Path: utzoo!attcan!uunet!lll-winken!ames!ucsd!rutgers!bellcore!faline!thumper!ulysses!andante!alice!debra
From: debra@alice.UUCP (Paul De Bra)
Newsgroups: comp.unix.wizards
Subject: Re: Black hole file
Message-ID: <8776@alice.UUCP>
Date: 16 Jan 89 16:07:50 GMT
References: <498@sdrc.UUCP>
Reply-To: debra@alice.UUCP ()
Organization: AT&T, Bell Labs
Lines: 27

In article <498@sdrc.UUCP> scjones@sdrc.UUCP (Larry Jones) writes:
}OK, I've got one for you guys.  I've got this file that just
}absorbs whatever get put into it.  For example, if I do:
}
}	ls -l >blackhole ; cat blackhole
}
}I get nothing.  ls -l blackhole shows it has a reasonable size,
}but even od just shows a few zeros.  If I do this with a
}different file, it works like you would expect.  If I delete
}blackhole and try it again, I get the same results (I also get
}the same inode for the file, which I suspect is critical).
}
Sounds like you have a brain-damaged shell that treats "blackhole"
as a name for /dev/null.
If you do "ls -l >/dev/null ; cat /dev/null" you get nothing.
ls -l /dev/null shows a reasonable size because /dev/null is a character
device and the "size" field is actually the minor device number and
not the size.
The suspicious part is that when you remove blackhole and try again you
get the same result. This makes me believe your shell does something
magic (i.e. stupid) with the name blackhole.

Paul.
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