RE: binfmt_script and ^M

From: Laramie Leavitt (laramie.leavitt@btinternet.com)
Date: Tue Mar 06 2001 - 09:45:51 EST


> Andreas Schwab wrote:
> > Paul Flinders <paul@dawa.demon.co.uk> writes:
> > |> Andreas Schwab wrote:
> > |>
> > |> > This [isspace('\r') == 1] has no significance here. The
> right thing to
> > |>
> > |> > look at is $IFS, which does not contain \r by default.
> The shell only splits
> > |>
> > |> > words by "IFS whitespace", and the kernel should be
> consistent with it:
> > |> >
> > |> > $ echo -e 'ls foo\r' | sh
> > |> > ls: foo: No such file or directory
> > |>
> > |> The problem with that argument is that #!<interpreter> can be applied
> > |> to more than just shells which understand $IFS, so which environment
> > |> variable does the kernel pick?
> >
> > The kernel should use the same default value of IFS as the Bourne shell,
> > ie. the same value you'll get with /bin/sh -c 'echo "$IFS"'. This is
> > independent of any settings in the environment.
> >
> > |> It's a difficult one - logically white space should
> terminate the interpreter
> >
> > No, IFS-whitespace delimits arguments in the Bourne shell.
>
> Way back whenever processing #! was moved from the
> shell to the kernel** this argument would have made sense -
> today I'm not so sure.
>
> But I'm quite happy for the kernel to use just space and
> tab if it wishes, or anything else for that matter but it _is_
> confusing that the error code doesn't distinguish problems
> with the script from problems with the interpreter.
>
> **Did linux ever rely on the shell for this?

Maybe the correct answer would be to create a proc entry for this.
That allow the user to decide what is whitespace on his machine,
since nobody here appears to agree.

User: hmm... Wonder what happes if i do the following
       %cat '$#! \n\t\r' > /proc/whitespace
later, % config.sh : Error file not found.
Oops, bug report... ;-)

Laramie

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This archive was generated by hypermail 2b29 : Wed Mar 07 2001 - 21:00:19 EST