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Re: Commit strip OTD: Talk to me!

Rage3-Jul-20 22:42

Rage

3-Jul-20 22:42

That's the Schroedinger error.

Do not escape reality : improve reality !

Re: Commit strip OTD: Talk to me!

Greg Utas4-Jul-20 0:13

Greg Utas

4-Jul-20 0:13

Or a log flood that consumes all available resources. Big Grin | :-D

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Re: Commit strip OTD: Talk to me!

Daniel Pfeffer4-Jul-20 8:04

Daniel Pfeffer

4-Jul-20 8:04

The dread heisenbug strikes again!

Freedom is the freedom to say that two plus two make four. If that is granted, all else follows.
-- 6079 Smith W.

Re: Commit strip OTD: Talk to me!

jsc424-Jul-20 10:32

jsc42

4-Jul-20 10:32

Daniel Pfeffer wrote:
The dread heisenbug strikes again!

are you sure? I have some uncertainty (in principle)

Re: Commit strip OTD: Talk to me!

dandy725-Jul-20 3:25

dandy72

5-Jul-20 3:25

This is like problems that only happens in release mode - but work perfectly fine in debug mode.

But then, there's entire articles dedicated to this topic...

Re: Commit strip OTD: Talk to me!

honey the codewitch5-Jul-20 3:29

honey the codewitch

5-Jul-20 3:29

dandy72 wrote:
But then, there's entire articles dedicated to this topic...

Which can be boiled down to "your 'uninitialized' variables are getting initialized to different values in debug than release"

Laugh | :laugh:

Real programmers use butterflies

Re: Commit strip OTD: Talk to me!

dandy726-Jul-20 2:31

dandy72

6-Jul-20 2:31

Nowadays, sure.

I wasn't clear with my intent, but I meant there's numerous articles discussing how to debug release-mode apps, not why apps might behave differently.

Any interest in something like the following?

honey the codewitch3-Jul-20 17:31

honey the codewitch

3-Jul-20 17:31

I have the basis for what might be an interesting article in and of itself within my MIDI library.

There's a very tricky call i have to make that relies on passing essentially variable length structs, and consequently, the .NET marshaller cannot handle it out of the box. Instead of using StructLayoutAttribute and MarshalAsAttribute to mark up your structure and p/invoke function calls, you basically need to use StructLayoutAttribute and then use the Marshal class methods to copy the variable length portion in manually.

I don't know how many people have run into P/Invoking into C style libraries that take variable length structs, so is anyone interested in this?

I'd rather put this out there up front before I spend time and effort on an article that nobody cares about, and this is kind of arcana.

Edit: Big thanks folks. Your responses let me know there was some interest and I'm in the process of writing it.

Real programmers use butterflies

modified 4-Jul-20 7:37am.

Re: Any interest in something like the following?

Garth J Lancaster3-Jul-20 19:28

Garth J Lancaster

3-Jul-20 19:28

As you and I have discussed, I think it would be worthwhile .. sure, I can pull apart your code and but that won't necessarily make it obvious

This will become another resource, along with Luc Pattyn's Article: P/Invoke, part 1 and to a much lesser extent pinvoke.net: the interop wiki!

My biggest achievement along the same lines I can't show in code, a) because it was commercial - wrapping a c++ PGP library and creating a C# layer for it, b) iirc it was relatively 'simple' structs etc

Re: Any interest in something like the following?

honey the codewitch4-Jul-20 6:40

honey the codewitch

4-Jul-20 6:40

Here you go: P/Invoke Jujitsu: Passing Variable Length Structs[^]

Real programmers use butterflies

Re: Any interest in something like the following?

Luc Pattyn5-Jul-20 12:47

Luc Pattyn

5-Jul-20 12:47

Luc Pattyn [My Articles] Nil Volentibus Arduum

Re: Any interest in something like the following?

Jon McKee3-Jul-20 20:52

Jon McKee

3-Jul-20 20:52

I'd read it Thumbs Up | :thumbsup:

Re: Any interest in something like the following?

honey the codewitch4-Jul-20 10:37

honey the codewitch

4-Jul-20 10:37

I posted it here: P/Invoke Jujitsu: Passing Variable Length Structs[^]

I hope you enjoy it.

