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From: jbayer@ispi.UUCP (Jonathan Bayer)
Newsgroups: comp.unix.questions,comp.unix.xenix
Subject: Re: How to determine file being redirected to in C
Keywords: redirection
Message-ID: <478@ispi.UUCP>
Date: 2 Mar 89 13:15:20 GMT
References: <10@sherpa.UUCP> <475@ispi.UUCP> <1105@auspex.UUCP>
Reply-To: jbayer@ispi.UUCP (Jonathan Bayer)
Distribution: na
Organization: Intelligent Software Products, Inc.
Lines: 22

In article <1105@auspex.UUCP> guy@auspex.UUCP (Guy Harris) writes:
}
} }Use the stat() and fstat() functions, then compare the inode numbers 
} }in the structure.  If they are the same then the two files are identical.
}
}Wrong.  If the inode numbers (st_ino) *AND* the file system IDs (st_dev)
}are the same, then the two files are identical.  If just the inode
}numbers are the same, you can't conclude anything about whether the
}files are the same or not.  They could have the same inode number but be
}on two different file systems; inode numbers are *not* unique across
}file systems.

I stand corrected.  Working on one filesystem for a while tends to make
one forget that the inodes can come from multiple filesystems.


JB
-- 
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