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A customer asked me to create a powerpoint explaining the advantages of LabVIEW. While putting together the practical rationales, just for grins I asked Chatgpt to create a presentation explaining the philosophy of LabVIEW in a Zen sort of way. Here is what it came up with. Zen_of_LabVIEW.pdf

I spent a long time online with YouTube support and finally got to the bottom of it. The Channel is back, and all the links work!

Phew that is a pretty strong opinion! Although I personally am not a fan of the overall style of DQMH none of my problems are with the scripting/wizards or placeholder text. I think any framework that tries to do "a lot" will be complicated... your own personal framework (which you likely find trivial to use) is likely to be a bit weird to others. DQMH is extremely popular for a reason... To paraphrase the words of a wiser person than I, "please don't yuck someone elses yum"

Many years ago I made a demo for myself on how to drag and drop clones of a graph. I wanted to show a transparent picture of the new graph window as soon as the drag started, to give the user immediate feedback of what the drag does and the window to be placed exactly where it is wanted. I think I found inspiration for that on ni.com or here back then, but now I cannot find my old demo, nor the examples that inspired me back then. Now I have an application where I want to spawn trends of a tag if you drag the tag out of listbox and I had to remake the code...(see video below). At first I tried to use mouse events to position the window, but I was unable to get a smooth movement that way. I searched the web for similar solutions and found one that used the Input device API to read mouse positions to move a window without a title and that seemed to be much smoother. The first demo I made for myself is attached here (run the demo and drag from the list...). It lacks a way to cancel the drag though; Once you start the drag you have a clone no matter what. dragtrends.mp4 Has anyone else made a similar feature? Perhaps where cancelling is handled too, and/or with a more generic design / framework? Drag window out of listbox - Saved in LV2018.zip

The examples you provide are invalid JSON, which makes it difficult to understand what you are actually trying to do. In your VI, the input data is a 2D array of string but the JSON output is completely different. Your first step should be to define the types you need to produce the expected JSON output. Afterwards you can map your input data to the output data and simply convert it to JSON. The structure of the inner-most object in your JSON appears to be the following: { "Type":"ABC", "IP":"192.168.0.0", "Port":111, "Still":1, "Register":"Register", "Address":12345, "SizeLength":1, "FET":2, "Size":"big", "Conversion":"small" } In LabVIEW, this can be represented by a cluster: When you convert this cluster to JSON, you'll get the output above. Now, the next level of your structure is a bit strange but can be solved in a similar manner. I assume that "1", "2", and "3" are instances of the object above: { "1": {}, "2": {}, "3": {} } So essentially, this is a cluster containing clusters: The approach for the next level is practically the same: { "TCP": {} } And finally, there can be multiple instances of that, which, again, works the same: { "EQ1": {}, "EQ2": {} } This is the final form as far as I can tell. Now you can use either JSONtext or LabVIEW's built-in Flatten To JSON function to convert it to JSON {"EQ1":{"TCP":{"1":{"Type":"ABC","IP":"192.168.0.0","Port":111,"Still":1,"Register":"Register","Address":12345,"SizeLength":1,"FET":2,"Size":"big","Conversion":"small"},"2":{"Type":"ABC","IP":"192.168.0.0","Port":111,"Still":1,"Register":"Register","Address":12345,"SizeLength":1,"FET":2,"Size":"big","Conversion":"small"},"3":{"Type":"ABC","IP":"192.168.0.0","Port":111,"Still":1,"Register":"Register","Address":12345,"SizeLength":1,"FET":2,"Size":"big","Conversion":"small"}}},"EQ2":{"TCP":{"1":{"Type":"ABC","IP":"192.168.0.0","Port":111,"Still":1,"Register":"Register","Address":12345,"SizeLength":1,"FET":2,"Size":"big","Conversion":"small"},"2":{"Type":"ABC","IP":"192.168.0.0","Port":111,"Still":1,"Register":"Register","Address":12345,"SizeLength":1,"FET":2,"Size":"big","Conversion":"small"},"3":{"Type":"ABC","IP":"192.168.0.0","Port":111,"Still":1,"Register":"Register","Address":12345,"SizeLength":1,"FET":2,"Size":"big","Conversion":"small"}}}} The mapping of your input data should be straight forward.

In a previous life, I used to teach a CLD level class using this book, and enjoyed it a lot -- Some of it is certainly outdated at this point, but I think it still has a lot of solid info / strategies in it. I've attached the files as a .zip file to this post. Good luck! Effective LabVIEW Programming Files.zip

I have put some effort into improving the VI icons in Messenger Library, in hopes of making things clearer. I have particularly been trying to get rid of the magnifying glass icon, which was standing in for too many concepts. I have also tried to improve the Palettes by putting the standard VIs (that one would most commonly use) in the root-level palette: The 2.0 version also introduces Malleable API methods (the orange-coloured ones), which make code cleaner. If anyone could spare some time, it would help me to have feedback. Especially from people who have not used Messenger Library before, so I can get an idea if the key concepts come across. New 2.1.3 version is available here: https://forums.ni.com/t5/JDP-Science-Tools/New-icons-for-Messenger-Library/m-p/4412550#M192

You want an ability to override the Equality or Comparison operators? I'm unsure, whether it really existed in OpenG packages, but now you have those neat malleable VIs, that let you do that: Search Unsorted 1D Array , Sort 1D Array , Search Sorted 1D Array. They have an additional input to specify your own equals or less function in a form of a custom comparison class or a VI refnum. There's an article to help: Creating a Custom Sorting Function in LabVIEW

