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From: munnari!stcns3.stc.oz.AU!dave@uunet.UU.NET (Dave Horsfall)
Newsgroups: comp.virus
Subject: Write protect tabs (was Re: CRC's)
Message-ID: <0003.8911171251.AA11880@ge.sei.cmu.edu>
Date: 15 Nov 89 01:14:28 GMT
Article-I.D.: ge.0003.8911171251.AA11880
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In article <0007.8911071214.AA17820@ge.sei.cmu.edu>,
    kichler@harris.cis.ksu.edu (Charles Kichler) writes:

| The advantage is hardware is difficult to modify via software.  As of yet,
| I haven't seen a program that can beat a write protect tab.

I have heard a story, perhaps apocryphal, of a disk controller whose
"write protect" mechanism merely set a bit in a register, which the
software was supposed to check.

Do you _know_ your write-protect tab really works?

[Ed. This question was discussed a few times on VIRUS-L/comp.virus;
the consensus was (after reviewing schematic diagrams) that the write
protect mechanism on PCs (and clones thereof) and Macs is implemented
in hardware and is thus not circumventable without hardware
modifications.  Unless someone can produce a definitive, reproducable
piece of code that can prove otherwise, lets all please consider this
to be the case.]

Dave Horsfall (VK2KFU),  Alcatel STC Australia,  dave@stcns3.stc.oz.AU
dave%stcns3.stc.oz.AU@uunet.UU.NET,  ...munnari!stcns3.stc.oz.AU!dave