In this thread https://developer.apple.com/forums/thread/705281 (which I am the original poster), I have marked my own post as the accepted answer. I did that before I got input from Quinn on how to achieve what I was after. I have posted that information in a subsequent post in that thread here https://developer.apple.com/forums/thread/705281?answerId=712746022#712746022. Can someone please mark this as the correct answer? I tried but I don't see any option to do it myself. P.S: In some forum threads, I see that things like these are sorted through direct messages sometimes. But I can't see any place in my profile where I can send a direct message from. Does that feature require some level of forum points?

Consider this very trivial code which accesses the operatingSystemVersion property of NSProcessInfo as documented at https://developer.apple.com/documentation/foundation/nsprocessinfo/1410906-operatingsystemversion osversion.c: #include <Foundation/Foundation.h> int main(int argc, char *argv[]) { NSOperatingSystemVersion osVersion = [[NSProcessInfo processInfo] operatingSystemVersion]; fprintf(stderr, "OS version: %ld.%ld.%ld\n", osVersion.majorVersion, osVersion.minorVersion, osVersion.patchVersion); } Compile it: /usr/bin/clang -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX13.1.sdk -iframework /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX13.1.sdk/System/Library/Frameworks -x objective-c -o a.out -framework Foundation osversion.c Then run it: ./a.out It works fine and prints the OS version: OS version: 14.6.1 Run it again and pass it some arbitrary program arguments: ./a.out foo bar Still continues to work fine and prints the output: OS version: 14.6.1 Now run it again and this time pass it two program arguments, the first one being - and the second one being something of the form {x=y} ./a.out - {x=y} This time notice how it prints a couple of warning logs from CFPropertyListCreateFromXMLData before printing the output: 2024-10-11 11:18:03.584 a.out[61327:32412190] CFPropertyListCreateFromXMLData(): Old-style plist parser: missing semicolon in dictionary on line 1. Parsing will be abandoned. Break on _CFPropertyListMissingSemicolon to debug. 2024-10-11 11:18:03.585 a.out[61327:32412190] CFPropertyListCreateFromXMLData(): Old-style plist parser: missing semicolon in dictionary on line 1. Parsing will be abandoned. Break on _CFPropertyListMissingSemicolon to debug. OS version: 14.6.1 As far as I can see there's nothing wrong in the code nor the user inputs to the program. Is this some issue in the internal implementation of NSProcessInfo? Should this be reported as an issue through feedback assistant (which category)? Although this example was run on 14.6.1 of macos, the issue is reproducible on older versions too.

A few minutes back I filed a feedback assistant issue for this (FB18173706), but I am not sure I filed it in the correct category and I can't find a way to edit it either. So posting this message here just to have to assigned in the right category if appropriate. The issue is as follows. On macOS 26 Tahoe Beta, "man sw_vers" has this among other details: Previous versions of sw_vers respected the SYSTEM_VERSION_COMPAT environment variable to provide compatibility fallback versions for scripts which did not support the macOS 11.0+ version transition. This is no longer supported, versions returned by sw_vers will always reflect the real system version. It says that SYSTEM_VERSION_COMPAT is no longer supported. That doesn't look right, because running sw_vers as follows on macOS 26 Beta results in: SYSTEM_VERSION_COMPAT=1 sw_vers ProductName: macOS ProductVersion: 16.0 BuildVersion: 25A5279m i.e. setting the environment variable SYSTEM_VERSION_COMPAT=1 results in sw_vers reporting the version as 16.0. Now try with SYSTEM_VERSION_COMPAT=0, and the result is: SYSTEM_VERSION_COMPAT=0 sw_vers ProductName: macOS ProductVersion: 26.0 BuildVersion: 25A5279m notice the output says 26.0. So it appears that SYSTEM_VERSION_COMPAT is supported even on macOS 26. I think the man page requires an update to match this behaviour.

