It's part of a test and I'm stumped. There is a function
void foo(char **x)
The function signature is given and cannot be changed, so no passing
of other values. The test case involves defining this variable:
char *y[] = { /* bunch of stuff */ }
and calling
foo(y)
In the above, "bunch of stuff" is a series of triplets, two strings
followed by a null string (""). However, the last triplet ends with an
integer 0. This seems that it's supposed to signify the end of the
array. However, it appears to me that 0 is the same binary value as
for the empty string (NUL, \0, whatever). So in effect, one cannot
test for it as a sentry value because it's actually the same as the
preceding triplets.
How then, can the function foo() determine the bounds of the array?
Knowing the bounds of the particular test case is not sufficient since
the actual test suite may have arrays of varying size.
Oct 8 '08
30  3618 
CBFalconer <cb********@yah oo.comwrites:
Richard Bos wrote:
>la************@ siemens.com wrote:
... snip ...
>>
>>Even programmers *with* database experience. Oracle, for
example, continues to treat empty string values and nulls
identically , although they have warned (forever) that that
could change some time in the future.
Now, I'm not much of an SQL expert, certainly not compared to
the people at Oracle, but... isn't that illegal?
No, it isn't. First, they can certainly design their own functions
in any fashion they wish. Second, even if implementing C standard
functions, this is simply imposing a definition for 'undefined
behavior' on THEIR system.
I think Richard's question was about SQL, not about C.
In the interest of redirecting the question to a more appropriate
place, <http://en.wikipedia.or g/wiki/Sql_nullseems to provide an
answer; see 9.1, "Common mistakes".
--
Keith Thompson (The_Other_Keit h) ks***@mib.org <http://www.ghoti.net/~kst>
Nokia
"We must do something. This is something. Therefore, we must do this."
-- Antony Jay and Jonathan Lynn, "Yes Minister" This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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