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From: chet@odin.INS.CWRU.Edu (Chet Ramey)
Newsgroups: comp.unix.questions
Subject: Re: redirect stdin in k/sh ?
Message-ID: <1991Feb11.220203.2872@usenet.ins.cwru.edu>
Date: 11 Feb 91 22:02:03 GMT
References: <1991Feb10.201058.22238@noose.ecn.purdue.edu>
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Organization: Case Western Reserve Univ. Cleveland, Ohio, (USA)
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>What's the difference between the following two ways in handling
>stdin in k/sh ?
>
>	foo </dev/null

This means that foo sees stdin (file descriptor 0) as a valid file
descriptor, but one that returns EOF (read returns 0) on first read. 

>vs.
>	foo <&-

foo sees its file descriptor 0 as closed, which means that reads on fd
0 return -1 with errno set to EBADF.

Chet
-- 
Chet Ramey				``There's just no surf in
Network Services Group			  Cleveland, U.S.A. ...''
Case Western Reserve University
chet@ins.CWRU.Edu		My opinions are just those, and mine alone.