Re: [RFC/PATCH] t0081-*.sh: Fix failure of the 'long read' tests

From: Jeff King <peff@peff.net>
Date: Apr 26, 2011, 23:48 UTC
Message-ID: <20110426234850.GC32491@sigill.intra.peff.net>
In-Reply-To: <4DB70972.20308@ramsay1.demon.co.uk>

On Tue, Apr 26, 2011 at 07:05:38PM +0100, Ramsay Jones wrote:

Show 11 quoted lines

> The infinite loop is caused by the loop variable increment
> expression, which looks something like this:
> 
>     : $((i = $i + 1)) || return
>
> [...]
>
> The reason for the RFC is that I don't understand why (apparently)
> I'm the only person seeing this failure; I suspect that a newer
> version of bash than I have does not have this problem (ie the
> original arithmetic expansion actually works). dunno :-(

Yeah, that syntax is handled just fine by my bash and dash:

  $ cat >foo.sh <<'EOF'
  i=1
  : $((i = $i + 1))
  echo $i
  EOF

  $ bash foo.sh
  2
  $ bash --version | head -n 1
  GNU bash, version 4.1.5(1)-release (x86_64-pc-linux-gnu)

  $ dash foo.sh
  2

But I think your i=$(($i + 1)) is the right solution.

-Peff