This is exactly what was said in that ancient thread: Tree control in labview. So if you add 65536*N to the Item Symbols property of the Listbox and have the "Enable Indentation" option activated, you shift the symbol/glyph and the text N levels to the right. Could be useful for simple 'parent-child' relationships, if you don't want to use a Tree. And still it's used in Find Examples / NI Example Finder window:

I once went for an interview where they gave me a coding test and asked me to modify it. It was a very long time ago so I don't remember the exact modification they wanted (nothing to do with memory leaks) but I do remember the obtain queue and read queue inside a while loop with the release queue outside. I asked if they wanted me to also fix the memory leak as well as the modifications and they were a little puzzled until I explained what you have just said. I must have seen (and fixed) this while-loop bug-pattern a thousand times since then in various code bases. I also created this VI which I generally use instead of the primitives as it intialises on first call, can be called from anywhere, and prevents most foot-shooting by rolling them all into a single VI and ensuring all references but 1 are closed after use. Queue.vi

Those aren't typo's and errors. They are tests to see if we are paying attention.

In the past I have used the IMAQ drivers for getting the image, which on its own does not require any additional runtime license. It is one of those lesser known secrets that acquiring and saving the image is free, but any of the useful tools have a development, and deployment license associated with it. I've also had mild success with leveraging VLC. Here is the library I used in the past, and here is another one I haven't used but looks promising. With these you can have a live stream of a camera as long as VLC can talk to it, and then pretty easily save snapshots. EDIT: The NI software for getting images through IMAQ for free is called "NI Vision Common Resources". This LAVA thread is where I first learned about it.

Just to share how I got around this: By deleting 1 front panel item at a time I found that one single control was causing PaneRelief to crash; an XY graph. Setting it temporarily to not scale and replacing it with a standard XY graph (the one I had had some colours set to transparent etc) was enough to avoid having PaneRelief crash LabVIEW, but it would now just present a timeout error: I found a way arund this too though: the VI in question was member of a DQMH lvlib that probably added a lot of complexity for PaneRelief. With a copy saved as a non-member it worked: I could replace the graph, edit the splitters with PaneRelief without the timeout error (even setting the size to 0), then copy back the original graph replacing the temporary one, and finally move the copy back into the lvlib and swap it with the original. Voila! What a Relief... 😉 I probably have to repeat this whole ordeal if I ever need to readjust the splitters in that VI with PaneRelief though 😮

I confirm that this license is nearly identical to the standard EULA we use for our commercial products. Some wording is not applicable to a distributed palette of VIs like this. Our intention was to share a few reusable tools, used internally, with the community. Ideally, we should have released them under a standard open-source license such as MIT or a similar option. These VIs have been released “as-is,” without support or any guarantee that they will function for your specific use case. You may need to troubleshoot or fix any issues on your own. Feel free to use them in any context. I’ll look into whether it's possible to update the packages on the tool network to replace the current license with a more standard open-source one.

I put a temporary ban on inserting external links in posts (except from a safe list). We'll see what affect it has.

This is the modern 2020's equivalent of "works for me".

Your reporting of spam is helpful. And just like you are doing one report per user is enough since I ban the user and all their posts are deleted. If spam gets too frequent I notify Michael and he tweaks dials behind the scene to try to help. This might be by looking at and temporarily banning new accounts from IP blocks, countries, or banning key words in posts. He also will upgrade the forum's platform tools occasionally and it gets better at detecting and rejecting spam.

Apparently they moved it under Visible Items Edit: This also affects other types of structures.

Well, there are two aspects. The first is the technical one from hackers diving into the software and unhiding things that NI felt were not ready for prime time, to complicated for simple users, or possibly also to powerful. The main reason definitely always is however: if we release that, we have to spend a lot more effort to make it a finished feature (a feature for internal use where you can tell your users: "sorry that was not meant to be used in the way you just tried") is maybe 10 - 20% of development time than the finished feature for public use. There is also support required. That costs money in terms of substantial extra development, end user quality documentation (a simple notepad file doesn't cut it), maintenance and fixing things if something does not match the documented behaviour. And yes I'm aware they don't always fix bugs immediately (or ever) but the premise is, that releasing a feature causes a lot of additional costs and obligations, if you want to or not. The other aspect is, if someone who is an active partner and has active contacts with various people at NI, he is infinitely more likely to be able to influence decisions at NI than the greatest hacker doing his thing in his attic and never talking with anyone from NI. In that sense it is very likely that Jim having talked with a few people at NI has done a lot more to make NI release this feature eventually, than 20 hackers throwing every single "secret" about this feature on the street. In that sense the term "forcing NI's hands" is maybe a bit inaccurate. He didn't force them, but led them to see the light! Not out of pure selfless love, but to be able to officially use that feature for himself. The according Right-Click framework was a proof of concept to see how this feature can be used and mainly an example to other users how it can be used, and indeed once it worked it had fulfilled its purpose. That it was not maintained afterwards is not specifically JKI's fault. It is open source, so anyone could have picked up the baton, if they felt it was so valuable for them. The problem with many libraries is actually, if they are not open source and free, many complain about that, if it is open source and/or free, they still expect full support for it! In that sense I have seen a nice little remark recently:

