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From: Jeff King <peff@peff.net>
To: Junio C Hamano <gitster@pobox.com>
Cc: Michael J Gruber <git@drmicha.warpmail.net>,
	Git Mailing List <git@vger.kernel.org>
Subject: Re: POSIX woes in t7810.87: dash bash or bash dash?
Date: Mon, 20 Jun 2011 20:21:14 -0400	[thread overview]
Message-ID: <20110621002114.GA2050@sigill.intra.peff.net> (raw)
In-Reply-To: <7vwrgg9j1n.fsf@alter.siamese.dyndns.org>

On Mon, Jun 20, 2011 at 04:31:32PM -0700, Junio C Hamano wrote:

> >> +	cat >expected <<-EOF &&
> >> +	hello.c:	printf("Hello world.\n");
> >> +	EOF
> >
> > Do you need to quote EOF to suppress expansion in the here document?
> > Both bash and dash seem to pass unknown backslash-escapes like "\n"
> > through unharmed, but I don't know if that is portable (they do both
> > munge known escapes like "\\", of course).
> 
> I do not think that is strictly necessary, as we are not in the corner of
> non-portable echo behaviour anymore, but I guess it wouldn't hurt.

I think my brain is fried from using too many almost-shell-compatible
quoting languages. For example, unknown escape sequences in C get their
backslash removed and the sequence used literally (at least by gcc; I
couldn't find anything definite in C99 on this).

But actually, POSIX is quite clear that a backslash before anything
besides:

  $   `   "   \   <newline>

is just a backslash, and gets included literally.

-Peff

      reply	other threads:[~2011-06-21  0:21 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-06-20  9:58 POSIX woes in t7810.87: dash bash or bash dash? Michael J Gruber
2011-06-20 11:04 ` Jonathan Nieder
2011-06-20 17:13   ` Jeff King
2011-06-20 21:46 ` Junio C Hamano
2011-06-20 23:24   ` Jeff King
2011-06-20 23:31     ` Junio C Hamano
2011-06-21  0:21       ` Jeff King [this message]

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