Path: utzoo!attcan!uunet!samsung!sdd.hp.com!hp-pcd!hplsla!tomb
From: tomb@hplsla.HP.COM (Tom Bruhns)
Newsgroups: comp.sys.amiga
Subject: Re: Write protect mechanisms (was Re: Virus)
Message-ID: <5160093@hplsla.HP.COM>
Date: 12 Apr 90 15:56:46 GMT
References: <9004102044.AA12596@jade.berkeley.edu>
Organization: HP Lake Stevens, WA
Lines: 20

JTREWORGY@Wesleyan.BITNET (James Treworgy) writes:
>> In article <9004061744.AA13588@jade.berkeley.edu> C503719@UMCVMB.MISSOURI.EDU
>>   ("Baird McIntosh") writes:
>>   [stuff deleted]
>>>hope that my assessment is incorrect.  In any case, I don't think there is a
>>>way in software to write to a write-protected disk; the hardware won't allow
>>>this type of write to occur (which is perfectly reasonable and expected).
>>>
>> Unfortunately, the write protect mechanism involves an optical detector. If th
>   e
>> light source is not functioning it is the same as write-enabling the disk. A

Actually, many, if not most or all, 3.5" drives use a microswitch to detect
the write0-protect tab.  This modifies your arguement slightly, since the
switch could stick in either position.  Of course, the electronics in an
optical sensor could fail in either mode, too; LEDs don't "burn out" like
incandescant lamps, so that's not _necessarily_ the predominant failure
mechanism.

(stuff deleted)