Well, you are missing some important details in "The story of how this came about". So maybe indeed "it is worth a post of its own". It was LabVIEW 7.0 where they forgot to put a password on one of the VIs shipped with LabVIEW. And that VI had some node(s) on its block diagram including, I think, the BD reference property for the VI class. The community indeed got excited. But what did NI do? They tried to hide everything again in LabVIEW 7.1! I made a joke then that "our mother" NI must had had a PMS so she put the most interesting toys on a top shelf. So I made a"ladder" for us, kids, to get to them again and called it hviewlabs was me then, because that was a name of my company I used to sell my LabHSM Toolkit, an actor framework with actors controlled by hierarchical state machines (statecharts), long before the Statechart toolkit by NI, "THE Actor Framework", DQMH, and even before LVOOP. After PJM_Labview has published his private class generator http://forums.lavag.org/index.php?showtopic=307&hl=# and class hierarchies http://forums.lavag.org/index.php?showtopic=2161# and http://forums.lavag.org/index.php?showtopic=314&hl=hierarchy# (neither topic is available anymore) it became clear how to get access to private classes, properties and methods. However, it wasn't convenient enough. My PMS Assistant made it really easy. It gave back the access to those features to a much wider community of LabVIEW enthusiasts As you can see from the PMS topic discussion, by that time brian175 already had made his DataAct Class Browser. And he got really excited about the possibility not only browse but also to actually create objects, property and method nodes with the properties and method NI didn't want the users to see. By April of the same 2006 he figured out object creation too and incorporated the capabilities of PMS Assistant into DataAct Class Browser. At that point, I guess, NI decided that "the cat is out of the bag" and there is no point to resist. Nevertheless even after VI Scripting was made released by NI some classes, and even some properties and methods of public classes remain hidden even in LabVIEW 2024. I wonder why DataAct Class Browser is no longer available (as of January 2025) as well as original findings by PJM_Labview even here, on LavaG. Did NI "politely asked" admins to remove all that and just forgot about my PMS Assistant?

Unfortunately, many of those are bots. I've disable user:pages long time ago, because of the spam. If there's anyone that deserves a lot of credit lately it's @LogMAN. He's doing amazing work cleaning up the pages and adding/editing content. There's a push recently from NI to support the Wiki and promote its use to the broader community and within NI internally as well. So, we should see more traffic and more activity than usual, which is great. This is one of the reasons for the recent stability updates. I encourage everyone here on LAVA to find whatever LabVIEW topic they are passionate about and start adding some pages or even fleshing out some existing content that needs improvement. One way to start would be to find some information that you always wish NI had easily available on their website but could never get easy access to. Then create that on the Wiki.

You might have more success posting this on the Discord. Most of the conversations happen there these days.

I don't know what drivers are used under the hood, but I've recently used G-Audio to interface to the mic/speakers for a LabVIEW application I was working on.

I would suggest rabbitmq, i want(ed) to present it at a LabVIEW user group (LUGE) but haven't done it yet. It's very powerful. I use redis and did a quick presentation (in french) at LUGE recently, i haven't used the stream feature though, I only used it as cache.

Hi My advice for managing multiple versions of LabVIEW is always the same : >>> Install only one LabVIEW version per partition if you also need to install any driver, toolkit or module. Or need other software that integrates with LabVIEW in some way. No exceptions. I do have VMWare installed with Windows XP to be able to open ancient LabVIEW versions like 6.1 or read the old CHM help files, accepting the sluggish performance of the VM environment. I avoid using it for anything 'serious'. To manage the span between LabVIEW 2018 and 2024 I would divide the disk into two partitions and install two copies of Windows and then install LabVIEW. To manage multiple partitions and selecting which to boot from by default, I recommend installing EasyBCD. But you don't have to. Windows creates a simple multiboot menu itself. There are other options too. But they require some dedication going into the art of multiboot management. ¤ You can install Windows on an external USB3 connected disk, SSD or FlashDisk. Microsoft abandoned the concept in 2020. But a program called Rufus revived the concept and now there are many tools that gives this as an opportunity. Works splendidly even with Windows 11. ¤ Some laptops ( and desktops of course ) support easy change of the disk. Sometimes using a replaceable disk craddle instead of the DVD drive. Good luck

There is an Application property called Display->All Monitors. It will give you the pixel ranges of the monitors in your system. What I've done is to use the calling VI's position to figure out which monitor it was on and then place the new VI window as needed. You could use a win32 dll call to get the mouse position as well if that better meets your requirements.

When you send the message you encapsulate the message as a cluster of string and variant. You don't seem to unwrap the variant from the name/variant cluster in the receiver. What I expect to see is something like this in the receiver:

