Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!wuarchive!emory!gatech!bloom-beacon!eru!hagbard!sunic!mcsun!ukc!stc!stl!robobar!ronald
From: ronald@robobar.co.uk (Ronald S H Khoo)
Newsgroups: comp.unix.questions
Subject: Re: #! loader convention
Message-ID: <1991Apr18.084943.17845@robobar.co.uk>
Date: 18 Apr 91 08:49:43 GMT
References: <1991Apr15.232541.23205@beaver.cs.washington.edu> <15865@smoke.brl.mil>
Organization: Robobar Ltd., Perivale, Middx., ENGLAND.
Lines: 22

gwyn@smoke.brl.mil (Doug Gwyn) writes:

> pauld@cs.washington.edu (Paul Barton-Davis) writes:
> >I believe that the convention of interpreting #! comments in
> >"scripts" is built in the loader for BSD. Does anyone know
> >if any such mechanism exists at the same level in System V ?

> It's handled by code in the kernel (part of the exec() system call).
> SVR4 is supposed to support this.

And if you're running System V releases previous to 4, you can
get *some* of the functionality of #! by using a shell that
emulates it for you, e.g. ash (comp.sources.unix archives somewhere).

And, for at least some of the csh's that some System V(<R4) vendors
provide, you can say set shell=/usr/bin/perl to get if you also have a
reasonably recent perl.

But doing this sort of thing does lead to a rather inconsistent system,
so I don't recommend it.
-- 
Ronald Khoo <ronald@robobar.co.uk> +44 81 991 1142 (O) +44 71 229 7741 (H)