quoted
int a[100], b = 123;
a[b] = 0;
I guess I'm taking exception to your use of the phrase "all
software".
quoted
What I mean is, if &a = 0x10000, then a[b] will always write
0 to 0x101ec.
That may not be smart, may not be what you intended to do,
but the uP will
always do the exact same thing. (Does this mean 'C' is
unreliable because
it lets you do things like that?)
Yes, 'C' is unreliable because writing beyond the
"maxindex" lets you overwrite other's data, other's
code and DOES make backdoor for viruses.
On the other hand testing every index every time
for min and max slowes the executing.
So what?
Ludwig
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Mészáros Lajos wrote:
Yes, 'C' is unreliable because writing beyond the "maxindex" lets
you overwrite other's data, other's code and DOES make backdoor for
viruses.
On the other hand testing every index every time for min and max slowes
the executing.
QNX does not, and Linux does not, and with both C is as unreliable as ever.
However, a failure in a QNX in the driver level is not as potentially
malicious as in Linux. While this does not exclude failure, and does not
say a thing about the actual quality of QNX or Linux code, it's a nice
_additional_ feature related towards stability.
I guess Linux lacking proper certification for some applications is a
much bigger obstacle in the minds of managers, anyway.
But somehow this is getting offtopic, quickly, isn't it?
With kind regards,
Oliver Korpilla
** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/
Oliver Korpilla wrote:
Mészáros Lajos wrote:
quoted
Yes, 'C' is unreliable because writing beyond the "maxindex" lets
you overwrite other's data, other's code and DOES make backdoor for
viruses.
On the other hand testing every index every time for min and max slowes
the executing.
QNX does not, and Linux does not, and with both C is as unreliable as ever.
However, a failure in a QNX in the driver level is not as potentially
malicious as in Linux. While this does not exclude failure, and does not
say a thing about the actual quality of QNX or Linux code, it's a nice
_additional_ feature related towards stability.
I guess Linux lacking proper certification for some applications is a
much bigger obstacle in the minds of managers, anyway.
But somehow this is getting offtopic, quickly, isn't it?
With kind regards,
Oliver Korpilla
If C is not reliable enough then nothing is. In assembly(or even
handcoded machine language for the real hard core people) you can do
just about anything. Since all languages must resort to this at some
point, our foundation is built on sand and we are eternaly screwed.
Only the 4 last words of the last sentence of this statement is false.
Its not the languages job to write good solid code or verify it, its the
programmers responsibility. The only code you can truly trust is code
you have total control over. For truly solid code, no funky error
checking computer science language will ever replace good practices,
thorough testing, and documentation.
The reason for this is obvious, at some point higher level languages
must be built using a lower language to avoid the chicken/egg paradox.
Hence the quality of a higher level language can never be assured since
its foundation is made of sand.
Its a poor musician that blames their instrument.
-- Conn Clark
*****************************************************************
Give a man a match and you heat him for a moment. Set him on fire
and you'll heat him for life.
*****************************************************************
Conn Clark
Engineering Stooge clark@esteem.com
Electronic Systems Technology Inc. www.esteem.com
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