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From: Herbert Xu <herbert@gondor.apana.org.au>
To: Gioele Barabucci <gioele@svario.it>
Cc: dash@vger.kernel.org
Subject: Re: Dash only reads the first character from pipe (bash reads whole line)
Date: Sat, 14 Nov 2015 18:51:22 +0800	[thread overview]
Message-ID: <20151114105122.GA17789@gondor.apana.org.au> (raw)
In-Reply-To: <n25ren$pf5$1@ger.gmane.org>

Gioele Barabucci <gioele@svario.it> wrote:
> 
> > The 'read' command seems to only read the first character and not the 
> > whole line.
> >
> > Example / comparison with bash:
> >
> > # /bin/dash
> > # sudo modprobe nf_conntrack
> > # read MAX </proc/sys/net/netfilter/nf_conntrack_max
> > # echo $MAX
> > 2
> >
> > # /bin/bash
> > # read MAX </proc/sys/net/netfilter/nf_conntrack_max
> > # echo $MAX
> > 262144
> 
> It this a known problem? Are there workarounds?

Yes it's a known problem, but arguably it's more of a kernel bug
than a dash bug (proc files cannot be read byte-by-byte).  You
can work around it using cat

MAX=$(cat /proc/.../file)

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

      reply	other threads:[~2015-11-14 10:51 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-11-13 23:24 Gioele Barabucci
2015-11-14 10:51 ` Herbert Xu [this message]

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