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From: uucp%ihnp4.UUCP@HARVARD.HARVARD.EDU (UUCP Admin)
Subject: Warning From uucp
Date: Thu, 17-Oct-85 12:54:50 EDT	[thread overview]
Date: Thu Oct 17 12:54:50 1985
Message-ID: <8510171659.AA16125@py.garage.packard.DK> (raw)

We have been unable to contact machine 'delftcc' since you queued your job.

	delftcc!mail sam   (Date 10/14)
The job will be deleted in several days if the problem is not corrected.
If you care to kill the job, execute the following command:

	uustat -kdelftccN14fa
 
	Sincerely,
	ihnp4!uucp

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From seismo!harvard!USC-ECLB.ARPA:INFO-ADA  Mon Oct 14 16:57:50 1985 remote from ihnp4
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From: ihnp4!seismo!ucb-vax.Berkeley.EDU!harvard!uwvax!pokey!dan
Date: 7 Oct 85 15:05:08 GMT
Organization: U of Wisconsin CS Dept
Subject: bug-free programs
Message-Id: <260@pokey.UUCP>
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To: UCB-VAX.Berkeley.EDU!info-ada
Resent-Date: Sun 13 Oct 85 15:47:28-PDT
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Resent-Message-Id: <12150885483.35.INFO-ADA@USC-ECLB.ARPA>

   For anyone who is used to reading the horror stories in Software
Engineering News, the idea of bug-free large programs is a bit hard to
grapple with.  Large programs are so complex, and have so many states,
that exhaustive testing would take hundreds or thousands of years.
Even in the unlikely event that you do have a mechanical proof system,
that system is vulnerable to the input and output predicates for a given
code fragment.
   The important thing about Ada exceptions is that they include the
ability to trap constraint and range violations like the one which
would supposedly appear on the pilot's display.  Proper coding standards
will enforce the creation of programs in which these (unlikely but
possible) errors would be trapped and dealt with in an orderly way.
   Sure beats the heck out a C program that goes off the end of an array
and fires your ejection seat . . .
   -- Dan

             reply	other threads:[~1985-10-17 16:54 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
1985-10-17 16:54 UUCP Admin [this message]
  -- strict thread matches above, loose matches on Subject: below --
1985-10-17 16:56 Warning From uucp UUCP Admin
1985-10-17 16:55 UUCP Admin
1985-10-17 16:54 UUCP Admin
1985-10-17 16:53 UUCP Admin
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