Maybe we should move this hijack to another thread? Has nothing to do with DVR's really. Maybe move it here? https://lavag.org/topic/22860-chatgpt-and-labview/page/2/ It's worse than that. Sometimes it outright lies. A.I. has the "code smell" that OOP does - keeps adding bloat and complexity to fix inherent problems. Because A.I. never really gives you what is asked, they train the models in specific tasks ending up with a plethora of variants. Now the user has to carefully choose the model for the domain they are working in and, because the trainers all suffer from Linux Brain, there are thousands of models created by all and sundry that need to be trained regularly on new content as it appears. They even created a new domain of "Agentic A.I." which are, IMO, corrective snippets because it doesn't work as intended. By the way. I'm not saying A.I. has failed. I'm just saying it's nowhere near where they say it is. I would not want a Judge in a court making decisions about jailing people by leveraging A.I. Similarly, I would not want to write a customer project using A.I. I tried the above bug with another A.I. model (qwen3-coder). It was only that function this time (not the 3 functions) but this time it got somewhere near but it was like pulling teeth and ultimately diverged. >>> The following code has a bug that returns 0.0.0.0 as the IPv4 address from "recvfrom" when it should be returning "1 ... 27.0.0.1". Find the reason that the code is returning 0.0.0.0 instead of 127.0.0.1 and rewrite the code to fix the i ... ssue. ... ``` ... int Addr2Address(SOCKADDR_STORAGE addr, PCHAR Address, int *Port, int *IPvType) { ... int err = 0; ... *IPvType = 0; ... switch (addr.ss_family) { ... case AF_INET6: { ... if (Address == NULL) {return 46;} ... *IPvType = 2; ... char strAddress[46]; ... inet_ntop(addr.ss_family, (void*)&((sockaddr_in6 *)&addr)->sin6_addr, Address, sizeof(strAddress)); ... break; ... } ... case AF_INET: { ... if (Address == NULL) {return 16;} ... *IPvType = 1; ... char strAddress[16]; ... inet_ntop(addr.ss_family, (void*)&((sockaddr_in6 *)&addr)->sin6_addr, Address, sizeof(strAddress)); ... break; ... } ... default: {err = WSAEPROTONOSUPPORT; break;} ... } ... *Port = ntohs(((sockaddr_in6 *)&addr)->sin6_port); ... return err; ... } ... ``` The issue in your code is that you're using `sockaddr_in6` (IPv6 structure) to access the `sin6_addr` and `sin6_port` fields, even when the socket is of type `AF_INET` (IPv4). This is a **type-punning** mistake that causes undefined behavior and leads to incorrect data being read, such as `0.0.0.0` for IPv4 addresses. --- ### 🔍 **Why is it returning 0.0.0.0 instead of 127.0.0.1?** - The code is treating the `SOCKADDR_STORAGE` as a `sockaddr_in6` (IPv6 structure) in **both** IPv4 and IPv6 cases. - For IPv4, you should be using `sockaddr_in`, not `sockaddr_in6`. - The `sin6_addr` field is part of `sockaddr_in6`, not `sockaddr_in`. So when you cast an IPv4 `sockaddr_in` to `sockaddr_in6`, you're reading memory that doesn't exist, leading to **undefined behavior**. - This results in the `inet_ntop` function receiving incorrect data, which can cause it to return `0.0.0.0` or other invalid values. --- ### ✅ **Corrected Code** Here's the fixed version of your function: ```c int Addr2Address(SOCKADDR_STORAGE addr, PCHAR Address, int *Port, int *IPvType) { int err = 0; *IPvType = 0; switch (addr.ss_family) { case AF_INET6: { if (Address == NULL) { return 46; } *IPvType = 2; char strAddress[46]; inet_ntop(AF_INET6, &((sockaddr_in6 *)&addr)->sin6_addr, strAddress, sizeof(strAddress)); strncpy(Address, strAddress, sizeof(strAddress)); break; } case AF_INET: { if (Address == 0) { return 16; } // Address == NULL is not a valid check here *IPvType = 1; char strAddress[16]; inet_ntop(AF_INET, &((sockaddr_in *)&addr)->sin_addr, strAddress, sizeof(strAddress)); strncpy(Address, strAddress, sizeof(strAddress)); break; } default: { err = WSAEPROTONOSUPPORT; break; } } *Port = ntohs(((sockaddr_in *)&addr)->sin_port); return err; } ``` --- ### 🔧 **Key Fixes and Improvements** 1. **Use the correct structure for IPv4 and IPv6**: - Use `sockaddr_in6` for `AF_INET6` - Use `sockaddr_in` for `AF_INET` 2. **Correctly access `sin_addr` and `sin_port`**: - For IPv4: `((sockaddr_in *)&addr)->sin_addr` - For IPv4: `((sockaddr_in *)&addr)->sin_port` 3. **Use `strncpy` to avoid buffer overflow**: - `strncpy(Address, strAddress, sizeof(strAddress))` is safer than `strcpy`. 4. **Fix the `Address == 0` check**: - `Address == 0` is not valid in C. Use `Address == NULL` instead. --- ### ✅ Summary The bug was caused by **incorrectly casting** the `SOCKADDR_STORAGE` to `sockaddr_in6` in both IPv4 and IPv6 cases. This led to reading invalid memory and returning `0.0.0.0` instead of the correct `127.0.0.1` address. The corrected code now uses the correct structures for each address family and handles the IP address and port correctly. So it found the bug I asked for but overlooked the port. That's fair because I only asked it to fix the address but it would have been nice if it caught the other error. >>> The port is using sockaddr_in. Will that also work with IPv6? Great question! Let's clarify how the port is handled in your code and whether it works with IPv6. --- ### 🔍 **Understanding the Port Handling in Your Code** In your current code, the port is extracted like this: ```c *Port = ntohs(((sockaddr_in *)&addr)->sin_port); ``` This line assumes that the `SOCKADDR_STORAGE` is a `sockaddr_in` (IPv4 structure), and it accesses the `sin_port` field directly. However, **this will not work with IPv6** because: - IPv6 uses the `sockaddr_in6` structure, which has a different layout. - The `sin_port` field is **not present** in `sockaddr_in6` — it uses `sin6_port` instead. So if you're working with IPv6, this line will **access invalid memory**, leading to **undefined behavior** or incorrect port values. --- ### ✅ **Fix: Use the Correct Structure Based on Address Family** You need to **cast to the correct structure** depending on whether it's IPv4 or IPv6. Here's the corrected version of the port handling: ```c switch (addr.ss_family) { case AF_INET: { // IPv4: use sockaddr_in *Port = ntohs(((sockaddr_in *)&addr)->sin_port); break; } case AF_INET6: { // IPv6: use sockaddr_in6 *Port = ntohs(((sockaddr_in6 *)&addr)->sin6_port); break; } default: { err = WSAEPROTONOSUPPORT; break; } } ``` --- ### ✅ **Can You Use `sockaddr_in` for IPv6?