
         | .......

        Вызываем команду:
                x B1 B2

        Запустится на самом деле такая команда:
                CMD A1 A2 A3 /.../.../x B1 B2

        Один из аргументов Ai может иметь вид $*
        Тогда аргументы запуска подставятся на это место, а не в конец:
         -------------------------------
         |#!CMD A1 $* A2 A3
         | .......

        Вызываем:
                x B1 B2

        Запустится:
                CMD A1 /.../.../x B1 B2 A2 A3
     */

There's no comment describing the SCRMAG2 feature but you can see it
used in code:

        if (indir < NSYMLNK && u.u_offset > (off_t)2 ){
            cp = (char *) &u.u_exdata;
            if( !bcmp(cp, SCRMAG, 2 ))
                off = (off_t) 2;
            else if( u.u_offset > (off_t)4 && !bcmp( cp, SCRMAG2, 4))
                off = (off_t) 4;


Sole uses of these features in the source tree:

cmd/OPQRS/spline.c,v:@/*#!/bin/cc -O $* -o spline
cmd/EFGHIJK/glob.c,v:@/*#!/bin/cc -o glob