We have been observing an issue where when binding a UDP socket to an ephemeral port (i.e. port 0), the OS ends up allocating a port which is already bound and in-use. We have been seeing this issue across all macos versions we have access to (10.x through recent released 13.x). Specifically, we (or some other process) create a udp4 socket bound to wildcard and ephemeral port. Then our program attempts a bind on a udp46 socket with ephemeral port. The OS binds this socket to an already in use port, for example you can see this netstat output when that happens: netstat -anv -p udp | grep 51630 udp46 0 0 *.51630 *.* 786896 9216 89318 0 00000 00000000 00000000001546eb 00000000 00000800 1 0 000001 udp4 0 0 *.51630 *.* 786896 9216 89318 0 00000 00000000 0000000000153d9d 00000000 00000800 1 0 000001 51630 is the (OS allocated) port here, which as you can see has been allocated to 2 sockets. The process id in this case is the same (because we ran an explicit reproducer to reproduce this), but it isn't always the case. We have a reproducer which consistenly shows this behaviour. Before filing a feedback assistant issue, I wanted to check if this indeed appears to be an issue or if we are missing something here, since this appears to be a very basic thing.

I am looking at some logs that I collected through sysdiagnose and I notice several messages of the form: ... fault 2025-03-05 01:12:04.034832 +0000 runningboardd Two equal instances have unequal identities. <anon<java>(502) pid=86764 AUID=502> and <anon<java>(502)(0) pid=86764> fault 2025-03-05 01:15:05.829696 +0000 runningboardd Two equal instances have unequal identities. <anon<java>(502) pid=88001 AUID=502> and <anon<java>(502)(0) pid=88001> fault 2025-03-05 01:15:06.047003 +0000 runningboardd Two equal instances have unequal identities. <anon<java>(502) pid=88010 AUID=502> and <anon<java>(502)(0) pid=88010> fault 2025-03-05 01:15:06.385648 +0000 runningboardd Two equal instances have unequal identities. <anon<java>(502) pid=88012 AUID=502> and <anon<java>(502)(0) pid=88012> fault 2025-03-05 01:15:07.135896 +0000 runningboardd Two equal instances have unequal identities. <anon<java>(502) pid=88019 AUID=502> and <anon<java>(502)(0) pid=88019> fault 2025-03-05 01:15:07.491316 +0000 runningboardd Two equal instances have unequal identities. <anon<java>(502) pid=88021 AUID=502> and <anon<java>(502)(0) pid=88021> fault 2025-03-05 01:15:07.542102 +0000 runningboardd Two equal instances have unequal identities. <anon<java>(502) pid=88022 AUID=502> and <anon<java>(502)(0) pid=88022> fault 2025-03-05 01:15:07.803126 +0000 runningboardd Two equal instances have unequal identities. <anon<java>(502) pid=88025 AUID=502> and <anon<java>(502)(0) pid=88025> fault 2025-03-05 01:15:59.774214 +0000 runningboardd Two equal instances have unequal identities. <anon<java>(502) pid=88568 AUID=502> and <anon<java>(502)(0) pid=88568> fault 2025-03-05 01:16:00.142288 +0000 runningboardd Two equal instances have unequal identities. <anon<java>(502) pid=88572 AUID=502> and <anon<java>(502)(0) pid=88572> fault 2025-03-05 01:16:00.224019 +0000 runningboardd Two equal instances have unequal identities. <anon<java>(502) pid=88573 AUID=502> and <anon<java>(502)(0) pid=88573> fault 2025-03-05 01:16:01.180670 +0000 runningboardd Two equal instances have unequal identities. <anon<java>(502) pid=88580 AUID=502> and <anon<java>(502)(0) pid=88580> fault 2025-03-05 01:16:01.879884 +0000 runningboardd Two equal instances have unequal identities. <anon<java>(502) pid=88588 AUID=502> and <anon<java>(502)(0) pid=88588> fault 2025-03-05 01:16:02.233165 +0000 runningboardd Two equal instances have unequal identities. <anon<java>(502) pid=88589 AUID=502> and <anon<java>(502)(0) pid=88589> ... What's strange is that each of the message seems to say that it has identified two instances with unequal identities and yet it prints the same process for each such message. Notice: fault 2025-03-05 01:16:02.233165 +0000 runningboardd Two equal instances have unequal identities. <anon<java>(502) pid=88589 AUID=502> and <anon<java>(502)(0) pid=88589> I suspect the identity it is talking about is the one explained as designated requirement here https://developer.apple.com/documentation/Technotes/tn3127-inside-code-signing-requirements#Designated-requirement. Yet the message isn't clear why the same process would have two different identities. The type of this message is "fault", so I'm guessing that this message is pointing to some genuine issue with the executable of the process. Is that right? Any inputs on what could be wrong here? This is from a 15.3.1 macosx aarch64 system. On that note, is runningboardd the process which is responsible for these identity checks?