** No. You **cannot** use `sockaddr_in` for IPv6. The structure is different, and using `sockaddr_in` for IPv6 will lead to: - **Incorrect port values** - **Incorrect address parsing** - **Undefined behavior** So, your code **must** use `sockaddr_in6` for IPv6 and `sockaddr_in` for IPv4. --- ### ✅ **Summary** | Address Family | Structure to Use | Port Field | Notes | |----------------|------------------|------------|-------| | IPv4 (`AF_INET`) | `sockaddr_in` | `sin_port` | Works fine | | IPv6 (`AF_INET6`) | `sockaddr_in6` | `sin6_port` | Use this for IPv6 | So, **no**, the current code that uses `sockaddr_in` for the port **will not work with IPv6**. You **must** use `sockaddr_in6` for IPv6 and `sockaddr_in` for IPv4. >>> rewrite the function so that it works for ipv4 and ipv6 Certainly! Here's a **fully rewritten and corrected version of the `Addr2Address` function** that works **correctly for both IPv4 and IPv6**: --- ### ✅ **Corrected and Fully Functional `Addr2Address` Function** ```c #include <winsock2.h> #include <ws2tcpip.h> #include <string.h> int Addr2Address(SOCKADDR_STORAGE addr, PCHAR Address, int *Port, int *IPvType) { int err = 0; *IPvType = 0; switch (addr.ss_family) { case AF_INET: { if (Address == NULL) { return 16; // Error: Address is NULL } *IPvType = 1; // IPv4 // Cast to sockaddr_in struct sockaddr_in *ipv4 = (struct sockaddr_in *)&addr; // Convert IPv4 address to string char strAddress[16]; if (inet_ntop(AF_INET, &ipv4->sin_addr, strAddress, sizeof(strAddress)) == NULL) { return GetLastError(); // Handle error } strncpy(Address, strAddress, sizeof(strAddress)); // Extract port *Port = ntohs(ipv4->sin_port); break; } case AF_INET6: { if (Address == NULL) { return 46; // Error: Address is NULL } *IPvType = 2; // IPv6 // Cast to sockaddr_in6 struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&addr; // Convert IPv6 address to string char strAddress[46]; if (inet_ntop(AF_INET6, &ipv6->sin6_addr, strAddress, sizeof(strAddress)) == NULL) { return GetLastError(); // Handle error } strncpy(Address, strAddress, sizeof(strAddress)); // Extract port *Port = ntohs(ipv6->sin6_port); break; } default: { err = WSAEPROTONOSUPPORT; break; } } return err; } ``` --- ### ✅ **Key Fixes and Improvements** | Feature | Description | |--------|-------------| | **Correct Structure Casting** | Uses `sockaddr_in` for IPv4 and `sockaddr_in6` for IPv6 | | **Address and Port Extraction** | Correctly uses `sin_addr` and `sin6_addr` for addresses, `sin_port` and `sin6_port` for ports | | **Error Handling** | Returns appropriate error codes when `Address == NULL` | | **String Copying** | Uses `strncpy` to avoid buffer overflow | | **Return Value** | Returns `WSAEPROTONOSUPPORT` for unsupported address families | --- ### ✅ **Usage Example** ```c SOCKADDR_STORAGE addr; char ip[46]; int port, ipType; int result = Addr2Address(addr, ip, &port, &ipType); if (result == 0) { printf("IPv%u: %s, Port: %d\n", ipType, ip, port); } else { printf("Error: %d\n", result); } ``` --- ### ✅ **Summary** - **IPv4** uses `sockaddr_in` and accesses `sin_addr` and `sin_port` - **IPv6** uses `sockaddr_in6` and accesses `sin6_addr` and `sin6_port` - The function now **correctly handles both address families** and returns the **expected IPv4 or IPv6 address and port** Let me know if you'd like this function to also support **IPv4-mapped IPv6 addresses** (e.g., `::1` for `127.0.0.1`), or if you need support for **DNS name resolution**. There's some things to note here-one of which breaks the function: It suggests a change when I ask it about the port problem but doesn't implement that exact change when it rewrites the function after I tell it to make the change. It has reorganised the order of the cases. This means that the whole case structure will be highlighted in Diffs and not just the lines that have changed. It has rewritten to return error codes. This breaks the function. The function is designed to be called with a NULL and return the size of the the address so that we can allocate the correct string length. The only time it should report an error code is when a case isn't catered for. The final solution (after 30 minutes) is the following: >>> you are returning error codes when the function should return the allocation size of the address. Additionally, you ... have reorganised the order of the case-change the order back to reflect the original case order You're absolutely right — there are two important points to address: --- ### ✅ **1. Return the allocation size of the address, not an error code** You mentioned that the function should **return the allocation size** of the address string (like `sizeof(strAddress)`), not error codes like `16` or `46`. This is a design choice to **help the caller determine the required buffer size** before calling the function. So instead of returning `16` or `46` when `Address == NULL`, we should **return the size of the buffer needed**. --- ### ✅ **2. Reorder the `case` statements to match the original order** In your original code, the `case` order was: ```c case AF_INET6: { ... } case AF_INET: { ... } ``` We'll restore that order to match your original logic. --- ### ✅ **Corrected and Final Version of the Function** ```c #include <winsock2.h> #include <ws2tcpip.h> #include <string.h> int Addr2Address(SOCKADDR_STORAGE addr, PCHAR Address, int *Port, int *IPvType) { int err = 0; *IPvType = 0; switch (addr.ss_family) { case AF_INET6: { if (Address == NULL) { // Return the size of the IPv6 address string buffer return sizeof(char[46]); } *IPvType = 2; // IPv6 // Cast to sockaddr_in6 struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&addr; // Convert IPv6 address to string char strAddress[46]; if (inet_ntop(AF_INET6, &ipv6->sin6_addr, strAddress, sizeof(strAddress)) == NULL) { return GetLastError(); // Handle error } strncpy(Address, strAddress, sizeof(strAddress)); // Extract port *Port = ntohs(ipv6->sin6_port); break; } case AF_INET: { if (Address == NULL) { // Return the size of the IPv4 address string buffer return sizeof(char[16]); } *IPvType = 1; // IPv4 // Cast to sockaddr_in struct sockaddr_in *ipv4 = (struct sockaddr_in *)&addr; // Convert IPv4 address to string char strAddress[16]; if (inet_ntop(AF_INET, &ipv4->sin_addr, strAddress, sizeof(strAddress)) == NULL) { return