Newsgroups: comp.os.msdos.programmer
Path: utzoo!utgpu!watserv1!broehl
From: broehl@watserv1.waterloo.edu (Bernie Roehl)
Subject: Re: "file cannot be copied onto itself"
Message-ID: <1990Oct3.204656.941@watserv1.waterloo.edu>
Organization: University of Waterloo
References: <2091@nyx.UUCP> <1213@crpmks.UUCP>
Date: Wed, 3 Oct 90 20:46:56 GMT
Lines: 15

In article <1213@crpmks.UUCP> billb@crpmks.UUCP (Bill Bochnik (Info Systems)) writes:
>
>>How does the DOS "copy" command know when the source and destination file are
>>one in the same (i.e., "file cannot be copied onto itself")?  I can't believe
>>that it's just a string compare. The logistics of that are pretty awkward.

I suspect that it first fully resolves the name, checks to see they're on the
same drive, then finds what their starting FAT entries are.  (Sort of like
seeing if two directory entries point to the same inode on Unix).

-- 
	Bernie Roehl, University of Waterloo Electrical Engineering Dept
	Mail: broehl@watserv1.waterloo.edu OR broehl@watserv1.UWaterloo.ca
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