SCOUG-Programming Mailing List Archives

<< Previous Message << >> Next Message >>

Date:	Thu, 17 Sep 1998 17:07:14 PDT
From:	MDINET!ELMONTE!TomE@mdipo.attmail.com (Emerson, Tom # GPS-MDI)
Reply-To:	scoug-programming@scoug.com
To:	pskye@peterskye.com (Peter Skye), scoug-programming@scoug.com (internet!scoug.com!scoug-programming)
Subject:	SCOUG-Programming: Fixpak 8 fixes

Content Type: text/plain

On Thursday, September 03, 1998 4:58 PM, Peter Skye
[SMTP:attmail!internet!peterskye.com!pskye] wrote:
> Hi.
>
> Fixpak 8 now out. APAR list contains following entry:
>
> APAR= JR12286
> PANIC IN VDMMKILLVDM.
>
> Anybody know what "panic" means when referring to a software routine?
>
> - Peter Skye

Generally, an error condition the programmer didn't want to take the time
to "gracefully" recover from ;)

For example, you, "John Q. Programmer" have been assigned the task of
writing a division routine. You write something "on the back of a
napkin", [such as subtract the divisor from the dividend and count how
many times you do this until the dividend reaches zero] and implement it
-- it works fine for all of YOUR test cases, so you put it into
production. Runs fine for a week, then, mysteriously, your code returns
an OVERFLOW condition to the calling routine [can you see why?] The
calling routine doesn't know what to do with an OVERFLOW condition,
because that is not one of the "allowable" conditions that your routine
can return, so it "panics".

In Linux systems, there is the concept of a "kernel panic", which is to
say a serious error introduced (or detected) at the "kernel" level. One
example of this is a disk failure when reading the image of the kernel
itself. [side note: Linux "boots" by loading essentially everthing
needed for the core functions as a single file from the disk -- this file
is called the Kernel and is directly equivelent to ms/pcdos.sys, for
instance]

=====================================================

To unsubscribe from this list, send an email message
to "steward@scoug.com". In the body of the message,
put the command "unsubscribe scoug-programming".

For problems, contact the list owner at
"rollin@scoug.com".

=====================================================

Return to [ 17 | September | 1998 ]

SCOUG, Warp Expo West, and Warpfest are trademarks of the Southern California OS/2 User Group. OS/2, Workplace Shell, and IBM are registered trademarks of International Business Machines Corporation. All other trademarks remain the property of their respective owners.