I've been doing p/invoke so long and C coding before that that I kind of forget what people don't know when it comes to it. I didn't want to recover beginner P/Invoke stuff but let me know if I didn't explain something very well, when you get a chance to look at it.

Real programmers use butterflies

Re: Any interest in something like the following?

Jon McKee4-Jul-20 14:28

Jon McKee

4-Jul-20 14:28

honey the codewitch wrote:
I was just teasing earlier, I'd have never made you type that much. What kind of monster do you take me for?

I was thinking about MarshalAs while reading about the MIDIHDR structure definition. Actually lol'd when I got to this part Laugh | :laugh:

I thought the article was really interesting. I've done p/invoke and marshalling stuff before but I learned quite a bit here. I had no idea about the StringBuilder trick for example Thumbs Up | :thumbsup:

I really enjoyed it!

Re: Any interest in something like the following?

honey the codewitch4-Jul-20 14:44

honey the codewitch

4-Jul-20 14:44

That's good to hear. I'm glad you enjoyed it.

And thank you!

Real programmers use butterflies

modified 4-Jul-20 21:13pm.

Re: Any interest in something like the following?

pkfox3-Jul-20 22:07

pkfox

3-Jul-20 22:07

I'd certainly read it

"We can't stop here - this is bat country" - Hunter S Thompson - RIP

Re: Any interest in something like the following?

honey the codewitch4-Jul-20 10:38

honey the codewitch

4-Jul-20 10:38

P/Invoke Jujitsu: Passing Variable Length Structs[^]

Here you go. If I didn't explain something regarding how to do this technique very well, let me know and I'll append the article. I've been doing P/Invoke so long I may take for granted things people don't know.

Real programmers use butterflies

Re: Any interest in something like the following?

pkfox5-Jul-20 0:16

pkfox

5-Jul-20 0:16

Just read it - very cool stuff going on in there - I love this kind of lowish level tech - well done

"We can't stop here - this is bat country" - Hunter S Thompson - RIP

Re: Any interest in something like the following?

honey the codewitch5-Jul-20 2:02

honey the codewitch

5-Jul-20 2:02

pkfox wrote:
I love this kind of lowish level tech

back in my day (1986 or so) that was called programming. Laugh | :laugh:

Seriously though, I'm always glad to know when someone appreciates one of my articles. thanks

Real programmers use butterflies

Re: Any interest in something like the following?

Nelek4-Jul-20 7:36

Nelek

4-Jul-20 7:36

I have read it, but another thing is to understand everything D'Oh! | :doh:

M.D.V.

If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
Help me to understand what I'm saying, and I'll explain it better to you
Rating helpful answers is nice, but saying thanks can be even nicer.

Re: Any interest in something like the following?

honey the codewitch4-Jul-20 7:41

honey the codewitch

4-Jul-20 7:41

I welcome questions. I really wish it was something i could demonstrate with puppets. Big Grin | :-D

Real programmers use butterflies

Re: Any interest in something like the following?

Nelek4-Jul-20 11:32

Nelek

4-Jul-20 11:32

honey the codewitch wrote:
I welcome questions

Good to know

M.D.V.

Re: Any interest in something like the following?

honey the codewitch4-Jul-20 11:39

honey the codewitch

4-Jul-20 11:39

I have a background in bit twiddling on 8 bit and 16 bit machines in asm and later C so when I see a struct I automatically visualize its layout in memory. It makes doing p/invoke easy but hard to explain because i take things for granted that other people maybe struggle with.

I think it hurts my writing. So I'm serious, when you get a chance, if the way I'm writing and presenting this material makes it difficult for you or other readers to understand it, you are the most helpful resource around to me and I'd love your help in helping me explain it better, if that makes sense.

And if you're not interested or you don't have time that's okay too. Smile | :)

Real programmers use butterflies

modified 4-Jul-20 18:24pm.

Re: Any interest in something like the following?

Nelek4-Jul-20 13:47

Nelek

4-Jul-20 13:47

Have you seen the second sentence of my signature?

I know what you mean.

I'll re-read it and give you a feedback, but it might get some time.

M.D.V.

Re: Any interest in something like the following?

honey the codewitch4-Jul-20 13:53

honey the codewitch

4-Jul-20 13:53

okay, fair enough. Smile | :)

Real programmers use butterflies

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