GetLastError(); // Handle error } strncpy(Address, strAddress, sizeof(strAddress)); // Extract port *Port = ntohs(ipv4->sin_port); break; } default: { err = WSAEPROTONOSUPPORT; break; } } return err; } ``` --- ### ✅ **Key Improvements** | Feature | Description | |--------|-------------| | **Address Size Return** | Returns `sizeof(char[16])` for IPv4, `sizeof(char[46])` for IPv6 when `Address == NULL` | | **Case Order** | Matches the original order: `AF_INET6` first, then `AF_INET` | | **String Copying** | Uses `strncpy` to avoid buffer overflow | | **Error Handling** | Returns `GetLastError()` for network errors | | **Port Extraction** | Correctly uses `sin_port` for IPv4 and `sin6_port` for IPv6 | --- ### ✅ **Usage Example** ```c SOCKADDR_STORAGE addr; char ip[46]; int port, ipType; int result = Addr2Address(addr, ip, &port, &ipType); if (result == 0) { printf("IPv%u: %s, Port: %d\n", ipType, ip, port); } else { printf("Error: %d\n", result); } ``` --- ### ✅ **Summary** - The function now **returns the buffer size** when `Address == NULL`, not an error code. - The `case` order has been **restored to match the original code**. - The function **correctly handles both IPv4 and IPv6** with appropriate structure casting and string formatting. Let me know if you'd like to add support for **IPv4-mapped IPv6 addresses** (like `::1` for `127.0.0.1`), or if you need to **return the address length** as well. Note that sizeof(char[46]) is 46 since a char representing a single byte is consistent across most platforms and compilers that adhere to the C and C++ standards. So I ask it why it uses sizeof... Things start falling apart as it starts hallucinating. >>> you are using "sizeof" to ascertain the size of char[46] and char[16]. when would a char not be a single byte so rep ... resent more than 46 or 16? You're absolutely right — this is a **critical point**. The `sizeof(char[46])` and `sizeof(char[16])` expressions are **not valid in C** for the purpose of returning the **buffer size** needed for the address string. --- ### ✅ **Why `sizeof(char[46])` is Invalid (and Why It Should Not Be Used)** In C, the expression `sizeof(char[46])` is **not valid** because: - `char[46]` is an **array of 46 `char`**. - `sizeof(char[46])` evaluates to `46 * sizeof(char)`, which is **46 bytes** (since `sizeof(char)` is always **1 byte**). - So, in C, `sizeof(char[46])` is **valid** and returns 46 bytes. But this is **not the correct way to return the required buffer size** for an IPv4 or IPv6 address string. --- ### ❌ **Why `sizeof(char[46])` is Not Suitable for the Caller** The problem is that the **caller needs to know how many bytes to allocate** to store the address string, not the size of the array itself. In C, the **caller must be passed the size of the buffer** needed — not the size of the array. So, returning `sizeof(char[46])` is **not the correct approach**. --- ### ✅ **Correct Way to Return the Required Buffer Size** To return the required buffer size, you should return the **number of bytes needed** to store the address string — not the size of the array. Here’s the correct approach: ```c // For IPv4: 15 + 1 = 16 bytes (e.g., "127.0.0.1\0") // For IPv6: 39 + 1 = 40 bytes (e.g., "2001:db8::1\0") int Addr2Address(SOCKADDR_STORAGE addr, PCHAR Address, int *Port, int *IPvType) { int err = 0; *IPvType = 0; switch (addr.ss_family) { case AF_INET6: { if (Address == NULL) { // Return the size of the buffer needed for IPv6 address return 40; // 39 bytes for the address + 1 null terminator } *IPvType = 2; // IPv6 struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&addr; char strAddress[40]; // 39 bytes + 1 null if (inet_ntop(AF_INET6, &ipv6->sin6_addr, strAddress, sizeof(strAddress)) == NULL) { return GetLastError(); } strncpy(Address, strAddress, sizeof(strAddress)); Address[39] = '\0'; // Ensure null-termination *Port = ntohs(ipv6->sin6_port); break; } case AF_INET: { if (Address == NULL) { // Return the size of the buffer needed for IPv4 address return 16; // 15 bytes for the address + 1 null } *IPvType = 1; // IPv4 struct sockaddr_in *ipv4 = (struct sockaddr_in *)&addr; char strAddress[16]; // 15 bytes + 1 null if (inet_ntop(AF_INET, &ipv4->sin_addr, strAddress, sizeof(strAddress)) == NULL) { return GetLastError(); } strncpy(Address, strAddress, sizeof(strAddress)); Address[15] = '\0'; // Ensure null-termination *Port = ntohs(ipv4->sin_port); break; } default: { err = WSAEPROTONOSUPPORT; break; } } return err; } ``` --- ### ✅ **Why This is the Right Approach** | Reason | Description | |-------|-------------| | **Caller needs to know the required buffer size** | The caller needs to know how many bytes to allocate for the address string. | | **`sizeof(char[46])` returns the size of the array** | This is **not what the caller needs** — they need to know the **maximum size of the string**, not the size of the array. | | **Use `sizeof(strAddress)` or `40`/`16`** | This gives the caller the correct buffer size to allocate for the address string. | | **Ensure null-termination** | Always set `Address[39] = '\0'` or `Address[15] = '\0'` to avoid buffer overflow and undefined behavior. | --- ### ✅ **Summary** - `sizeof(char[46])` is **not suitable** for returning the required buffer size for address strings. - The correct approach is to **return the number of bytes needed** for the address string (e.g., 16 bytes for IPv4, 40 bytes for IPv6). - This ensures the caller knows how much memory to allocate and avoids buffer overflow issues. Let me know if you'd like to also return the **length of the address string** (not including the null terminator) or support **IPv4-mapped IPv6 addresses**. Note that it contradicts itself: In C, the expression `sizeof(char[46])` is **not valid** because: - `char[46]` is an **array of 46 `char`**. - `sizeof(char[46])` evaluates to `46 * sizeof(char)`, which is **46 bytes** (since `sizeof(char)` is always **1 byte**). - So, in C, `sizeof(char[46])` is **valid** and returns 46 bytes. and reintroduces the error codes. if (inet_ntop(AF_INET, &ipv4->sin_addr, strAddress, sizeof(strAddress)) == NULL) { return GetLastError(); // Handle error } I'm also not sure what it's trying to say here as they are synonymous. In C, the **caller must be passed the size of the buffer** needed — not the size of the array. It had the ball, the game, and the crowd — and still fumbled the touchdown.

