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Re: strlen on a NULL


I can remember crashing HPUX ten years ago due to this `anomoly`.  True
different systems reacted differently.

Lou Zirko

On 09:25 AM 5/12/98 PDT entities calling themselves Rich Hyde spewed the
following words of wisdom:
>On some of the original UNIX machines address 0 was mapped and pointed to
the 
>magic number at the start of the kernel object. 
>
>It was common on these systems to find files in the filesystem with this 
>string as a name.  This was true for most PDP11s.  On the VAX the
location 
>often contained a zero.  On the early SUN and some other platforms 
>address zero was typically not a valid address, and they would core dump.
 
>Some of these platforms had hardware limitations that made mapping zero 
>either hard or impossible.  So they maintained it was a software bug.
Others
>were offended by the sloppiness and deliberately did not fix this.
>
>It became a big enough problem that many UNIXes provided a 
>kernel compilation flag to not map address zero if you wanted to make
sure 
>that the code you developed would work on other systems.
>
>It started out as a bug, then some depended on it as a feature, then it
became 
>a bug again.  I stopped tracking this bug 12 or more years ago so I do
not 
>know if the mindless masses have decided that it is a bug or a feature
again, 
>as these things seem to change with the wind.
>
>Rich
>
>-
>For help on using this list (especially unsubscribing), send a message to
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>
>
Lou Zirko

Key fingerprint = E89C 8AA2 52C7 0E7B 73D1  1D96 2EF3 7B3D 864D FADE
"Were all bozos on this bus", Nick Danger, Third Eye

-----BEGIN GEEK CODE BLOCK-----
Version: 3.1
GCM d+(--)@>- s+(++)>+++:+(++)> a+ C++(++++)$
UBLUAVHIOSC*++++(on++++)$>++++ P++(+++)$ L++++$ E$ W++(+++)$ N++(+++)>$ o>$
!K(---) w+++(++++)$ O$ !M V-$ PS+(+++)@ PE@ Y++>$ PGP++(+++)$ t+>$ !5 X++>$
R+>$ tv+>$ b++ DI++(++++)>+++$ D++>$ G++>$ e++(+++)? h+(++)>$ r>$ y 
------END GEEK CODE BLOCK------ 
-
For help on using this list (especially unsubscribing), send a message to
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