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It would mean that the function may throw only exceptions of class "type". Look up "exception specification" in some proper C++ reference. Exception specifications aren't supported by VC++6.
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markkuk wrote:
Exception specifications aren't supported by VC++6.
You sure about that? The first hit in MSDN when searching for "exception specification" shows examples of VC code using exception specifications.
--Mike--
My really out-of-date homepage
Buffy's on. Gotta go, bye!
Sonork - 100.10414 AcidHelm
Big fan of Alyson Hannigan.
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Michael may be this gauy is confused for the following:
Microsoft Specific —>
Microsoft C++ does not support the function exception specification mechanism, as described in section 15.4 of the ANSI C++ draft.
I found that in the MSDN under Exception Handling Syntax It's a little confuss butc don't said that VC doesn't support Exception specifications...
Reagards...
![Green Alien | [Alien]](https://codeproject.freetls.fastly.net/script/Forums/Images/alien.gif) Today is Friday!!! ![Beer | [beer]](https://codeproject.freetls.fastly.net/script/Forums/Images/beer.gif) and Party!!!
Carlos Antollini.
Sonork ID 100.10529 cantollini
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If you declare something like:
void SampleFunction(void) throw (int)
{
}
and compile, you will get
warning C4290: C++ Exception Specification ignored
I vote pro drink
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I am not sure a raw beginner should be directly jumping into COM. Anyway good luck!
Nish
Sonork ID 100.9786 voidmain
www.busterboy.org
If you don't find me on CP, I'll be at Bob's HungOut
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I have huge files (<100Mb ) and want to map a number of the to mem. First up How do I determine where to start to map in memory? I am using NT so how do I know how much it is using.
And if you can help , how would you go about mapping large files in the first place?
Thanks
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The functions will tell you exactly where the mapping starts.
Use CreateFileMapping() to create a mapping to file and MapViewOfFile() to load a portion (or all file) into memory. The last function will return you LPBYTE, points to the start of mapping 
Look for descriptions of the functions in MSDN.
Philip Patrick
"Two beer or not two beer?" <shakesbeer>
Web-site: www.saintopatrick.com
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Anyone know of a good class to enumerate all of the files in a directory with a given extension?
Ex: all files in c:\temp with extension .xyz
Marcus Spitzmiller
"Ha ha, Stupid bloropope.." - Homer
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CFileFind.
/ravi
"There is always one more bug..."
http://www.ravib.com
ravib@ravib.com
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Thanks, too! You just beat my post.
Marcus Spitzmiller
"Ha ha, Stupid bloropope.." - Homer
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CPians are really fast at answering questions 
Nish
Sonork ID 100.9786 voidmain
www.busterboy.org
If you don't find me on CP, I'll be at Bob's HungOut
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Looks like I should've looked around a bit longer:
CFileFind
Marcus Spitzmiller
"Ha ha, Stupid bloropope.." - Homer
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Hi all,
I would like to know if VC++ 7.0, that's what I heard is the next version, if it is a seperate commercial release or if it is part of MS .NET studio?
Thanks,
Don Cathcart
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VC++ 7.0 is part of Visual Studio .NET
Sonork ID 100.9786 voidmain
www.busterboy.org
If you don't find me on CP, I'll be at Bob's HungOut
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Thanks, that was fast?
Is there a Standard, Pro and Enterprise versions of Visual Studio .NET?
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I guess there would be at least two editions, perhaps even more.
Nish
Sonork ID 100.9786 voidmain
www.busterboy.org
If you don't find me on CP, I'll be at Bob's HungOut
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MasterBlaster?
Here that's what we call Sachin Tendulkar .
Nish
Sonork ID 100.9786 voidmain
www.busterboy.org
If you don't find me on CP, I'll be at Bob's HungOut
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Nish [BusterBoy] wrote:
MasterBlaster?
Here that's what we call Sachin Tendulkar .
Really, in England we call him "oh no, not him again. Let's just put 150 runs on the board. It saves time and effort" 
Michael
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I thought STL was a bit more optimized than this. While I would expect and simple array to be faster I was surprised at the amount of difference. Using the two functions below I got the following timing results.
FooList: 0.0013247494 seconds
FooArray: 0.0000005587 seconds
std::list<DWORD> FooList()
{
std::list<DWORD> list;
for(int x = 0; x < 50; x++)
list.push_back(x);
return list;
}
void FooArray(DWORD* list)
{
for(int x = 0; x < 50; x++)
list[x] = x;
}
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It depends - what STL implimentation are you using ? I admit I've never done this sort of testing, but while I'd expect some overhead, I assume you're using the version that comes with VC for results as poor as this.
Christian
I have come to clean zee pooollll. - Michael Martin Dec 30, 2001
Sonork ID 100.10002:MeanManOzI live in Bob's HungOut now
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I am using the VC version, never gave it a thought. What other implementations have you worked with?
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You are talking about arrays, but your sample uses std::list 
Maybe you should change your code to following:
std::list<int> FooList()
{
std::list<int> list;
for(int x = 0; x < 50; x++)
list.push_back(x);
return list;
}
Regards
Thomas
Finally with Sonork id: 100.10453 Thömmi
Disclaimer:
Because of heavy processing requirements, we are currently using some of your unused brain capacity for backup processing. Please ignore any hallucinations, voices or unusual dreams you may experience. Please avoid concentration-intensive tasks until further notice. Thank you.
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There is no way in hell a container class could ever be as optimized as an unbounded, well defined array fill.
Here are some of the differences between your FooArray and FooList.
1. As someone else pointed out, you are using a list and not a vector. A vector would be a more valid test.
2. std::vector does bounds checking and reallocates the data buffer using a doubling algorithm. Your FooArray routine does no bounds checking and is limited to only 50 elements.
3. Passing the list (or vector) is just a bit slower. You can double the performance by passing in a destination list into the routine via a reference.
4. Only runing the routine once is not a valid test. In my tests in release mode, executing each routine 10000 times yielded this information:
list - 6770 ms
vector - 841 ms
array - 30 ms
With the optimization of passing the list and vector into the routine:
list - 3175 ms
vector - 811 ms
array - 30 ms
If you don't destruct the list or vector each loop iteration and just invoke .clear on them, the numbers are as follows:
list - 3090 ms
vector - 290 ms
array - 30 ms
The final optimization I can think of is pre allocating the vector to size 50. However, that change made no difference. The reason being that the clear routine just sets the size back to zero and doesn't deallocate the vector data. Thus, since after the first pass the vector is already sized to 50, invoking reserve to preallocate the vector to 50 does nothing. Which shows the cost of all the memory allocation in vector. 800+ ms to 300 by removing all the allocations. Thus, vector has 270 ms of bookkeeping overhead that FooArray doesn't have.
5. Most optimizers can not handle deeply nested inlining well. It is very easy to optimize the hell out of FooArray. However, the compiler has much more trouble optimizing FooList since the implementation is deeply nested and more complex.
Tim Smith
Descartes Systems Sciences, Inc.
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Great comments.
I wanted to point out on #2 that bounds checking with vector only happens if you use .at(). For the regular [] index method, there is no bounds checking with vector.
CodeGuy
The WTL newsgroup: over 1100 members! Be a part of it. http://groups.yahoo.com/group/wtl
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Ah, you are right. I didn't know that.
Tim Smith
Descartes Systems Sciences, Inc.
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