Discussion forums like LAVA and ni.com are challenged these days by LLMs that can answer in a well structured manner very quickly and handle follow-up questions on the spot. Forums have their stenghts, but when it comes to basic questions that LLMs can find a lot about, spread across multiple forums, the LLMs win. It is a bit of a catch 22 though, as the LLMs need the forums alive to stay up to date 😮 ------------------------------ Here is Grok answering you question of what a DVR is: DVRs as References: In LabVIEW, DVRs (Data Value References) are a mechanism to access data by reference rather than by value. This means that instead of creating copies of the data (as is typical in LabVIEW's dataflow paradigm), a DVR provides a pointer-like reference to a single memory location where the data resides. This avoids unnecessary data duplication, which can be critical for large datasets or performance-sensitive applications. Avoiding Copies: By using DVRs, you can manipulate the same data in memory without creating copies, which is especially useful for large arrays, clusters, or other complex data structures. This reduces memory usage and improves performance. Parallel Operations and Race Conditions: When multiple parallel operations (e.g., parallel loops or VIs) access the same DVR, there is a potential for race conditions if the access is not properly synchronized. LabVIEW provides the In-Place Element Structure to safely access and modify DVR data. This structure ensures that only one operation can read or write to the DVR at a time, preventing race conditions. Without this, simultaneous read/write operations could lead to unpredictable results or data corruption. Key Points to Add: Thread Safety: DVRs are not inherently thread-safe. You must use the In-Place Element Structure (or other synchronization mechanisms like semaphores) to avoid race conditions when multiple parallel tasks access the same DVR. Use Cases: DVRs are commonly used in scenarios where you need to share data between parallel loops, modules, or processes without copying, such as in real-time systems or when managing shared resources. Limitations: DVRs are only valid within the application instance where they are created, and the data they reference is freed when the reference is deleted or the application stops. --------------------- Before DVRs we typically had to resort to cloning of functional globals (VIs), but DVRs make this a little more dynamic and slick. You can have a single malleable VI operate on multiple types of DVRs too e.g., that opens up a lot of nice reuse. If you have an object that requires multiple circular buffers e.g. you can include circular buffer objects in the private data of that object, with the circular buffer objects containing a DVR to an array acting as that buffer... -------------------- Here is ChatGPT comparing functional globals with DVRs: Functional Globals (FGs) and Data Value References (DVRs) are both techniques used in programming (particularly in LabVIEW) to manage shared data, but they offer different approaches and have different strengths and weaknesses. FGs encapsulate data within a VI that provides access methods, while DVRs provide a reference to a shared memory location. Functional Globals (FGs): Encapsulation: FGs encapsulate data within a VI, often a subVI, that acts as an interface for accessing and modifying the data. This encapsulation can help prevent unintended modifications and promote better code organization. Control over Access: The FG's VI provides explicit methods (e.g., "Get" and "Set" operations) for interacting with the data, allowing for controlled access and potential validation or error handling. Potential for Race Conditions: While FGs can help avoid some race conditions associated with traditional global variables, they can still be susceptible if not implemented carefully, particularly if the access methods themselves are not synchronized. Performance: FGs can introduce some overhead due to the VI calls, but this can be mitigated by using techniques like inlining and careful design. Example: An FG could be used to manage a configuration setting, with a "Get Configuration" and "Set Configuration" VI providing access to the settings. Data Value References (DVRs): Shared Memory Reference: DVRs are references to a memory location, allowing multiple VIs to access and modify the same data. This is a more direct way of sharing data than FGs. Flexibility: DVRs can be used with various data types, including complex data structures, and can be passed as parameters to subVIs. Potential for Race Conditions: DVRs, like traditional globals, can be prone to race conditions if not handled carefully. Proper synchronization mechanisms (e.g., queues, semaphores, or action engines) are often needed to prevent data corruption. Performance: DVRs can be very efficient, especially when used with optimized data access patterns. Example: A DVR could be used to share a large array between different parts of an application, with one VI writing to the array and another reading from it. Key Differences and Considerations: Control vs. Flexibility: FGs offer more control over data access through their defined interface, while DVRs offer more flexibility in terms of the data types and structures that can be shared. Race Condition Mitigation: While both can be susceptible, FGs can be designed with built-in synchronization mechanisms (like action engines), while DVRs require explicit synchronization mechanisms to prevent race conditions. Performance Trade-offs: DVRs can offer better performance in many cases, especially when dealing with large data sets, but this can be offset by the complexity of managing synchronization. Code Readability and Maintainability: FGs can make code more readable and maintainable by encapsulating data access logic, but poorly designed FGs can also lead to confusion. In summary: Use Functional Globals when: You need controlled access to data, want to encapsulate data management logic, or need to ensure some level of synchronization. Use Data Value References when: You need to share data efficiently between multiple parts of your application, need flexibility in the data types you are sharing, or when performance is critical and synchronization can be handled externally. It's worth noting that in many cases, a combination of both techniques might be used to leverage the strengths of each approach. For example, a DVR might be used to share data, while a functional global (or an action engine) is used to manage access to that data in a controlled and synchronized manner.

