From mboxrd@z Thu Jan  1 00:00:00 1970
MIME-Version: 1.0
Date: Fri, 16 Oct 2009 17:58:04 +0200
Message-ID: <138575260910160858nfc9444fr73e3328d98eac98a@mail.gmail.com>
From: hugo rivera <uair00@gmail.com>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
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Subject: [9fans] dup(3)
Topicbox-Message-UUID: 8839560a-ead5-11e9-9d60-3106f5b1d025

I am having a hard time understanding the dircp script and the dup(3)
device. What's exactly the purpose of writing
@{builtin cd $1 && tar cf /fd/1 .} | @{builtin cd $2 && tar xTf /fd/0}
instead of
{builtin cd $1 && tar c .} | {builtin cd $2 && tar xT}
I also had a look to the pdf2ps script, and there, it seems to be
useful given that you must  provide a file trough the option
arguments. But for me this looks like a very narrow application for
the device. What other uses dup(3) might have?
Saludos

--
Hugo