AudioComponentCount not finding AUs - macos

I'm trying to update a simple sequencer I wrote a few years ago in XCode 3. I hit a brick wall at the very outset because AudioComponentCount and AudioComponentFindNext do not find my software instruments.
They just find two: Apple's DLS music device and their sampler.
I have several others which I can see in the library Components file. Auval sees them too, and passes them OK. They also work fine with my old sequencer, where they are found OK by the same functions. And I have checked that the components are up to date.
I do have the AudioUnits framework linked in (and the program compiles OK, it just doesn't do the right thing). Trying CountComponents with the CoreServices famework gives the same problem.
All the Apple documentation and sample code I have found indicates that my code should work.
Can someone suggest why these functions should be blind to perfectly good synths?
(I am compiling using XCode 4.3.3 on a Mac Quad-core Intel Xeon running Mac OS X 10.7.5. Could it be incompatibility between the up-to-date XCode and the Lion OS??)

Related

Simple HID OSX Application

I am getting started with coding for HID devices. I got started with reading Apple documents and sample code. The code provided are terribly outdated that it doesn't even open in Xcode8.
Download Sample Code from Apple
I need help in finding a sample project / snippet for getting started with HID Services! Open a handle, read and write reports to device, Listen to reports generated by device in a run loop.
OS X/macOS's HID stack is called IOHIDFamily, and much of it is open source. This includes kernel and userspace components. You can find the code for various different OS X/macOS releases at
https://opensource.apple.com/
For 10.12.2 (latest code released at time of writing) you can browse the IOHIDFamily code here:
https://opensource.apple.com/source/IOHIDFamily/IOHIDFamily-870.31.1/
or download it as a zip file here:
https://opensource.apple.com/tarballs/IOHIDFamily/IOHIDFamily-870.31.1.tar.gz
The "tools" directory contains some userspace sample/test code which might help with what you're trying to do.
As for sample code not being updated, documentation being incomplete/outdated/missing, and provided code requiring a lot of effort to build: welcome to Mac systems & driver development. That's unfortunately how it is. I've been doing OS X kernel/driver work for 7 years, and while some things get easier with experience, downloading code from Apple and building it still feels like playing the lottery.

EXC_BAD_ACCESS from Canon's EDSDK EdsInitializeSDK() API

I'm writing a camera control program in Xcode 7.2 on OS X 10.11.2 and every once and a while my program will crash at EdsInitializeSDK(). Most of the solutions online suggest downloading other EDSDK.framework file, but this hasn't worked for me. Also, most of the solutions were written almost 3 years ago.
The thing that doesn't make sense to me is that the program runs most of the time and only occasionally crashes. Has anyone found a work around to prevent the bad access?
This seems to be related to an incompatibility between OSX 10.11+ El Capitan and the "older" EDSDKs, for us when using it in combination with swift. It seems not to be a problem in OSX 10.10 Yosemite. Canon EOS Utility, and other pure objective-c / C++ are mostly unaffected by this. I can confirm that EDSDK 3.4, released Apr 8 2016, includes fixes in this area.

confusion of how to make osx app backward compatible & how to test them

after reading the apple SDK guide
https://developer.apple.com/library/mac/#documentation/developertools/conceptual/cross_development/Overview/overview.html
I'm still confused of how to make the mac app backward compatible & how to test them properly
I have an app, I run it and tested it on Mountain Lion 10.8 without any problem, however I want to make this app backward compatible so that other users can run it on a mac 10.6 - 10.7 machine.
I have an apple developer id and I can download the old versions of 10.7 and 10.6, but the problem is, I have a 2011 macbook air which is currently running 10.8, and that's the only apple machine that I have. Can I test the 10.7 and 10.6 by using vmware or parallels?
in my project settings, I set the target deployment to 10.6 (as I want 10.6 users to run my app), but should I set my SDK to 10.8 or 10.7? if I set the SDK to 10.8 but having the target deployment set to 10.6, if I fix all the xcode warnings will it run successfully on 10.6??
from the SDK drop down, I can only set to 10.8 or 10.7, but 10.6 is missing, how do I fix that?
thanks in advance
I develop on a 10.8 box and support back to 10.5. Just a couple of months ago we dropped 10.4 PPC support, and I'm still cleaning out some of the 10.2-specific code. This may get a little rant-y, but I've been doing old versions for a long time. I have some opinions on the matter.
No matter what Apple says in their docs, if you want to support 10.6, then build with the 10.6 SDK. Do not rely on distribution target.
I have had this discussion with the Xcode engineers, and while they hold to Apple's party line that you should always build with the latest SDK, they also acknowledge that it's generally insane to do so. If you build against the 10.8 SDK and mark your deployment target at 10.6, you will get no warnings for using methods that do not exist on 10.6. The only way you will discover that you've used a nonexistent method is that it might give you strange bugs when run on 10.6. That's insane.
Remember, OS X doesn't crash when you send an unknown selector. It just aborts the current runloop. So the bugs are even harder to track down then on iOS, where it crashes the app.
Sure, you can do weak linking. Talk about dangerous.... Yes, there are a few times this is useful, but the compiler gives you no warning if you don't do it correctly. If I'm going to do weak linking like this, I go the other way, linking against the old SDK and copying the new function's prototype into my implementation. That way I have documentation of every function I think I'm going to weak-link.
Download the old SDKs and symlink them into your Xcode distribution.
Guard them jealously. Apple will try to delete them every time you upgrade Xcode. Make your own copies and stick them in /SDKs or somewhere else away from Xcode. I provide a script called fix-xcode to manage the symlinks automatically. Am I bitter at Apple for their relentless insistance on deleting my old SDKs? Yes, I am.
You can run 10.6 Server in a VM legally. You can run 10.7+ Desktop in a VM legally. These are good ways to test your code.
Or you can do what I do and have a small pile of old MacBooks each with two or three partitions on them that you reboot all the time.
Now that 10.7 comes from App Store, it's a little harder to make VMs. My strong recommendation is to snapshot your image immediately after install, and make a clean backup copy of it. You'll want to be able to clone that image from time to time when you need to get back to a "raw" machine.
Get in the habit of squirreling away SDKs as they come out. 10.8 will be old some day. You might as well make a copy now while it's easy.
Whether you support individual dot-releases or not, it can be very helpful to keep around the upgrade packages for individual dot releases. When you encounter customers running non-current releases, it's nice to be able to check whether an "unreproducible" bug in fact is easily reproducible on their specific version. Whether this is worth it or not depends heavily on your product and customers. It was a life-saver for me when 10.4.11 made major changes to WebKit during a dot release...
Invest in a small NAS or a big external USB drive (though I've had trouble with those failing when used extensively, so I prefer a RAID). You'll need the space. You want to hold onto lots of VMs and lots of SDKs and sometimes even old versions of Xcode.
Adding to Rob Napier's great in-depth answer:
To use an old SDK, put the SDK (or a symlink) to it here:
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs
With XCode 7.3 or later, you need you to open this file and change "MinimumSDKVersion" (otherwise XCode will refuse to use the old SDK):
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Info.plist
You can install multiple versions of Mac OS on a single machine, booting between each.
The SDK should be the latest (10.8).
See 2.
One alternative to 1 that I've considered (I am in the same boat) is to create a Snow Leopard Hackintosh using an old PC and just installing Lion and Mountain Lion on my MBP.
You need to do these settings :
1.Set the Base SDK to Current version of Mac (ex. 10.7)
2.Set the Deployment SDK to older version (ex.1.4)

