libtool-patches
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: sed and limited record length


From: Ralf Wildenhues
Subject: Re: sed and limited record length
Date: Mon, 22 May 2006 13:22:26 +0200
User-agent: Mutt/1.5.11

Hi Gary,

* Gary V. Vaughan wrote on Mon, May 22, 2006 at 01:07:19PM CEST:
> Ralf Wildenhues wrote:
> >* Gary V. Vaughan wrote on Mon, May 22, 2006 at 11:45:01AM CEST:
> >>
> >>foo=`echo X"$bar " | $SP2NL | $Xsed -e baz | $NL2SP`

> >that will still be the case, after
> >                                             | $NL2SP
> >
> >it will be space-space.  Then, the shell is to rip off the final
> >newline, if any.
> 
> That part was deliberate on my part; I thought you were worried that
> for some implementations of $Xsed input that didn't end with a NL
> would be problematic...

Yes.  But in above sequence, that can't be the case.  I think we've
clarified this now.

> > My point is that some shells may be confused iff
> >there is no final newline.  That's what the ($NL2SP; echo) would be for.
> >
> >I simply don't know whether that is necessary for some broken shells.
> 
> ...but you are worried that there are shells that don't like backtick
> substitutions that don't end with a newline?  I would be amazed if
> such a shell could even come close to being able to run a typical
> configure script. 

I would be, too.  But given how some old shells implement quoting
internally (8bit stuff and the like), I wouldn't be too surprised
if they were "interesting" wrt. backtick expansion, too.

In fact, there is a "modern" system which has had issues in this
regard: MinGW (and I assume Cygwin) have at times failed to strip
the \r from a \r\n ending in such an expansion.  The libtool.m4
code witnesses this at several points, somewhat inconsistently.

> Or do you mean there are shells where the later
> ``eval $bar'' will fail without a trailing newline?

I hope not.

Cheers,
Ralf




reply via email to

[Prev in Thread] Current Thread [Next in Thread]