I've been investigating an issue with the SO_OOBINLINE socket option. When that option is disabled, the expectation is that out-of-band data that is sent on the socket will not be available through the use of read() or recv() calls on that socket. What we have been noticing is that when the socket is bound to a non-loopback address (and the communication is happening over that non-loopback address), then even when SO_OOBINLINE is disabled for the socket, the read()/recv() calls both return the out-of-band data. The issue however isn't reproducible with loopback address, and read()/recv() both correctly exclude the out-of-band data. This issue is only noticed on macos. I have been able to reproduce on macos M1, following version, but the original report which prompted me to look into this was reported on macos x64. My M1 OS version is: sw_vers ProductName: macOS ProductVersion: 14.3.1 BuildVersion: 23D60 Attached is a reproducer (main.c.txt - rename it to main.c after downloading) that I have been able to develop which reproduces this issue on macos. When you compile and run that: ./a.out it binds to a non-loopback address by default and you should see the failure log, resembling: ... ERROR: expected: 1234512345 but received: 12345U12345 To run the same reproducer against loopback address, run it as: ./a.out loopback and that should succeed (i.e. no out-of-band data) with logs resembling: ... SUCCESS: completed successfully, expected: 1234512345, received: 1234512345 Is this a bug in the OS? I would have reported this directly through feedback assistant, but my past few open issues (since more than a year) have not even seen an acknowledgement or a reply, so I decided to check here first. main.c.txt

I am in the middle of investigating an issue arising in the call to setsockopt syscall where it returns an undocumented and unexpected errno. As part of that, I'm looking for a way to list any socket content filters or any such extensions are in play on the system where this happens. To do that, I ran: systemextensionsctl list That retuns the following output: 0 extension(s) which seems to indicate there's no filters or extensions in play. However, when I do: netstat -s among other things, it shows: net_api: 2 interface filters currently attached 2 interface filters currently attached by OS 2 interface filters attached since boot 2 interface filters attached since boot by OS ... 4 socket filters currently attached 4 socket filters currently attached by OS 4 socket filters attached since boot 4 socket filters attached since boot by OS What would be the right command/tool/options that I could use to list all the socket filters/extensions (and their details) that are in use and applicable when a call to setsockopt is made from an application on that system? Edit: This is on a macosx-aarch64 with various different OS versions - 13.6.7, 14.3.1 and even 14.4.1.