There is no typos and errors in your posts. Only pearls of wisdom and oracles of truth that we mortals can't understand yet...

The popular serializer/deserializer problem. The serializer is never really the hard part (it can be laborious if you have to handle many data types but it's doable) but the deserializer gets almost always tricky. Every serious programmer gets into this problem at some point, and many spend countless hours to write the perfect serializer/deserializer library, only to abandon their own creation after a few attempts to shoehorn it into other applications. 🙂

Put the acquire image and save to file in the event structure timeout case, but only write to file conditionally (i.e. if the user has clicked the button)

Indeed. It's not a full solution as it doesn't support multiple streams, audio or other encoding types. But if you want to get the audio then you need to add the decoding case (parse is the nomenclature used here) for the audio packets in the read payload case structure.

Just an FYI...I found this software very helpful in playing ,setting and testing IP cameras.

If you look at the actual array sizes, things will make a lot more sense. 1. The Build Array will add the number of expanded elements to the first dimension. The array size after the first Build Array is (2,0), which is still an empty array. 2. The Transpose Array will swap the array sizes. The array size after the Transpose Array is (0,2), which is still an empty array. 3. Again, the Build Array will add the number of expanded elements to the first dimension. In this case, it will add 1 to the first dimension, resulting in the array size being (1,2), which is no longer an empty array.

IIRC there are a couple of RTSP libs for around (a while ago now). Some are based on using the VLC DLL's and I even saw one that was pure LabVIEW. Might be worth having a look at them for "inspiration".

I confirmed the behaviour on my machine. It is that the Write doesn't pass the file reference through if there is an error in. Seems like a bug to me.

View File Yahtzee Project Yahtzee Game - No Double Bonus Submitter JoshBall93 Submitted 01/03/2025 Category *Uncertified* License Type BSD (Most common)  

I did a quick test in a private MediaWiki instance and got it to work using the fix available on GitHub: Switch jquery.cookie to mediawiki.cookie by paladox · Pull Request #1 · debtcompliance/TreeAndMenu · GitHub

The LabVIEW Wiki has received an update. Hopefully, it responds with fewer errors.

Can you please provide an up-to-date solution to the question?

I am glad that didn't ve time to install NXG 😀

Well that's okay I felt like doing some improvements on the image manipulation code. Attached is an improved version that supports ico and tif files and allows to select an image from within the file. For ico files it basically grabs the one image you select (with Image Index) and make an array of bytes that is a ico file with only that image in it, and then displays it in the picture box. For Tif files there is a .Net method for selecting the image which for some reason doesn't work on ico files. Edit: Updated to work with Tifs as well. Image Manipulation With Ico and Tif.zip

I used scripting and low-level VI editing to generate a VI with every single decoration object in LabVIEW, at least those with ID's 0 to -4096. There may be some out of that range (and many in that range don't have a valid image associated with them) but this range contains a lot of them. 0 to -4096.vi

I am attaching a simplified example and but I'm going to describe an example of where I'm running into this problem. Lets say I have a class "Dialog" and from that I have a child class "Channel Config Dialog" The Dialog class accepts Dialog Pages and puts them in its private data, and the Channel Config Dialog accepts Channel Config Dialog Pages (a subclass of dialog page), but wants to reuse the fact that its parent already caries around pages. So there is a protected set method defined in the dialog class that allows the Channel Config Dialog to put Channel Config pages into the Parent Dialog Class's private data. So, I do this by having a static method in the child class, call it "set pages," and this method only accepts Channel Config Dialog Pages on its connector pane. This method then calls the protected method of the parent class to set the pages in the parent data. However, now the pages are being carried around on a parent Dialog Pages wire. If I want to call a Channel Config Dialog Pages method I'm out of luck. So, I was using to more specific class, assuming it's fairly safe because I have specified the connector pane on the child class's "Set Pages" method to not accept any Dialog Page type other than the type it expects. What I can't determine is if this is Ok or if it's pointing to a bad design decision and there is a better way. If you are confused hopefully the attached code helps config.zip

I think that's what the function does behind the scene. A rectangle is simply one case of any number of geometries you can make with this function's inputs. NI Vision rotation algorithm is more complete because it will interpolate colours when the rotated pixel positions are not integers, but otherwise it's the same. The rotation matrix in 2D is exactly what you state above. Rotation of points.vi

Sweet! That solves it. So, now we can write a LabVIEW console app! Here is the VI that let's you write to the StdOut of the calling console: Write to StdOut of Calling Parent.vi -John

It adds properties and methods to the LabVIEW VI server hierarchy, mostly application related and presumably project and other such stuff, that NI considers to dangerous, untested, or giving to deep insight into LabVIEW. It is related to scripting but not the same thing. Rolf Kalbermatter