I thought .NET was supposed to make things easier, if anything, than unmanaged code.
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You would have to cross-compile if you go the route of compiling a separate library (in, let's say, C) for this stuff. But you can also go with P/Invoke which you "cross compile" via runtime checks. .NET Core supports this scenario, I haven't checked on Mono (yet). https://stackoverflow.com/questions/38790802/determine-operating-system-in-net-core
yeah in the general sense, but in this case, i'd need two binaries per platform (one managed, one unmanaged) probably. #ifs require compilation of course, in C# as well as C
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.
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yeah in the general sense, but in this case, i'd need two binaries per platform (one managed, one unmanaged) probably. #ifs require compilation of course, in C# as well as C
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.
Why do you insist on an unmanaged binary? Why don't you want to do your unmanaged ABI calls with P/Invoke?
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Why do you insist on an unmanaged binary? Why don't you want to do your unmanaged ABI calls with P/Invoke?
Because it's impossible to map a file to process address space in C#. You can only marshal calls to the vmem system which makes it exactly like reading and writing a file instead of reading and writing a pointer. Defeating the primary reason I'd use it. what I want (and can't have)
var foo = new int[100000]; // backed by disk automatically
and i don't want an unmanaged binary. I'm speaking in the hypothetical. I will not use vmem in this project because of .NET limitations.
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.
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Because it's impossible to map a file to process address space in C#. You can only marshal calls to the vmem system which makes it exactly like reading and writing a file instead of reading and writing a pointer. Defeating the primary reason I'd use it. what I want (and can't have)
var foo = new int[100000]; // backed by disk automatically
and i don't want an unmanaged binary. I'm speaking in the hypothetical. I will not use vmem in this project because of .NET limitations.
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.
Write an "array" class which looks like an array from the outside but works with ABI calls internally. Using container classes is often recommended over using plain arrays in C# anyway.
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I'm aware of that. I worked on the Visual Studio team at microsoft. I know a little about .NET
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.
I'm not sure why you feel the need to tell me that you worked at Microsoft. If you were trying to imply that it adds credibility to what you say, I've go to tell you that I've met some real nimrods who came from Microsoft to those MVP summits I used to go to. I'm sure that a number of exceptionally talented people work or have worked at Microsoft, but there are also these nimrods (who thought they were exceptionally talented). A random sample could belong to either camp. Because you had to say that, I had to say this.
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Yes, though it was added to .NET after my initial attempt at using mem mapped files from C#. Besides all that is is a wrapper like the one i had written years ago. It doesn't change the basic problem which is: var foo = new int[1000000]; //backed by disk, paged automatically, in C/C++ it's mainly because you can't use pointers in C#, and even if you use unsafe, you cannot pin objects to specific addresses in memory
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.
So you can't pin?: whatabout [fixed Statement - C# Reference | Microsoft Docs](https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/fixed-statement) So I think it's time to use the latest .NET Version and have a look into what has changed...
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So you can't pin?: whatabout [fixed Statement - C# Reference | Microsoft Docs](https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/fixed-statement) So I think it's time to use the latest .NET Version and have a look into what has changed...
pinning does not solve this problem. I don't need a random pointer .NET produced from the GC heap. The only thing i could do with that is throw it away. It's useless for this
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.
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I'm not sure why you feel the need to tell me that you worked at Microsoft. If you were trying to imply that it adds credibility to what you say, I've go to tell you that I've met some real nimrods who came from Microsoft to those MVP summits I used to go to. I'm sure that a number of exceptionally talented people work or have worked at Microsoft, but there are also these nimrods (who thought they were exceptionally talented). A random sample could belong to either camp. Because you had to say that, I had to say this.
No I'm telling you i don't need your lectures about the very basics of how .NET works. I don't care if you find me credible because your opinion doesn't matter to me. If that were to change, we'll talk.
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.
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Write an "array" class which looks like an array from the outside but works with ABI calls internally. Using container classes is often recommended over using plain arrays in C# anyway.
it has been done. It's called List/IList and it doesn't help me. It does zero to reduce the complexity of what I'm trying to do. I don't actually need an int array. I need a B+tree. Try wrapping that in something fun and you'll have done my job. :)
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.
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it has been done. It's called List/IList and it doesn't help me. It does zero to reduce the complexity of what I'm trying to do. I don't actually need an int array. I need a B+tree. Try wrapping that in something fun and you'll have done my job. :)
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.
http://csharptest.net/projects/bplustree From the description "BPlusTree is a implementation of the generic IDictionary interface backed by a disk-based B+Tree".
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http://csharptest.net/projects/bplustree From the description "BPlusTree is a implementation of the generic IDictionary interface backed by a disk-based B+Tree".
yeah i've seen that. it's cool. thread safe too as i recall. I'd rather build one. Using that won't teach me anything
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.
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yeah i've seen that. it's cool. thread safe too as i recall. I'd rather build one. Using that won't teach me anything
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.
Then go ahead. Build an own class which runs on platform ABI calls internally guarded by runtime platform checks and implements the interface you want. It's a PITA, that I absolutely agree with but on the other hand, the greater the learning effect and if there's a clean interface, the implementation doesn't matter anyway (except for said learning effect).