Continuing with my investigations of several issues that we have been noticing in our testing of the JDK with macosx 15.x, I have now narrowed down at least 2 separate problems for which I need help. For a quick background, starting with macosx 15.x several networking related tests within the JDK have started failing in very odd and hard to debug ways in our internal lab. Reading through the macos docs and with help from others in these forums, I have come to understand that a lot of these failures are to do with the new restrictions that have been placed for "Local Network" operations. I have read through https://developer.apple.com/documentation/technotes/tn3179-understanding-local-network-privacy and I think I understand the necessary background about these restrictions. There's more than one issue in this area that I will need help with, so I'll split them out into separate topics in this forum. That above doc states: macOS 15.1 fixed a number of local network privacy bugs. If you encounter local network privacy problems on macOS 15.0, retest on macOS 15.1 or later. We did have (and continue to have) 15.0 and 15.1 macos instances within our lab which are impacted by these changes. They too show several networking related failures. However, I have decided not to look into those systems and instead focus only on 15.3.1. People might see unexpected behavior in System Settings > Privacy & Security if they have multiple versions of the same app installed (FB15568200). This feedback assistant issue and several others linked in these documentations are inaccessible (even when I login with my existing account). I think it would be good to have some facility in the feedback assistant tool/site to make such issues visible (even if read-only) to be able to watch for updates to those issues. So now coming to the issue. Several of the networking tests in the JDK do mulicasting testing (through BSD sockets API) in order to test the Java SE multicasting socket API implementations. One repeated failure we have been seeing in our labs is an exception with the message "No route to host". It shows up as: Process id: 58700 ... java.net.NoRouteToHostException: No route to host at java.base/sun.nio.ch.DatagramChannelImpl.send0(Native Method) at java.base/sun.nio.ch.DatagramChannelImpl.sendFromNativeBuffer(DatagramChannelImpl.java:914) at java.base/sun.nio.ch.DatagramChannelImpl.send(DatagramChannelImpl.java:871) at java.base/sun.nio.ch.DatagramChannelImpl.send(DatagramChannelImpl.java:798) at java.base/sun.nio.ch.DatagramChannelImpl.blockingSend(DatagramChannelImpl.java:857) at java.base/sun.nio.ch.DatagramSocketAdaptor.send(DatagramSocketAdaptor.java:178) at java.base/java.net.DatagramSocket.send(DatagramSocket.java:593) (this is just one example stacktrace from java program) That "send0" is implemented by the JDK by invoking the sendto() system call. In this case, the sendto() is returning a EHOSTUNREACH error which is what is then propagated to the application. The forum text editor doesn't allow me to post long text, so I'm going to post the rest of this investigation and logs as a reply.

Is there any recent and a bit authoritative documentation which explains how to debug recent versions of macos kernel? I have found some blog posts from other users but those are either outdated or don't work for some other reason. I am guessing kernel debugging is pretty common for developers working on macos itself, so I'm hoping someone in this forum would have some working instructions for that.

Around a month back, developers of the OpenJDK project, when using XCode 16 to build the JDK started noticing odd failures when executing code which was compiled using the clang++ compiler shipped in that XCode 16 release (details in https://bugs.openjdk.org/browse/JDK-8340341). Specifically, a trivial for loop in a c++ code of the form: int limit = ... // method local variable for (i=0; i<limit; i++) { ... } ends up iterating more times than the specified limit. The "i<limit" returns true even when it should have returned false. In fact, debug log messages within the for loop of the form: fprintf(stderr, "parsing %d of %d, %d < % d == %s", i, limit, i, limit, (i<limit) ? "true" : "false"); would show output of the form: parsing 0 of 2, 0 < 2 == true parsing 1 of 2, 1 < 2 == true parsing 2 of 2, 2 < 2 == true Notice, how it entered the for loop even when 2 < 2 should have prevented it from entering it. Furthermore, notice the message says 2 < 2 == true (which clearly isn't right). This happens when that code is compiled with optimization level -O2 or -O3. The issue doesn't happen with -O1. I had reported this as an issue to Apple through feedback assistance, more than a month back. The feedback id is FB15162411. There hasn't been any response to it nor any indication that the issue has been noticed and can be reproduced (the steps to reproduce have been provided in that issue). In the meantime, more and more users are now running into this failure in JDK when using XCode 16. We haven't put any workaround in place (the only workaround we know of is using -O1 for the compilation of this file) because it isn't clear what exactly is causing this issue (other than the fact that it shows up with specific optimization levels). It's also unknown if this bug has wider impact. Would it be possible to check if FB15162411 is being looked into and any technical details on what's causing this? That would help us decide if it's OK to put in place a temporary workaround in the OpenJDK build and how long to maintain that workaround. For reference, this was reproduced on: clang++ --version Apple clang version 16.0.0 (clang-1600.0.26.3) Target: arm64-apple-darwin23.6.0 Thread model: posix InstalledDir: /xcode-16/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin

I am looking for inputs to better understand MacOS entitlements. I ask this in context of OpenJDK project, which builds and ships the JDK. The build process makes uses of make tool and thus doesn't involving building through the XCode product. The JDK itself is a Java language platform providing applications a set of standard APIs. The implementation of these standard APIs internally involves calling platform specific native library functions. In this discussion, I would like to focus on the networking functions that the implementation uses. Almost all of these networking functions and syscalls that the internal implementation uses are BSD socket related. Imagine calls to socket(), connect(), getsockopt(), setsockopt(), getaddrinfo(), sendto(), listen(), accept() and several such. The JDK that's built through make is then packaged and made available for installation. The packaging itself varies, but for this discussion, I'll focus on the .tar.gz archived packaging. Within this archive there are several executables (for example: java, javac and others) and several libraries. My understanding, based on what I have read of MacOS entitlements is that, the entitlements are set on the executable and any libraries that would be loaded and used by that executable will be evaluated against the entitlements of the executable (please correct me if I misunderstand). Reading through the list of entitlements noted here https://developer.apple.com/documentation/bundleresources/entitlements, the relevant entitlements that an executable (like "java") which internally invokes BSD socket related syscalls and library functions, appear to be: com.apple.security.network.client - https://developer.apple.com/documentation/bundleresources/entitlements/com.apple.security.network.client com.apple.security.network.server - https://developer.apple.com/documentation/bundleresources/entitlements/com.apple.security.network.server com.apple.developer.networking.multicast - https://developer.apple.com/documentation/bundleresources/entitlements/com.apple.developer.networking.multicast Is my understanding correct that these are the relevant ones for MacOS? Are there any more entitlements that are of interest? Would it then mean that the executables (java for example) would have to enroll for these entitlements to be allowed to invoke those functions at runtime? Reading through https://developer.apple.com/documentation/bundleresources/entitlements, I believe that even when an executable is configured with these entitlements, when the application is running if that executable makes use of any operations for which it has an entitlement, the user is still prompted (through a UI notification) whether or not to allow the operation. Did I understand it right? The part that isn't clear from that documentation is, if the executable hasn't been configured with a relevant entitlement, what happens when the executable invokes on such operation. Will the user see a UI notification asking permission to allow the operation (just like if an entitlement was configured)? Or does that operation just fail in some behind the scenes way? Coming back to the networking specific entitlements, I found a couple of places in the MacOS documentation where it is claimed that the com.apple.developer.networking.multicast entitlement is only applicable on iOS. In fact, the entitlement definition page for it https://developer.apple.com/documentation/bundleresources/entitlements/com.apple.developer.networking.multicast says: "Your app must have this entitlement to send or receive IP multicast or broadcast on iOS. It also allows your app to browse and advertise arbitrary Bonjour service types." Yet, that same page, a few lines above, shows "macOS 10.0+". So, is com.apple.developer.networking.multicast entitlement necessary for an executable running on MacOS which deals with multicasting using BSD sockets? As a more general comment about the documentation, I see that the main entitlements page here https://developer.apple.com/documentation/bundleresources/entitlements categorizes some of these entitlements under specific categories, for example, notice how some entitlements are categorized under "App Clips". I think it would be useful if there was a category for "BSD sockets" and under that it would list all relevant entitlements that are applicable, even if it means repeating the entitlement names across different categories. I think that will make it easier to identify the relevant entitlements. Finally, more as a long term question, how does one watch or keep track of these required entitlements for these operations. What I mean is, is it expected that application developers keep visiting the macos documentation, like these pages, to know that a new entitlement is now required in a new macos (update) release? Or are there other ways to keep track of it? For example, if a newer macos requires a new entitlement, then when (an already built) executable is run on that version of macos, perhaps generate a notification or some kind of explicit error which makes it clear what entitlement is missing? I have read through https://developer.apple.com/documentation/bundleresources/diagnosing-issues-with-entitlements but that page focuses on identifying such issues when a executable is being built and doesn't explain the case where an executable has already been shipped with X entitlements and a new Y entitlement is now required to run on a newer version of macos.