Writing code for a Mac using Lazarus

I have done a little work on lazarus' free pascal. So when a client asked me to write an application for a mac, after the initial, "it can't be done" stage. (followed by an asp.net maybe stage) i thought about writing it using lazarus.
Question is. I have only a virtual machine running mac OSX, this means that i do not really want to develop on the mac. However, i just cannot seem to get the applications that i have written in lazarus on windows to work on the mac. I have tried the deployment using the Lazarus Wiki and the MACOS folder is empty and so when i put it on the mac it doesn't run the application.
What is the best way of doing this or am i barking up the wrong tree?
It seems you want to do cross-compiling, which is theoretically possible, but may not be practical, for the reasons mentioned by Marco above.
As an alternative, you could install XCode, FreePascal, and Lazarus on a MacOX machine. You could still do your development and some testing on Windows/Linux. When you hit a certain milestone, you can copy your source code to the Mac and compile your application to test and give to the user.
Even if it were possible to easily cross-compile, there some minor differences between platforms, so (especially if it's a GUI app), you would want to test it on an actual MacOS box before giving it to the client.
I've taken the route described by Noah - and I was incredibly surprised that after about three weeks development on Windows, it took about 10 minutes to get the application running on the Mac.
My route was to install Xcode 4.3 on an old Mac Mini running snow leopard, then install Lazarus using the fink version as described here. This took a while but was done in an evening.
Then I just copied my folder across to the Mac, opened the lpi on the Mac, compiled it. It failed so I removed a windows references, recompiled, and it was working. I was truly amazed.
What linker and assembler do you use to generate binaries? To my best knowledge the linker for recent OS X versions is not available in source.
Afaik what you want (crosscompiling to Mac) is not possible for recent versions (and I've done it for PowerPC myself in the past).
The easiest is to use the Unix "file" command on the binary to see what is generated, and make sure it reads something with "MachO" in it. Easiest is if you have a Linux install (where this command is pretty standard), but versions can be found for windows too (cygwin, mingw and 3rd party)

Test build of Cocoa application not compatible with tester's version of OS X

I've been building a basic Cocoa application with Core Data and Interface Builder, and no extra coding, frameworks, or header files. I sent it to someone to test on their machine (a last-gen G5 iMac), and they got a message saying that their machine couldn't run it. I discovered the switch to compile for PPC, so I built a PPC version of the application to try out, and that produced the following error message:
You cannot use this version of Application on this version of Mac OS X.
I'm running Xcode 3.2.1, Interface Builder 3.2.1, and OS 10.6.2. The conversation with my tester was a bit confusing; at first it sounded like she only had Tiger on her machine, saying Leopard was incompatible (I corrected and said that Leopard should be, it's Snow Leopard that isn't), and then by the end of the conversation she was about certain that her machine was running Leopard, but had already shut it off by then. So I'm not sure which version of OS X is on the offending iMac, but it's the latest version of either 10.4.11 or 10.5.8 (the tester is in a remote location, so I can't verify personally at the moment).
What can I tweak to try and improve compatibility on my tester's machine?
If they're seeing that message, it's most likely because your app has the LSMinimumSystemVersion key (Minimum system version) set in the Info.plist. You should take this key out or set it to the actual the minimum OS X version you support.
Once you do this, you may well run into the next problem. (Probably a dynamic linker error as a result of using a framework or API that didn't yet exist on 10.4 or 10.5.)
The main problem here is that you're sending it out to a system where you haven't actually tried it. If you plan to support 10.4, 10.5, or both, I highly recommend that you find a spare hard drive, partition it up, and install 10.4.11 and 10.5.8. There are many issues that will crop up on older OS's and if you haven't tried it yourself, it's unlikely it will work smoothly on the first try.

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