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From: arisawa@ar.aichi-u.ac.jp
To: Fans of the OS Plan 9 from Bell Labs <9fans@cse.psu.edu>
Subject: Re: [9fans] Environment variable
Date: Wed,  9 Aug 2006 20:16:34 +0900	[thread overview]
Message-ID: <00A70127-4D3A-4598-ABCD-29EBEB74B183@ar.aichi-u.ac.jp> (raw)
In-Reply-To: <20060809110352.GA5077@shodan.homeunix.net>

Thanks Martin,

Then, how to bring up an environment variable a to a shell variable b?
command
b=`{cat /env/a}
does not work all the time.

On 2006/08/09, at 20:03, Martin Neubauer wrote:

> Hello,
>
> I don't think that this really is weird. My understanding is that
> the terminating '\0' is not treated as part of the content of a
> string but merely of its representation in memory. So if you output
> a null string, you don't actually output anything (and therefore
> assign nothing to $b). That then explains why xd fails to open $a
> (which is an actual string, albeit with length zero) and waits for
> standard input because $b isn't expanded to anything.
>
> I hope my attempt at an explanation wasn't utter nonsense and helped
> clarifying a bit.
>
> Regards,
>    Martin



  reply	other threads:[~2006-08-09 11:16 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-08-04  9:37 [9fans] vmware? Anssi Porttikivi
2006-08-04  9:47 ` Lluís Batlle i Rossell
2006-08-04 15:15   ` Richard Bilson
2006-08-04 15:44     ` erik quanstrom
2006-08-07 22:14       ` Richard Bilson
2006-08-07 23:50         ` Federico Benavento
2006-08-04 19:03     ` Gorka guardiola
2006-08-09 10:00       ` [9fans] Environment variable arisawa
2006-08-09 11:03         ` Martin Neubauer
2006-08-09 11:16           ` arisawa [this message]
2006-08-09 11:27             ` Martin Neubauer
2006-08-09 11:36               ` arisawa
2006-08-09 11:39               ` Martin Neubauer
2006-08-09 12:04                 ` arisawa
2006-08-09 12:26                   ` Martin Neubauer
2006-08-09 12:39                     ` Martin Neubauer
2006-08-09 12:58                       ` arisawa
2006-08-09 13:22                         ` arisawa
2006-08-09 13:30                         ` Martin Neubauer
2006-08-10  2:15                         ` erik quanstrom
2006-08-09 12:03               ` [9fans] editor, man/less, dns setup, screen setup bituman
2006-08-09 12:08                 ` Martin Neubauer
2006-08-09 12:08                 ` Robert Raschke
2006-08-19  0:45                   ` Rodolfo (kix)
2006-08-10  2:09         ` [9fans] Environment variable erik quanstrom

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