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Then go ahead. Build an own class which runs on platform ABI calls internally guarded by runtime platform checks and implements the interface you want. It's a PITA, that I absolutely agree with but on the other hand, the greater the learning effect and if there's a clean interface, the implementation doesn't matter anyway (except for said learning effect).
I'm probably going to write it all in managed code.
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.
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No I'm telling you i don't need your lectures about the very basics of how .NET works. I don't care if you find me credible because your opinion doesn't matter to me. If that were to change, we'll talk.
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.
honey the codewitch wrote:
No I'm telling you i don't need your lectures about the very basics of how .NET works.
I responded to you with a couple of one liners, and you term those as "lectures"?
honey the codewitch wrote:
I don't care if you find me credible
That's probably why you tried desperately to establish that you're sooo good with announcing your "Microsoft backgroundz"? Geez, try and make some sense occasionally.
honey the codewitch wrote:
your opinion doesn't matter to me.
Ha, we finally have something in common.
honey the codewitch wrote:
If that were to change, we'll talk.
No, thank you. X| :thumbsdown:
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I'm probably going to write it all in managed code.
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.
Exactly my point, keep it managed, save yourself the trouble of cross-compiling and furthermore, the distributional pain. Distributing different binaries for different platforms has been the norm for pretty much forever (in computing at least), but .NET Core/Mono provide means to do it better. Hey, remember when even DOS software had to have different binaries for different computer vendors despite them all running DOS? I surely don't miss those days.
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honey the codewitch wrote:
No I'm telling you i don't need your lectures about the very basics of how .NET works.
I responded to you with a couple of one liners, and you term those as "lectures"?
honey the codewitch wrote:
I don't care if you find me credible
That's probably why you tried desperately to establish that you're sooo good with announcing your "Microsoft backgroundz"? Geez, try and make some sense occasionally.
honey the codewitch wrote:
your opinion doesn't matter to me.
Ha, we finally have something in common.
honey the codewitch wrote:
If that were to change, we'll talk.
No, thank you. X| :thumbsdown:
Rajesh R Subramanian wrote:
No, thank you.
Nobody made you respond to me. Now I'm not listening to this anymore. Have good day.
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.
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Rajesh R Subramanian wrote:
No, thank you.
Nobody made you respond to me. Now I'm not listening to this anymore. Have good day.
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.
honey the codewitch wrote:
Nobody made you respond to me.
If you're a nobody, then yes.
honey the codewitch wrote:
Now I'm blocking you so I don't have to listen to this anymore.
TMI - I don't need to know what you are doing on the internet.
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Exactly my point, keep it managed, save yourself the trouble of cross-compiling and furthermore, the distributional pain. Distributing different binaries for different platforms has been the norm for pretty much forever (in computing at least), but .NET Core/Mono provide means to do it better. Hey, remember when even DOS software had to have different binaries for different computer vendors despite them all running DOS? I surely don't miss those days.
I planned to keep it managed from the beginning. The only reason i discussed an unmanaged scenario is because memory mapped files basically don't work - at least how they were designed to be used - under .NET. I wanted people to understand the problem domain. I do not make mixed mode distributions anymore.
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.
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I know this is a very special case but still i ran headlong into it. The easiest way to implement a B+ tree on disk is using a memory mapped file. I think this is what SQL Server does, but don't quote me. However, the only way you can access memory mapped files in C# is through .NET interop which makes it useless. Because one of the points of a memory mapped file is that you can do memory allocations that are backed by disk. There's no way in hell .NET can give you that in its current incarnation, even if one were to write a custom host, because of the way a GC system works. What I'd like var foo = new int[1000000]; // backed by disk, paged automatically What I'd have to do. somepointer = VirtualAlloc(...) Write(somepointer, data) etc etc basically it works like file i/o which defeats essentially the whole purpose. =(
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.
[This StackOverflow question](https://stackoverflow.com/questions/31179076/how-to-get-an-intptr-to-access-the-view-of-a-memorymappedfile) appears to allow you to get a fixed pointer to a mapped view. Then you could use a `Span` object to provide an array representation over that memory range (use the [constructor that takes a `Void*` and `Int32`](https://docs.microsoft.com/en-us/dotnet/api/system.span-1.-ctor?view=netstandard-2.1#System\_Span\_1\_\_ctor\_System\_Void\_\_System\_Int32\_)) and then writes to the `Span` would be written to the mapped memory and thus to the mapped file?
Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p
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[This StackOverflow question](https://stackoverflow.com/questions/31179076/how-to-get-an-intptr-to-access-the-view-of-a-memorymappedfile) appears to allow you to get a fixed pointer to a mapped view. Then you could use a `Span` object to provide an array representation over that memory range (use the [constructor that takes a `Void*` and `Int32`](https://docs.microsoft.com/en-us/dotnet/api/system.span-1.-ctor?view=netstandard-2.1#System\_Span\_1\_\_ctor\_System\_Void\_\_System\_Int32\_)) and then writes to the `Span` would be written to the mapped memory and thus to the mapped file?
Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p
Oooh now that's clever.I forgot about span! Hmmm. this might be doable. thanks for the link. Span is cool.
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.